/*
 * Copyright 2010 Google Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.dev.jjs.impl;

import com.google.gwt.dev.javac.JSORestrictionsChecker;
import com.google.gwt.dev.javac.JsniMethod;
import com.google.gwt.dev.jdt.SafeASTVisitor;
import com.google.gwt.dev.jjs.InternalCompilerException;
import com.google.gwt.dev.jjs.SourceInfo;
import com.google.gwt.dev.jjs.SourceOrigin;
import com.google.gwt.dev.jjs.ast.AccessModifier;
import com.google.gwt.dev.jjs.ast.JAbsentArrayDimension;
import com.google.gwt.dev.jjs.ast.JArrayLength;
import com.google.gwt.dev.jjs.ast.JArrayRef;
import com.google.gwt.dev.jjs.ast.JArrayType;
import com.google.gwt.dev.jjs.ast.JAssertStatement;
import com.google.gwt.dev.jjs.ast.JBinaryOperation;
import com.google.gwt.dev.jjs.ast.JBinaryOperator;
import com.google.gwt.dev.jjs.ast.JBlock;
import com.google.gwt.dev.jjs.ast.JBooleanLiteral;
import com.google.gwt.dev.jjs.ast.JBreakStatement;
import com.google.gwt.dev.jjs.ast.JCaseStatement;
import com.google.gwt.dev.jjs.ast.JCastOperation;
import com.google.gwt.dev.jjs.ast.JCharLiteral;
import com.google.gwt.dev.jjs.ast.JClassLiteral;
import com.google.gwt.dev.jjs.ast.JClassType;
import com.google.gwt.dev.jjs.ast.JConditional;
import com.google.gwt.dev.jjs.ast.JConstructor;
import com.google.gwt.dev.jjs.ast.JContinueStatement;
import com.google.gwt.dev.jjs.ast.JDeclarationStatement;
import com.google.gwt.dev.jjs.ast.JDeclaredType;
import com.google.gwt.dev.jjs.ast.JDoStatement;
import com.google.gwt.dev.jjs.ast.JDoubleLiteral;
import com.google.gwt.dev.jjs.ast.JEnumField;
import com.google.gwt.dev.jjs.ast.JEnumType;
import com.google.gwt.dev.jjs.ast.JExpression;
import com.google.gwt.dev.jjs.ast.JExpressionStatement;
import com.google.gwt.dev.jjs.ast.JField;
import com.google.gwt.dev.jjs.ast.JField.Disposition;
import com.google.gwt.dev.jjs.ast.JFieldRef;
import com.google.gwt.dev.jjs.ast.JFloatLiteral;
import com.google.gwt.dev.jjs.ast.JForStatement;
import com.google.gwt.dev.jjs.ast.JIfStatement;
import com.google.gwt.dev.jjs.ast.JInstanceOf;
import com.google.gwt.dev.jjs.ast.JIntLiteral;
import com.google.gwt.dev.jjs.ast.JInterfaceType;
import com.google.gwt.dev.jjs.ast.JLabel;
import com.google.gwt.dev.jjs.ast.JLabeledStatement;
import com.google.gwt.dev.jjs.ast.JLiteral;
import com.google.gwt.dev.jjs.ast.JLocal;
import com.google.gwt.dev.jjs.ast.JLocalRef;
import com.google.gwt.dev.jjs.ast.JLongLiteral;
import com.google.gwt.dev.jjs.ast.JMethod;
import com.google.gwt.dev.jjs.ast.JMethodBody;
import com.google.gwt.dev.jjs.ast.JMethodCall;
import com.google.gwt.dev.jjs.ast.JNewArray;
import com.google.gwt.dev.jjs.ast.JNewInstance;
import com.google.gwt.dev.jjs.ast.JNode;
import com.google.gwt.dev.jjs.ast.JNullLiteral;
import com.google.gwt.dev.jjs.ast.JNullType;
import com.google.gwt.dev.jjs.ast.JParameter;
import com.google.gwt.dev.jjs.ast.JParameterRef;
import com.google.gwt.dev.jjs.ast.JPostfixOperation;
import com.google.gwt.dev.jjs.ast.JPrefixOperation;
import com.google.gwt.dev.jjs.ast.JPrimitiveType;
import com.google.gwt.dev.jjs.ast.JProgram;
import com.google.gwt.dev.jjs.ast.JReferenceType;
import com.google.gwt.dev.jjs.ast.JReturnStatement;
import com.google.gwt.dev.jjs.ast.JStatement;
import com.google.gwt.dev.jjs.ast.JStringLiteral;
import com.google.gwt.dev.jjs.ast.JSwitchStatement;
import com.google.gwt.dev.jjs.ast.JThisRef;
import com.google.gwt.dev.jjs.ast.JThrowStatement;
import com.google.gwt.dev.jjs.ast.JTryStatement;
import com.google.gwt.dev.jjs.ast.JType;
import com.google.gwt.dev.jjs.ast.JUnaryOperator;
import com.google.gwt.dev.jjs.ast.JVariable;
import com.google.gwt.dev.jjs.ast.JWhileStatement;
import com.google.gwt.dev.jjs.ast.js.JsniClassLiteral;
import com.google.gwt.dev.jjs.ast.js.JsniFieldRef;
import com.google.gwt.dev.jjs.ast.js.JsniMethodBody;
import com.google.gwt.dev.jjs.ast.js.JsniMethodRef;
import com.google.gwt.dev.js.JsAbstractSymbolResolver;
import com.google.gwt.dev.js.ast.JsContext;
import com.google.gwt.dev.js.ast.JsExpression;
import com.google.gwt.dev.js.ast.JsFunction;
import com.google.gwt.dev.js.ast.JsModVisitor;
import com.google.gwt.dev.js.ast.JsName;
import com.google.gwt.dev.js.ast.JsNameRef;
import com.google.gwt.dev.js.ast.JsNode;
import com.google.gwt.dev.js.ast.JsParameter;
import com.google.gwt.dev.util.StringInterner;

import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.internal.compiler.ast.AND_AND_Expression;
import org.eclipse.jdt.internal.compiler.ast.ASTNode;
import org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration;
import org.eclipse.jdt.internal.compiler.ast.AllocationExpression;
import org.eclipse.jdt.internal.compiler.ast.AnnotationMethodDeclaration;
import org.eclipse.jdt.internal.compiler.ast.Argument;
import org.eclipse.jdt.internal.compiler.ast.ArrayAllocationExpression;
import org.eclipse.jdt.internal.compiler.ast.ArrayInitializer;
import org.eclipse.jdt.internal.compiler.ast.ArrayReference;
import org.eclipse.jdt.internal.compiler.ast.AssertStatement;
import org.eclipse.jdt.internal.compiler.ast.Assignment;
import org.eclipse.jdt.internal.compiler.ast.BinaryExpression;
import org.eclipse.jdt.internal.compiler.ast.Block;
import org.eclipse.jdt.internal.compiler.ast.BreakStatement;
import org.eclipse.jdt.internal.compiler.ast.CaseStatement;
import org.eclipse.jdt.internal.compiler.ast.CastExpression;
import org.eclipse.jdt.internal.compiler.ast.CharLiteral;
import org.eclipse.jdt.internal.compiler.ast.ClassLiteralAccess;
import org.eclipse.jdt.internal.compiler.ast.Clinit;
import org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration;
import org.eclipse.jdt.internal.compiler.ast.CompoundAssignment;
import org.eclipse.jdt.internal.compiler.ast.ConditionalExpression;
import org.eclipse.jdt.internal.compiler.ast.ConstructorDeclaration;
import org.eclipse.jdt.internal.compiler.ast.ContinueStatement;
import org.eclipse.jdt.internal.compiler.ast.DoStatement;
import org.eclipse.jdt.internal.compiler.ast.DoubleLiteral;
import org.eclipse.jdt.internal.compiler.ast.EmptyStatement;
import org.eclipse.jdt.internal.compiler.ast.EqualExpression;
import org.eclipse.jdt.internal.compiler.ast.ExplicitConstructorCall;
import org.eclipse.jdt.internal.compiler.ast.Expression;
import org.eclipse.jdt.internal.compiler.ast.ExtendedStringLiteral;
import org.eclipse.jdt.internal.compiler.ast.FalseLiteral;
import org.eclipse.jdt.internal.compiler.ast.FieldDeclaration;
import org.eclipse.jdt.internal.compiler.ast.FieldReference;
import org.eclipse.jdt.internal.compiler.ast.FloatLiteral;
import org.eclipse.jdt.internal.compiler.ast.ForStatement;
import org.eclipse.jdt.internal.compiler.ast.ForeachStatement;
import org.eclipse.jdt.internal.compiler.ast.IfStatement;
import org.eclipse.jdt.internal.compiler.ast.Initializer;
import org.eclipse.jdt.internal.compiler.ast.InstanceOfExpression;
import org.eclipse.jdt.internal.compiler.ast.IntLiteral;
import org.eclipse.jdt.internal.compiler.ast.LabeledStatement;
import org.eclipse.jdt.internal.compiler.ast.LocalDeclaration;
import org.eclipse.jdt.internal.compiler.ast.LongLiteral;
import org.eclipse.jdt.internal.compiler.ast.MarkerAnnotation;
import org.eclipse.jdt.internal.compiler.ast.MessageSend;
import org.eclipse.jdt.internal.compiler.ast.MethodDeclaration;
import org.eclipse.jdt.internal.compiler.ast.NameReference;
import org.eclipse.jdt.internal.compiler.ast.NormalAnnotation;
import org.eclipse.jdt.internal.compiler.ast.NullLiteral;
import org.eclipse.jdt.internal.compiler.ast.OR_OR_Expression;
import org.eclipse.jdt.internal.compiler.ast.OperatorIds;
import org.eclipse.jdt.internal.compiler.ast.PostfixExpression;
import org.eclipse.jdt.internal.compiler.ast.PrefixExpression;
import org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression;
import org.eclipse.jdt.internal.compiler.ast.QualifiedNameReference;
import org.eclipse.jdt.internal.compiler.ast.QualifiedSuperReference;
import org.eclipse.jdt.internal.compiler.ast.QualifiedThisReference;
import org.eclipse.jdt.internal.compiler.ast.ReturnStatement;
import org.eclipse.jdt.internal.compiler.ast.SingleMemberAnnotation;
import org.eclipse.jdt.internal.compiler.ast.SingleNameReference;
import org.eclipse.jdt.internal.compiler.ast.Statement;
import org.eclipse.jdt.internal.compiler.ast.StringLiteral;
import org.eclipse.jdt.internal.compiler.ast.StringLiteralConcatenation;
import org.eclipse.jdt.internal.compiler.ast.SuperReference;
import org.eclipse.jdt.internal.compiler.ast.SwitchStatement;
import org.eclipse.jdt.internal.compiler.ast.SynchronizedStatement;
import org.eclipse.jdt.internal.compiler.ast.ThisReference;
import org.eclipse.jdt.internal.compiler.ast.ThrowStatement;
import org.eclipse.jdt.internal.compiler.ast.TrueLiteral;
import org.eclipse.jdt.internal.compiler.ast.TryStatement;
import org.eclipse.jdt.internal.compiler.ast.TypeDeclaration;
import org.eclipse.jdt.internal.compiler.ast.UnaryExpression;
import org.eclipse.jdt.internal.compiler.ast.WhileStatement;
import org.eclipse.jdt.internal.compiler.impl.Constant;
import org.eclipse.jdt.internal.compiler.lookup.BaseTypeBinding;
import org.eclipse.jdt.internal.compiler.lookup.Binding;
import org.eclipse.jdt.internal.compiler.lookup.BlockScope;
import org.eclipse.jdt.internal.compiler.lookup.ClassScope;
import org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope;
import org.eclipse.jdt.internal.compiler.lookup.FieldBinding;
import org.eclipse.jdt.internal.compiler.lookup.LocalTypeBinding;
import org.eclipse.jdt.internal.compiler.lookup.LocalVariableBinding;
import org.eclipse.jdt.internal.compiler.lookup.MethodBinding;
import org.eclipse.jdt.internal.compiler.lookup.MethodScope;
import org.eclipse.jdt.internal.compiler.lookup.NestedTypeBinding;
import org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding;
import org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding;
import org.eclipse.jdt.internal.compiler.lookup.SyntheticArgumentBinding;
import org.eclipse.jdt.internal.compiler.lookup.SyntheticMethodBinding;
import org.eclipse.jdt.internal.compiler.lookup.TypeBinding;
import org.eclipse.jdt.internal.compiler.lookup.TypeIds;
import org.eclipse.jdt.internal.compiler.lookup.VariableBinding;
import org.eclipse.jdt.internal.compiler.util.Util;

import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.IdentityHashMap;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import java.util.Map;
import java.util.Set;
import java.util.Stack;

/**
 * Constructs a GWT Java AST from a single isolated compilation unit. The AST is
 * not associated with any {@link com.google.gwt.dev.jjs.ast.JProgram} and will
 * contain unresolved references.
 */
public class GwtAstBuilder {

  /**
   * Visit the JDT AST and produce our own AST. By the end of this pass, the
   * produced AST should contain every piece of information we'll ever need
   * about the code. The JDT nodes should never again be referenced after this.
   * 
   * NOTE ON JDT FORCED OPTIMIZATIONS - If JDT statically determines that a
   * section of code in unreachable, it won't fully resolve that section of
   * code. This invalid-state code causes us major problems. As a result, we
   * have to optimize out those dead blocks early and never try to translate
   * them to our AST.
   */
  class AstVisitor extends SafeASTVisitor {

    /**
     * Resolves local references to function parameters, and JSNI references.
     */
    private class JsniResolver extends JsModVisitor {
      private final GenerateJavaScriptLiterals generator = new GenerateJavaScriptLiterals();
      private final JsniMethodBody nativeMethodBody;

      private JsniResolver(JsniMethodBody nativeMethodBody) {
        this.nativeMethodBody = nativeMethodBody;
      }

      @Override
      public void endVisit(JsNameRef x, JsContext ctx) {
        String ident = x.getIdent();
        if (ident.charAt(0) == '@') {
          Binding binding = jsniRefs.get(ident);
          SourceInfo info = x.getSourceInfo();
          if (binding == null) {
            assert ident.startsWith("@null::");
            if ("@null::nullMethod()".equals(ident)) {
              processMethod(x, info, JMethod.NULL_METHOD);
            } else {
              assert "@null::nullField".equals(ident);
              processField(x, info, JField.NULL_FIELD, ctx);
            }
          } else if (binding instanceof TypeBinding) {
            JType type = typeMap.get((TypeBinding) binding);
            processClassLiteral(x, info, type, ctx);
          } else if (binding instanceof FieldBinding) {
            FieldBinding fieldBinding = (FieldBinding) binding;
            /*
             * We must replace any compile-time constants with the constant
             * value of the field.
             */
            if (isCompileTimeConstant(fieldBinding)) {
              assert !ctx.isLvalue();
              JExpression constant = getConstant(info, fieldBinding.constant());
              generator.accept(constant);
              JsExpression result = generator.pop();
              assert (result != null);
              ctx.replaceMe(result);
            } else {
              // Normal: create a jsniRef.
              JField field = typeMap.get(fieldBinding);
              processField(x, info, field, ctx);
            }
          } else {
            JMethod method = typeMap.get((MethodBinding) binding);
            processMethod(x, info, method);
          }
        }
      }

      private void processClassLiteral(JsNameRef nameRef, SourceInfo info, JType type, JsContext ctx) {
        assert !ctx.isLvalue();
        JsniClassLiteral classLiteral = new JsniClassLiteral(info, nameRef.getIdent(), type);
        nativeMethodBody.addClassRef(classLiteral);
      }

      private void processField(JsNameRef nameRef, SourceInfo info, JField field, JsContext ctx) {
        JsniFieldRef fieldRef =
            new JsniFieldRef(info, nameRef.getIdent(), field, curClass.type, ctx.isLvalue());
        nativeMethodBody.addJsniRef(fieldRef);
      }

      private void processMethod(JsNameRef nameRef, SourceInfo info, JMethod method) {
        JsniMethodRef methodRef =
            new JsniMethodRef(info, nameRef.getIdent(), method, javaLangObject);
        nativeMethodBody.addJsniRef(methodRef);
      }
    }

    /**
     * Resolves the scope of JS identifiers solely within the scope of a method.
     */
    private class JsParameterResolver extends JsAbstractSymbolResolver {
      private final JsFunction jsFunction;

      public JsParameterResolver(JsFunction jsFunction) {
        this.jsFunction = jsFunction;
      }

      @Override
      public void resolve(JsNameRef x) {
        // Only resolve unqualified names
        if (x.getQualifier() == null) {
          JsName name = getScope().findExistingName(x.getIdent());

          // Ensure that we're resolving a name from the function's parameters
          JsNode node = name == null ? null : name.getStaticRef();
          if (node instanceof JsParameter) {
            JsParameter param = (JsParameter) node;
            if (jsFunction.getParameters().contains(param)) {
              x.resolve(name);
            }
          }
        }
      }
    }

    private final Stack<ClassInfo> classStack = new Stack<ClassInfo>();

    private ClassInfo curClass = null;

    private MethodInfo curMethod = null;

    private final Stack<MethodInfo> methodStack = new Stack<MethodInfo>();

    private final ArrayList<JNode> nodeStack = new ArrayList<JNode>();

    @Override
    public void endVisit(AllocationExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        List<JExpression> arguments = popCallArgs(info, x.arguments, x.binding);
        pushNewExpression(info, x, null, arguments, scope);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(AND_AND_Expression x, BlockScope scope) {
      pushBinaryOp(x, JBinaryOperator.AND);
    }

    @Override
    public void endVisit(AnnotationMethodDeclaration x, ClassScope classScope) {
      endVisit((MethodDeclaration) x, classScope);
    }

    @Override
    public void endVisit(ArrayAllocationExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JArrayType type = (JArrayType) typeMap.get(x.resolvedType);

        if (x.initializer != null) {
          // handled by ArrayInitializer.
        } else {
          // Annoyingly, JDT only visits non-null dims, so we can't popList().
          List<JExpression> dims = new ArrayList<JExpression>();
          for (int i = x.dimensions.length - 1; i >= 0; --i) {
            JExpression dimension = pop(x.dimensions[i]);
            // can be null if index expression was empty
            if (dimension == null) {
              dimension = JAbsentArrayDimension.INSTANCE;
            }
            dims.add(dimension);
          }
          // Undo the stack reversal.
          Collections.reverse(dims);
          push(JNewArray.createDims(info, type, dims));
        }
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ArrayInitializer x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JArrayType type = (JArrayType) typeMap.get(x.resolvedType);
        List<JExpression> expressions = pop(x.expressions);
        push(JNewArray.createInitializers(info, type, expressions));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ArrayReference x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JExpression position = pop(x.position);
        JExpression receiver = pop(x.receiver);
        push(new JArrayRef(info, receiver, position));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(AssertStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JExpression exceptionArgument = pop(x.exceptionArgument);
        JExpression assertExpression = pop(x.assertExpression);
        push(new JAssertStatement(info, assertExpression, exceptionArgument));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(Assignment x, BlockScope scope) {
      pushBinaryOp(x, JBinaryOperator.ASG);
    }

    @Override
    public void endVisit(BinaryExpression x, BlockScope scope) {
      JBinaryOperator op;
      int binOp = (x.bits & ASTNode.OperatorMASK) >> ASTNode.OperatorSHIFT;
      switch (binOp) {
        case OperatorIds.LEFT_SHIFT:
          op = JBinaryOperator.SHL;
          break;
        case OperatorIds.RIGHT_SHIFT:
          op = JBinaryOperator.SHR;
          break;
        case OperatorIds.UNSIGNED_RIGHT_SHIFT:
          op = JBinaryOperator.SHRU;
          break;
        case OperatorIds.PLUS:
          if (javaLangString == typeMap.get(x.resolvedType)) {
            op = JBinaryOperator.CONCAT;
          } else {
            op = JBinaryOperator.ADD;
          }
          break;
        case OperatorIds.MINUS:
          op = JBinaryOperator.SUB;
          break;
        case OperatorIds.REMAINDER:
          op = JBinaryOperator.MOD;
          break;
        case OperatorIds.XOR:
          op = JBinaryOperator.BIT_XOR;
          break;
        case OperatorIds.AND:
          op = JBinaryOperator.BIT_AND;
          break;
        case OperatorIds.MULTIPLY:
          op = JBinaryOperator.MUL;
          break;
        case OperatorIds.OR:
          op = JBinaryOperator.BIT_OR;
          break;
        case OperatorIds.DIVIDE:
          op = JBinaryOperator.DIV;
          break;
        case OperatorIds.LESS_EQUAL:
          op = JBinaryOperator.LTE;
          break;
        case OperatorIds.GREATER_EQUAL:
          op = JBinaryOperator.GTE;
          break;
        case OperatorIds.GREATER:
          op = JBinaryOperator.GT;
          break;
        case OperatorIds.LESS:
          op = JBinaryOperator.LT;
          break;
        default:
          throw translateException(x, new InternalCompilerException(
              "Unexpected operator for BinaryExpression"));
      }
      pushBinaryOp(x, op);
    }

    @Override
    public void endVisit(Block x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JBlock block = popBlock(info, x.statements);
        push(block);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(BreakStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        push(new JBreakStatement(info, getOrCreateLabel(info, x.label)));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(CaseStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JExpression constantExpression = pop(x.constantExpression);
        JLiteral caseLiteral;
        if (constantExpression == null) {
          caseLiteral = null;
        } else if (constantExpression instanceof JLiteral) {
          caseLiteral = (JLiteral) constantExpression;
        } else {
          // Adapted from CaseStatement.resolveCase().
          assert x.constantExpression.resolvedType.isEnum();
          NameReference reference = (NameReference) x.constantExpression;
          FieldBinding field = reference.fieldBinding();
          caseLiteral = JIntLiteral.get(field.original().id);
        }
        push(new JCaseStatement(info, caseLiteral));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(CastExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JType type = typeMap.get(x.resolvedType);
        JExpression expression = pop(x.expression);
        if (x.type instanceof NameReference) {
          pop(x.type);
        }
        push(new JCastOperation(info, type, expression));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(CharLiteral x, BlockScope scope) {
      try {
        push(JCharLiteral.get(x.constant.charValue()));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ClassLiteralAccess x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JType type = typeMap.get(x.targetType);
        push(new JClassLiteral(info, type));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(CompoundAssignment x, BlockScope scope) {
      JBinaryOperator op;
      switch (x.operator) {
        case OperatorIds.PLUS:
          if (javaLangString == typeMap.get(x.resolvedType)) {
            op = JBinaryOperator.ASG_CONCAT;
          } else {
            op = JBinaryOperator.ASG_ADD;
          }
          break;
        case OperatorIds.MINUS:
          op = JBinaryOperator.ASG_SUB;
          break;
        case OperatorIds.MULTIPLY:
          op = JBinaryOperator.ASG_MUL;
          break;
        case OperatorIds.DIVIDE:
          op = JBinaryOperator.ASG_DIV;
          break;
        case OperatorIds.AND:
          op = JBinaryOperator.ASG_BIT_AND;
          break;
        case OperatorIds.OR:
          op = JBinaryOperator.ASG_BIT_OR;
          break;
        case OperatorIds.XOR:
          op = JBinaryOperator.ASG_BIT_XOR;
          break;
        case OperatorIds.REMAINDER:
          op = JBinaryOperator.ASG_MOD;
          break;
        case OperatorIds.LEFT_SHIFT:
          op = JBinaryOperator.ASG_SHL;
          break;
        case OperatorIds.RIGHT_SHIFT:
          op = JBinaryOperator.ASG_SHR;
          break;
        case OperatorIds.UNSIGNED_RIGHT_SHIFT:
          op = JBinaryOperator.ASG_SHRU;
          break;
        default:
          throw translateException(x, new InternalCompilerException(
              "Unexpected operator for CompoundAssignment"));
      }
      pushBinaryOp(x, op);
    }

    @Override
    public void endVisit(ConditionalExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JType type = typeMap.get(x.resolvedType);
        JExpression valueIfFalse = pop(x.valueIfFalse);
        JExpression valueIfTrue = pop(x.valueIfTrue);
        JExpression condition = pop(x.condition);
        push(new JConditional(info, type, condition, valueIfTrue, valueIfFalse));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ConstructorDeclaration x, ClassScope scope) {
      try {
        List<JStatement> statements = pop(x.statements);
        JStatement constructorCall = pop(x.constructorCall);
        JBlock block = curMethod.body.getBlock();
        SourceInfo info = curMethod.method.getSourceInfo();

        /*
         * Determine if we have an explicit this call. The presence of an
         * explicit this call indicates we can skip certain initialization steps
         * (as the callee will perform those steps for us). These skippable
         * steps are 1) assigning synthetic args to fields and 2) running
         * initializers.
         */
        boolean hasExplicitThis = (x.constructorCall != null) && !x.constructorCall.isSuperAccess();

        /*
         * All synthetic fields must be assigned, unless we have an explicit
         * this constructor call, in which case the callee will assign them for
         * us.
         */
        if (!hasExplicitThis) {
          ReferenceBinding declaringClass = (ReferenceBinding) x.binding.declaringClass.erasure();
          if (isNested(declaringClass)) {
            NestedTypeBinding nestedBinding = (NestedTypeBinding) declaringClass;
            if (nestedBinding.enclosingInstances != null) {
              for (SyntheticArgumentBinding arg : nestedBinding.enclosingInstances) {
                JBinaryOperation asg = assignSyntheticField(info, arg);
                block.addStmt(asg.makeStatement());
              }
            }

            if (nestedBinding.outerLocalVariables != null) {
              for (SyntheticArgumentBinding arg : nestedBinding.outerLocalVariables) {
                JBinaryOperation asg = assignSyntheticField(info, arg);
                block.addStmt(asg.makeStatement());
              }
            }
          }
        }

        if (constructorCall != null) {
          block.addStmt(constructorCall);
        }

        /*
         * Call the synthetic instance initializer method, unless we have an
         * explicit this constructor call, in which case the callee will.
         */
        if (!hasExplicitThis) {
          JMethod initMethod = curClass.type.getInitMethod();
          JMethodCall initCall = new JMethodCall(info, makeThisRef(info), initMethod);
          block.addStmt(initCall.makeStatement());
        }

        // user code (finally!)
        block.addStmts(statements);
        popMethodInfo();
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ContinueStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        push(new JContinueStatement(info, getOrCreateLabel(info, x.label)));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(DoStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JExpression condition = pop(x.condition);
        JStatement action = pop(x.action);
        push(new JDoStatement(info, condition, action));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(DoubleLiteral x, BlockScope scope) {
      try {
        push(JDoubleLiteral.get(x.constant.doubleValue()));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(EmptyStatement x, BlockScope scope) {
      push(null);
    }

    @Override
    public void endVisit(EqualExpression x, BlockScope scope) {
      JBinaryOperator op;
      switch ((x.bits & ASTNode.OperatorMASK) >> ASTNode.OperatorSHIFT) {
        case OperatorIds.EQUAL_EQUAL:
          op = JBinaryOperator.EQ;
          break;
        case OperatorIds.NOT_EQUAL:
          op = JBinaryOperator.NEQ;
          break;
        default:
          throw translateException(x, new InternalCompilerException(
              "Unexpected operator for EqualExpression"));
      }
      pushBinaryOp(x, op);
    }

    @Override
    public void endVisit(ExplicitConstructorCall x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JConstructor ctor = (JConstructor) typeMap.get(x.binding);
        JExpression trueQualifier = makeThisRef(info);
        JMethodCall call = new JMethodCall(info, trueQualifier, ctor);
        List<JExpression> callArgs = popCallArgs(info, x.arguments, x.binding);

        if (curClass.classType.isEnumOrSubclass() != null) {
          // Enums: wire up synthetic name/ordinal params to the super method.
          JParameterRef enumNameRef = new JParameterRef(info, curMethod.method.getParams().get(0));
          call.addArg(enumNameRef);
          JParameterRef enumOrdinalRef =
              new JParameterRef(info, curMethod.method.getParams().get(1));
          call.addArg(enumOrdinalRef);
        }

        if (x.isSuperAccess()) {
          JExpression qualifier = pop(x.qualification);
          ReferenceBinding superClass = x.binding.declaringClass;
          boolean nestedSuper = isNested(superClass);
          if (nestedSuper) {
            processSuperCallThisArgs(superClass, call, qualifier, x.qualification);
          }
          call.addArgs(callArgs);
          if (nestedSuper) {
            processSuperCallLocalArgs(superClass, call);
          }
        } else {
          assert (x.qualification == null);
          ReferenceBinding declaringClass = x.binding.declaringClass;
          boolean nested = isNested(declaringClass);
          if (nested) {
            processThisCallThisArgs(declaringClass, call);
          }
          call.addArgs(callArgs);
          if (nested) {
            processThisCallLocalArgs(declaringClass, call);
          }
        }
        call.setStaticDispatchOnly();
        push(call.makeStatement());
      } catch (Throwable e) {
        throw translateException(x, e);
      } finally {
        scope.methodScope().isConstructorCall = false;
      }
    }

    @Override
    public void endVisit(ExtendedStringLiteral x, BlockScope scope) {
      endVisit((StringLiteral) x, scope);
    }

    @Override
    public void endVisit(FalseLiteral x, BlockScope scope) {
      push(JBooleanLiteral.FALSE);
    }

    @Override
    public void endVisit(FieldDeclaration x, MethodScope scope) {
      try {
        JExpression initialization = pop(x.initialization);
        JField field = typeMap.get(x.binding);
        if (field instanceof JEnumField) {
          // An enum field must be initialized!
          assert (initialization instanceof JNewInstance);
        }

        if (initialization != null) {
          SourceInfo info = makeSourceInfo(x);
          JExpression instance = null;
          if (!x.isStatic()) {
            instance = makeThisRef(info);
          }
          // JDeclarationStatement's ctor sets up the field's initializer.
          JStatement decl =
              new JDeclarationStatement(info, new JFieldRef(info, instance, field, curClass.type),
                  initialization);
          // will either be init or clinit
          curMethod.body.getBlock().addStmt(decl);
        }
        popMethodInfo();
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(FieldReference x, BlockScope scope) {
      try {
        FieldBinding fieldBinding = x.binding;
        SourceInfo info = makeSourceInfo(x);
        JExpression instance = pop(x.receiver);
        JExpression expr;
        if (fieldBinding.declaringClass == null) {
          if (!ARRAY_LENGTH_FIELD.equals(String.valueOf(fieldBinding.name))) {
            throw new InternalCompilerException("Expected [array].length.");
          }
          expr = new JArrayLength(info, instance);
        } else {
          JField field = typeMap.get(fieldBinding);
          expr = new JFieldRef(info, instance, field, curClass.type);
        }

        if (x.genericCast != null) {
          JType castType = typeMap.get(x.genericCast);
          /*
           * Note, this may result in an invalid AST due to an LHS cast
           * operation. We fix this up in FixAssignmentToUnbox.
           */
          expr = maybeCast(castType, expr);
        }
        push(expr);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(FloatLiteral x, BlockScope scope) {
      try {
        push(JFloatLiteral.get(x.constant.floatValue()));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ForeachStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);

        JBlock body = popBlock(info, x.action);
        JExpression collection = pop(x.collection);
        JDeclarationStatement elementDecl = pop(x.elementVariable);
        assert (elementDecl.initializer == null);

        JLocal elementVar = (JLocal) curMethod.locals.get(x.elementVariable.binding);
        String elementVarName = elementVar.getName();

        JForStatement result;
        if (x.collectionVariable != null) {
          /**
           * <pre>
         * for (final T[] i$array = collection,
         *          int i$index = 0,
         *          final int i$max = i$array.length;
         *      i$index < i$max; ++i$index) {
         *   T elementVar = i$array[i$index];
         *   // user action
         * }
         * </pre>
           */
          JLocal arrayVar =
              JProgram.createLocal(info, elementVarName + "$array", collection.getType(), true,
                  curMethod.body);
          JLocal indexVar =
              JProgram.createLocal(info, elementVarName + "$index", JPrimitiveType.INT, false,
                  curMethod.body);
          JLocal maxVar =
              JProgram.createLocal(info, elementVarName + "$max", JPrimitiveType.INT, true,
                  curMethod.body);

          List<JStatement> initializers = new ArrayList<JStatement>(3);
          // T[] i$array = arr
          initializers.add(makeDeclaration(info, arrayVar, collection));
          // int i$index = 0
          initializers.add(makeDeclaration(info, indexVar, JIntLiteral.get(0)));
          // int i$max = i$array.length
          initializers.add(makeDeclaration(info, maxVar, new JArrayLength(info, new JLocalRef(info,
              arrayVar))));

          // i$index < i$max
          JExpression condition =
              new JBinaryOperation(info, JPrimitiveType.BOOLEAN, JBinaryOperator.LT, new JLocalRef(
                  info, indexVar), new JLocalRef(info, maxVar));

          // ++i$index
          List<JExpressionStatement> increments = new ArrayList<JExpressionStatement>(1);
          increments.add(new JPrefixOperation(info, JUnaryOperator.INC, new JLocalRef(info,
              indexVar)).makeStatement());

          // T elementVar = i$array[i$index];
          elementDecl.initializer =
              new JArrayRef(info, new JLocalRef(info, arrayVar), new JLocalRef(info, indexVar));
          body.addStmt(0, elementDecl);

          result = new JForStatement(info, initializers, condition, increments, body);
        } else {
          /**
           * <pre>
           * for (Iterator&lt;T&gt; i$iterator = collection.iterator(); i$iterator.hasNext();) {
           *   T elementVar = i$iterator.next();
           *   // user action
           * }
           * </pre>
           */
          CompilationUnitScope cudScope = scope.compilationUnitScope();
          ReferenceBinding javaUtilIterator = scope.getJavaUtilIterator();
          ReferenceBinding javaLangIterable = scope.getJavaLangIterable();
          MethodBinding iterator = javaLangIterable.getExactMethod(ITERATOR, NO_TYPES, cudScope);
          MethodBinding hasNext = javaUtilIterator.getExactMethod(HAS_NEXT, NO_TYPES, cudScope);
          MethodBinding next = javaUtilIterator.getExactMethod(NEXT, NO_TYPES, cudScope);
          JLocal iteratorVar =
              JProgram.createLocal(info, (elementVarName + "$iterator"), typeMap
                  .get(javaUtilIterator), false, curMethod.body);

          List<JStatement> initializers = new ArrayList<JStatement>(1);
          // Iterator<T> i$iterator = collection.iterator()
          initializers.add(makeDeclaration(info, iteratorVar, new JMethodCall(info, collection,
              typeMap.get(iterator))));

          // i$iterator.hasNext()
          JExpression condition =
              new JMethodCall(info, new JLocalRef(info, iteratorVar), typeMap.get(hasNext));

          // T elementVar = (T) i$iterator.next();
          elementDecl.initializer =
              new JMethodCall(info, new JLocalRef(info, iteratorVar), typeMap.get(next));

          // Perform any implicit reference type casts (due to generics).
          // Note this occurs before potential unboxing.
          if (elementVar.getType() != javaLangObject) {
            TypeBinding collectionElementType = (TypeBinding) collectionElementTypeField.get(x);
            JType toType = typeMap.get(collectionElementType);
            assert (toType instanceof JReferenceType);
            elementDecl.initializer = maybeCast(toType, elementDecl.initializer);
          }

          body.addStmt(0, elementDecl);

          result =
              new JForStatement(info, initializers, condition, Collections
                  .<JExpressionStatement> emptyList(), body);
        }

        // May need to box or unbox the element assignment.
        elementDecl.initializer =
            maybeBoxOrUnbox(elementDecl.initializer, x.elementVariableImplicitWidening);
        push(result);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ForStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JStatement action = pop(x.action);
        List<JExpressionStatement> increments = pop(x.increments);
        JExpression condition = pop(x.condition);
        List<JStatement> initializations = pop(x.initializations);
        push(new JForStatement(info, initializations, condition, increments, action));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(IfStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JStatement elseStatement = pop(x.elseStatement);
        JStatement thenStatement = pop(x.thenStatement);
        JExpression condition = pop(x.condition);
        push(new JIfStatement(info, condition, thenStatement, elseStatement));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(Initializer x, MethodScope scope) {
      try {
        JBlock block = pop(x.block);
        if (block != null) {
          curMethod.body.getBlock().addStmt(block);
        }
        popMethodInfo();
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(InstanceOfExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JExpression expr = pop(x.expression);
        JReferenceType testType = (JReferenceType) typeMap.get(x.type.resolvedType);
        push(new JInstanceOf(info, testType, expr));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(IntLiteral x, BlockScope scope) {
      try {
        push(JIntLiteral.get(x.constant.intValue()));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(LabeledStatement x, BlockScope scope) {
      try {
        JStatement statement = pop(x.statement);
        if (statement == null) {
          push(null);
          return;
        }
        SourceInfo info = makeSourceInfo(x);
        push(new JLabeledStatement(info, getOrCreateLabel(info, x.label), statement));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(LocalDeclaration x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JLocal local = (JLocal) curMethod.locals.get(x.binding);
        assert local != null;
        JLocalRef localRef = new JLocalRef(info, local);
        JExpression initialization = pop(x.initialization);
        push(new JDeclarationStatement(info, localRef, initialization));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(LongLiteral x, BlockScope scope) {
      try {
        push(JLongLiteral.get(x.constant.longValue()));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(MessageSend x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JMethod method = typeMap.get(x.binding);

        List<JExpression> arguments = popCallArgs(info, x.arguments, x.binding);
        JExpression receiver = pop(x.receiver);
        if (x.receiver instanceof ThisReference) {
          if (method.isStatic()) {
            // don't bother qualifying it, it's a no-op
            receiver = null;
          } else if ((x.bits & ASTNode.DepthMASK) != 0) {
            // outer method can be reached through emulation if implicit access
            ReferenceBinding targetType =
                scope.enclosingSourceType().enclosingTypeAt(
                    (x.bits & ASTNode.DepthMASK) >> ASTNode.DepthSHIFT);
            receiver = makeThisReference(info, targetType, true, scope);
          } else if (x.receiver.sourceStart == 0) {
            // Synthetic this ref with bad source info; fix the info.
            JThisRef oldRef = (JThisRef) receiver;
            receiver = new JThisRef(info, oldRef.getClassType());
          }
        }

        JMethodCall call = new JMethodCall(info, receiver, method);

        // On a super ref, don't allow polymorphic dispatch. Oddly enough,
        // QualifiedSuperReference not derived from SuperReference!
        boolean isSuperRef =
            x.receiver instanceof SuperReference || x.receiver instanceof QualifiedSuperReference;
        if (isSuperRef) {
          call.setStaticDispatchOnly();
        }

        // The arguments come first...
        call.addArgs(arguments);

        if (x.valueCast != null) {
          JType castType = typeMap.get(x.valueCast);
          push(maybeCast(castType, call));
        } else {
          push(call);
        }
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(MethodDeclaration x, ClassScope scope) {
      try {
        if (x.isNative()) {
          processNativeMethod(x);
        } else {
          List<JStatement> statements = pop(x.statements);
          curMethod.body.getBlock().addStmts(statements);
        }
        popMethodInfo();
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(NullLiteral x, BlockScope scope) {
      push(JNullLiteral.INSTANCE);
    }

    @Override
    public void endVisit(OR_OR_Expression x, BlockScope scope) {
      pushBinaryOp(x, JBinaryOperator.OR);
    }

    @Override
    public void endVisit(PostfixExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JUnaryOperator op;
        switch (x.operator) {
          case OperatorIds.MINUS:
            op = JUnaryOperator.DEC;
            break;

          case OperatorIds.PLUS:
            op = JUnaryOperator.INC;
            break;

          default:
            throw new InternalCompilerException("Unexpected postfix operator");
        }

        JExpression lhs = pop(x.lhs);
        push(new JPostfixOperation(info, op, lhs));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(PrefixExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JUnaryOperator op;
        switch (x.operator) {
          case OperatorIds.MINUS:
            op = JUnaryOperator.DEC;
            break;

          case OperatorIds.PLUS:
            op = JUnaryOperator.INC;
            break;

          default:
            throw new InternalCompilerException("Unexpected prefix operator");
        }

        JExpression lhs = pop(x.lhs);
        push(new JPrefixOperation(info, op, lhs));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(QualifiedAllocationExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        List<JExpression> arguments = popCallArgs(info, x.arguments, x.binding);
        pushNewExpression(info, x, x.enclosingInstance(), arguments, scope);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(QualifiedNameReference x, BlockScope scope) {
      try {
        JExpression curRef = resolveNameReference(x, scope);
        if (curRef == null) {
          push(null);
          return;
        }
        if (x.genericCast != null) {
          JType castType = typeMap.get(x.genericCast);
          curRef = maybeCast(castType, curRef);
        }
        SourceInfo info = curRef.getSourceInfo();

        /*
         * JDT represents multiple field access as an array of fields, each
         * qualified by everything to the left. So each subsequent item in
         * otherBindings takes the current expression as a qualifier.
         */
        if (x.otherBindings != null) {
          for (int i = 0; i < x.otherBindings.length; ++i) {
            FieldBinding fieldBinding = x.otherBindings[i];
            if (fieldBinding.declaringClass == null) {
              // probably array.length
              if (!ARRAY_LENGTH_FIELD.equals(String.valueOf(fieldBinding.name))) {
                throw new InternalCompilerException("Expected [array].length.");
              }
              curRef = new JArrayLength(info, curRef);
            } else {
              JField field = typeMap.get(fieldBinding);
              curRef = new JFieldRef(info, curRef, field, curClass.type);
            }
            if (x.otherGenericCasts != null && x.otherGenericCasts[i] != null) {
              JType castType = typeMap.get(x.otherGenericCasts[i]);
              curRef = maybeCast(castType, curRef);
            }
          }
        }
        push(curRef);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(QualifiedSuperReference x, BlockScope scope) {
      try {
        // Oddly enough, super refs can be modeled as this refs, because
        // whatever expression they qualify has already been resolved.
        endVisit((QualifiedThisReference) x, scope);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(QualifiedThisReference x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        ReferenceBinding targetType = (ReferenceBinding) x.qualification.resolvedType;
        push(makeThisReference(info, targetType, true, scope));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ReturnStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JExpression expression = pop(x.expression);
        push(new JReturnStatement(info, expression));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(SingleNameReference x, BlockScope scope) {
      try {
        JExpression result = resolveNameReference(x, scope);
        if (result == null) {
          push(null);
          return;
        }
        if (x.genericCast != null) {
          JType castType = typeMap.get(x.genericCast);
          result = maybeCast(castType, result);
        }
        push(result);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(StringLiteral x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        push(getStringLiteral(info, x.constant.stringValue()));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(StringLiteralConcatenation x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        push(getStringLiteral(info, x.constant.stringValue()));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(SuperReference x, BlockScope scope) {
      try {
        assert (typeMap.get(x.resolvedType) == curClass.classType.getSuperClass());
        // Super refs can be modeled as a this ref.
        push(makeThisRef(makeSourceInfo(x)));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(SwitchStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);

        JBlock block = popBlock(info, x.statements);
        JExpression expression = pop(x.expression);

        if (x.expression.resolvedType.isEnum()) {
          // synthesize a call to ordinal().
          ReferenceBinding javaLangEnum = scope.getJavaLangEnum();
          MethodBinding ordinal = javaLangEnum.getMethods(ORDINAL)[0];
          expression = new JMethodCall(info, expression, typeMap.get(ordinal));
        }
        push(new JSwitchStatement(info, expression, block));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(SynchronizedStatement x, BlockScope scope) {
      try {
        JBlock block = pop(x.block);
        JExpression expression = pop(x.expression);
        block.addStmt(0, expression.makeStatement());
        push(block);
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ThisReference x, BlockScope scope) {
      try {
        assert (typeMap.get(x.resolvedType) == curClass.classType);
        push(makeThisRef(makeSourceInfo(x)));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(ThrowStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JExpression exception = pop(x.exception);
        push(new JThrowStatement(info, exception));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(TrueLiteral x, BlockScope scope) {
      push(JBooleanLiteral.TRUE);
    }

    @Override
    public void endVisit(TryStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);

        JBlock finallyBlock = pop(x.finallyBlock);
        List<JBlock> catchBlocks = pop(x.catchBlocks);
        JBlock tryBlock = pop(x.tryBlock);

        List<JLocalRef> catchArgs = new ArrayList<JLocalRef>();
        if (x.catchBlocks != null) {
          for (Argument argument : x.catchArguments) {
            JLocal local = (JLocal) curMethod.locals.get(argument.binding);
            catchArgs.add(new JLocalRef(info, local));
          }
        }
        push(new JTryStatement(info, tryBlock, catchArgs, catchBlocks, finallyBlock));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(TypeDeclaration x, ClassScope scope) {
      endVisit(x);
    }

    @Override
    public void endVisit(TypeDeclaration x, CompilationUnitScope scope) {
      endVisit(x);
    }

    @Override
    public void endVisit(UnaryExpression x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JUnaryOperator op;
        int operator = ((x.bits & ASTNode.OperatorMASK) >> ASTNode.OperatorSHIFT);

        switch (operator) {
          case OperatorIds.MINUS:
            op = JUnaryOperator.NEG;
            break;

          case OperatorIds.NOT:
            op = JUnaryOperator.NOT;
            break;

          case OperatorIds.PLUS:
            // Odd case.. useless + operator; just leave the operand on the
            // stack.
            return;

          case OperatorIds.TWIDDLE:
            op = JUnaryOperator.BIT_NOT;
            break;

          default:
            throw new InternalCompilerException("Unexpected operator for unary expression");
        }

        JExpression expression = pop(x.expression);
        push(new JPrefixOperation(info, op, expression));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisit(WhileStatement x, BlockScope scope) {
      try {
        SourceInfo info = makeSourceInfo(x);
        JStatement action = pop(x.action);
        JExpression condition = pop(x.condition);
        push(new JWhileStatement(info, condition, action));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public void endVisitValid(TypeDeclaration x, BlockScope scope) {
      endVisit(x);
      if (!x.binding.isAnonymousType()) {
        // Class declaration as a statement; insert a dummy statement.
        push(null);
      }
    }

    public boolean isJavaScriptObject(JClassType type) {
      if (type == null) {
        return false;
      }
      if (JProgram.JAVASCRIPTOBJECT.equals(type.getName())) {
        return true;
      }
      return isJavaScriptObject(type.getSuperClass());
    }

    @Override
    public boolean visit(AnnotationMethodDeclaration x, ClassScope classScope) {
      return visit((MethodDeclaration) x, classScope);
    }

    @Override
    public boolean visit(Argument x, BlockScope scope) {
      // handled by parents
      return true;
    }

    @Override
    public boolean visit(Block x, BlockScope scope) {
      x.statements = reduceToReachable(x.statements);
      return true;
    }

    @Override
    public boolean visit(ConstructorDeclaration x, ClassScope scope) {
      try {
        JConstructor method = (JConstructor) typeMap.get(x.binding);
        assert !method.isExternal();
        JMethodBody body = new JMethodBody(method.getSourceInfo());
        method.setBody(body);
        pushMethodInfo(new MethodInfo(method, body, x.scope));

        // Map all arguments.
        Iterator<JParameter> it = method.getParams().iterator();

        // Enum arguments have no mapping.
        if (curClass.classType.isEnumOrSubclass() != null) {
          // Skip past name and ordinal.
          it.next();
          it.next();
        }

        // Map synthetic arguments for outer this.
        ReferenceBinding declaringClass = (ReferenceBinding) x.binding.declaringClass.erasure();
        boolean isNested = isNested(declaringClass);
        if (isNested) {
          NestedTypeBinding nestedBinding = (NestedTypeBinding) declaringClass;
          if (nestedBinding.enclosingInstances != null) {
            for (int i = 0; i < nestedBinding.enclosingInstances.length; ++i) {
              SyntheticArgumentBinding arg = nestedBinding.enclosingInstances[i];
              curMethod.locals.put(arg, it.next());
            }
          }
        }

        // Map user arguments.
        if (x.arguments != null) {
          for (Argument argument : x.arguments) {
            curMethod.locals.put(argument.binding, it.next());
          }
        }

        // Map synthetic arguments for locals.
        if (isNested) {
          // add synthetic args for locals
          NestedTypeBinding nestedBinding = (NestedTypeBinding) declaringClass;
          // add synthetic args for outer this and locals
          if (nestedBinding.outerLocalVariables != null) {
            for (int i = 0; i < nestedBinding.outerLocalVariables.length; ++i) {
              SyntheticArgumentBinding arg = nestedBinding.outerLocalVariables[i];
              curMethod.locals.put(arg, it.next());
            }
          }
        }

        x.statements = reduceToReachable(x.statements);
        return true;
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public boolean visit(ExplicitConstructorCall explicitConstructor, BlockScope scope) {
      scope.methodScope().isConstructorCall = true;
      return true;
    }

    @Override
    public boolean visit(FieldDeclaration x, MethodScope scope) {
      try {
        assert !typeMap.get(x.binding).isExternal();
        pushInitializerMethodInfo(x, scope);
        return true;
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public boolean visit(ForStatement x, BlockScope scope) {
      // SEE NOTE ON JDT FORCED OPTIMIZATIONS
      if (isOptimizedFalse(x.condition)) {
        x.action = null;
      }
      return true;
    }

    @Override
    public boolean visit(IfStatement x, BlockScope scope) {
      // SEE NOTE ON JDT FORCED OPTIMIZATIONS
      if (isOptimizedFalse(x.condition)) {
        x.thenStatement = null;
      } else if (isOptimizedTrue(x.condition)) {
        x.elseStatement = null;
      }
      return true;
    }

    @Override
    public boolean visit(Initializer x, MethodScope scope) {
      try {
        pushInitializerMethodInfo(x, scope);
        return true;
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public boolean visit(LocalDeclaration x, BlockScope scope) {
      try {
        createLocal(x);
        return true;
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public boolean visit(MarkerAnnotation annotation, BlockScope scope) {
      return false;
    }

    @Override
    public boolean visit(MethodDeclaration x, ClassScope scope) {
      try {
        JMethod method = typeMap.get(x.binding);
        assert !method.isExternal();
        JMethodBody body = null;
        if (!method.isNative()) {
          body = new JMethodBody(method.getSourceInfo());
          method.setBody(body);
        }
        pushMethodInfo(new MethodInfo(method, body, x.scope));

        // Map user arguments.
        Iterator<JParameter> it = method.getParams().iterator();
        if (x.arguments != null) {
          for (Argument argument : x.arguments) {
            curMethod.locals.put(argument.binding, it.next());
          }
        }
        x.statements = reduceToReachable(x.statements);
        return true;
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public boolean visit(NormalAnnotation annotation, BlockScope scope) {
      return false;
    }

    @Override
    public boolean visit(SingleMemberAnnotation annotation, BlockScope scope) {
      return false;
    }

    @Override
    public boolean visit(SwitchStatement x, BlockScope scope) {
      x.statements = reduceToReachable(x.statements);
      return true;
    }

    @Override
    public boolean visit(TryStatement x, BlockScope scope) {
      try {
        if (x.catchBlocks != null) {
          for (Argument argument : x.catchArguments) {
            createLocal(argument);
          }
        }
        return true;
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    @Override
    public boolean visit(TypeDeclaration x, ClassScope scope) {
      return visit(x);
    }

    @Override
    public boolean visit(TypeDeclaration x, CompilationUnitScope scope) {
      return visit(x);
    }

    @Override
    public boolean visit(WhileStatement x, BlockScope scope) {
      // SEE NOTE ON JDT FORCED OPTIMIZATIONS
      if (isOptimizedFalse(x.condition)) {
        x.action = null;
      }
      return true;
    }

    @Override
    public boolean visitValid(TypeDeclaration x, BlockScope scope) {
      // Local types actually need to be created now.
      createTypes(x);
      resolveTypeRefs(x);
      createMembers(x);
      return visit(x);
    }

    protected void endVisit(TypeDeclaration x) {
      JDeclaredType type = curClass.type;
      /*
       * Make clinits chain to super class (JDT doesn't write code to do this).
       * Call super class $clinit;
       */
      if (type.getSuperClass() != null) {
        JMethod myClinit = type.getClinitMethod();
        JMethod superClinit = type.getSuperClass().getClinitMethod();
        JMethodCall superClinitCall = new JMethodCall(myClinit.getSourceInfo(), null, superClinit);
        JMethodBody body = (JMethodBody) myClinit.getBody();
        body.getBlock().addStmt(0, superClinitCall.makeStatement());
      }

      // Implement getClass() implementation for all non-Object classes.
      if (type.getSuperClass() != null && !JSORestrictionsChecker.isJsoSubclass(x.binding)) {
        implementGetClass(type);
      }

      if (type instanceof JEnumType) {
        processEnumType((JEnumType) type);
      }

      if (type instanceof JClassType) {
        addBridgeMethods(x.binding);
      }

      Binding[] rescues = artificialRescues.get(x);
      if (rescues != null) {
        for (Binding rescue : rescues) {
          if (rescue instanceof TypeBinding) {
            type.addArtificialRescue(typeMap.get((TypeBinding) rescue));
          } else if (rescue instanceof FieldBinding) {
            type.addArtificialRescue(typeMap.get((FieldBinding) rescue));
          } else if (rescue instanceof MethodBinding) {
            type.addArtificialRescue(typeMap.get((MethodBinding) rescue));
          } else {
            throw new InternalCompilerException("Unknown artifical rescue binding type.");
          }
        }
      }

      curClass = classStack.pop();
    }

    protected JBlock pop(Block x) {
      return (x == null) ? null : (JBlock) pop();
    }

    protected JExpression pop(Expression x) {
      if (x == null) {
        return null;
      }
      JExpression result = (JExpression) pop();
      if (result == null) {
        assert x instanceof NameReference;
        return null;
      }
      result = simplify(result, x);
      return result;
    }

    @SuppressWarnings("unchecked")
    protected <T extends JExpression> List<T> pop(Expression[] expressions) {
      if (expressions == null) {
        return Collections.emptyList();
      }
      List<T> result = (List<T>) popList(expressions.length);
      for (int i = 0; i < expressions.length; ++i) {
        result.set(i, (T) simplify(result.get(i), expressions[i]));
      }
      return result;
    }

    protected JDeclarationStatement pop(LocalDeclaration decl) {
      return (decl == null) ? null : (JDeclarationStatement) pop();
    }

    protected JStatement pop(Statement x) {
      JNode pop = (x == null) ? null : pop();
      if (x instanceof Expression) {
        return simplify((JExpression) pop, (Expression) x).makeStatement();
      }
      return (JStatement) pop;
    }

    @SuppressWarnings("unchecked")
    protected <T extends JStatement> List<T> pop(Statement[] statements) {
      if (statements == null) {
        return Collections.emptyList();
      }
      List<T> result = (List<T>) popList(statements.length);
      int i = 0;
      for (ListIterator<T> it = result.listIterator(); it.hasNext(); ++i) {
        Object element = it.next();
        if (element == null) {
          it.remove();
        } else if (element instanceof JExpression) {
          it.set((T) simplify((JExpression) element, (Expression) statements[i]).makeStatement());
        }
      }
      return result;
    }

    protected JBlock popBlock(SourceInfo info, Statement statement) {
      JStatement stmt = pop(statement);
      if (stmt instanceof JBlock) {
        return (JBlock) stmt;
      }
      JBlock block = new JBlock(info);
      if (stmt != null) {
        block.addStmt(stmt);
      }
      return block;
    }

    protected JBlock popBlock(SourceInfo info, Statement[] statements) {
      List<JStatement> stmts = pop(statements);
      JBlock block = new JBlock(info);
      block.addStmts(stmts);
      return block;
    }

    protected void pushBinaryOp(Assignment x, JBinaryOperator op) {
      pushBinaryOp(x, op, x.lhs, x.expression);
    }

    protected void pushBinaryOp(BinaryExpression x, JBinaryOperator op) {
      pushBinaryOp(x, op, x.left, x.right);
    }

    protected boolean visit(TypeDeclaration x) {
      JDeclaredType type = (JDeclaredType) typeMap.get(x.binding);
      assert !type.isExternal();
      classStack.push(curClass);
      curClass = new ClassInfo(type, x);

      /*
       * It's okay to defer creation of synthetic fields, they can't be
       * referenced until we analyze the code.
       */
      SourceTypeBinding binding = x.binding;
      if (isNested(binding)) {
        // add synthetic fields for outer this and locals
        assert (type instanceof JClassType);
        NestedTypeBinding nestedBinding = (NestedTypeBinding) binding;
        if (nestedBinding.enclosingInstances != null) {
          for (int i = 0; i < nestedBinding.enclosingInstances.length; ++i) {
            SyntheticArgumentBinding arg = nestedBinding.enclosingInstances[i];
            createSyntheticField(arg, type, Disposition.THIS_REF);
          }
        }

        if (nestedBinding.outerLocalVariables != null) {
          for (int i = 0; i < nestedBinding.outerLocalVariables.length; ++i) {
            SyntheticArgumentBinding arg = nestedBinding.outerLocalVariables[i];
            // See InnerClassTest.testOuterThisFromSuperCall().
            boolean isReallyThisRef = false;
            if (arg.actualOuterLocalVariable instanceof SyntheticArgumentBinding) {
              SyntheticArgumentBinding outer =
                  (SyntheticArgumentBinding) arg.actualOuterLocalVariable;
              if (outer.matchingField != null) {
                JField field = typeMap.get(outer.matchingField);
                if (field.isThisRef()) {
                  isReallyThisRef = true;
                }
              }
            }
            createSyntheticField(arg, type, isReallyThisRef ? Disposition.THIS_REF
                : Disposition.FINAL);
          }
        }
      }
      return true;
    }

    /**
     * <p>
     * Add a bridge method to <code>clazzBinding</code> for any method it
     * inherits that implements an interface method but that has a different
     * erased signature from the interface method.
     * </p>
     * 
     * <p>
     * The need for these bridges was pointed out in issue 3064. The goal is
     * that virtual method calls through an interface type are translated to
     * JavaScript that will function correctly. If the interface signature
     * matches the signature of the implementing method, then nothing special
     * needs to be done. If they are different, due to the use of generics, then
     * GenerateJavaScriptAST is careful to do the right thing. There is a
     * remaining case, though, that GenerateJavaScriptAST is not in a good
     * position to fix: a method could be inherited from a superclass, used to
     * implement an interface method that has a different type signature, and
     * does not have the interface method in its list of overrides. In that
     * case, a bridge method should be added that overrides the interface method
     * and then calls the implementation method.
     * </p>
     * 
     * <p>
     * This method should only be called once all regular, non-bridge methods
     * have been installed on the GWT types.
     * </p>
     */
    private void addBridgeMethods(SourceTypeBinding clazzBinding) {
      /*
       * JDT adds bridge methods in all the places GWT needs them. Use JDT's
       * bridge methods.
       */
      if (clazzBinding.syntheticMethods() != null) {
        for (SyntheticMethodBinding synthmeth : clazzBinding.syntheticMethods()) {
          if (synthmeth.purpose == SyntheticMethodBinding.BridgeMethod && !synthmeth.isStatic()) {
            createBridgeMethod(synthmeth);
          }
        }
      }
    }

    private JBinaryOperation assignSyntheticField(SourceInfo info, SyntheticArgumentBinding arg) {
      JParameter param = (JParameter) curMethod.locals.get(arg);
      assert param != null;
      JField field = curClass.syntheticFields.get(arg);
      assert field != null;
      JFieldRef lhs = makeInstanceFieldRef(info, field);
      JParameterRef rhs = new JParameterRef(info, param);
      JBinaryOperation asg =
          new JBinaryOperation(info, lhs.getType(), JBinaryOperator.ASG, lhs, rhs);
      return asg;
    }

    private JExpression box(JExpression original, int implicitConversion) {
      int typeId = (implicitConversion & TypeIds.IMPLICIT_CONVERSION_MASK) >> 4;
      ClassScope scope = curClass.scope;
      BaseTypeBinding primitiveType = (BaseTypeBinding) TypeBinding.wellKnownType(scope, typeId);
      ReferenceBinding boxType = (ReferenceBinding) scope.boxing(primitiveType);
      MethodBinding valueOfMethod =
          boxType.getExactMethod(VALUE_OF, new TypeBinding[]{primitiveType}, scope
              .compilationUnitScope());
      assert valueOfMethod != null;

      // Add a cast to the correct primitive type if needed.
      JType targetPrimitiveType = typeMap.get(primitiveType);
      if (original.getType() != targetPrimitiveType) {
        original = new JCastOperation(original.getSourceInfo(), targetPrimitiveType, original);
      }

      JMethod boxMethod = typeMap.get(valueOfMethod);
      JMethodCall call = new JMethodCall(original.getSourceInfo(), null, boxMethod);
      call.addArg(original);
      return call;
    }

    /**
     * Create a bridge method. It calls a same-named method with the same
     * arguments, but with a different type signature.
     */
    private void createBridgeMethod(SyntheticMethodBinding jdtBridgeMethod) {
      JMethod implmeth = typeMap.get(jdtBridgeMethod.targetMethod);
      SourceInfo info = implmeth.getSourceInfo();
      JMethod bridgeMethod =
          new JMethod(info, implmeth.getName(), curClass.type, typeMap
              .get(jdtBridgeMethod.returnType), false, false, implmeth.isFinal(), implmeth
              .getAccess());
      typeMap.setMethod(jdtBridgeMethod, bridgeMethod);
      bridgeMethod.setBody(new JMethodBody(info));
      curClass.type.addMethod(bridgeMethod);
      bridgeMethod.setSynthetic();
      int paramIdx = 0;
      List<JParameter> implParams = implmeth.getParams();
      for (TypeBinding jdtParamType : jdtBridgeMethod.parameters) {
        JParameter param = implParams.get(paramIdx++);
        JType paramType = typeMap.get(jdtParamType.erasure());
        JParameter newParam =
            new JParameter(param.getSourceInfo(), param.getName(), paramType, true, false,
                bridgeMethod);
        bridgeMethod.addParam(newParam);
      }
      for (ReferenceBinding exceptionReference : jdtBridgeMethod.thrownExceptions) {
        bridgeMethod.addThrownException((JClassType) typeMap.get(exceptionReference.erasure()));
      }
      bridgeMethod.freezeParamTypes();

      // create a call and pass all arguments through, casting if necessary
      JMethodCall call = new JMethodCall(info, makeThisRef(info), implmeth);
      for (int i = 0; i < bridgeMethod.getParams().size(); i++) {
        JParameter param = bridgeMethod.getParams().get(i);
        JParameterRef paramRef = new JParameterRef(info, param);
        call.addArg(maybeCast(implParams.get(i).getType(), paramRef));
      }

      JMethodBody body = (JMethodBody) bridgeMethod.getBody();
      if (bridgeMethod.getType() == JPrimitiveType.VOID) {
        body.getBlock().addStmt(call.makeStatement());
      } else {
        body.getBlock().addStmt(new JReturnStatement(info, call));
      }
    }

    private JField createEnumValuesField(JEnumType type) {
      // $VALUES = new E[]{A,B,B};
      JArrayType enumArrayType = new JArrayType(type);
      JField valuesField =
          new JField(type.getSourceInfo(), "$VALUES", type, enumArrayType, true, Disposition.FINAL);
      type.addField(valuesField);
      SourceInfo info = type.getSourceInfo();
      List<JExpression> initializers = new ArrayList<JExpression>();
      for (JEnumField field : type.getEnumList()) {
        JFieldRef fieldRef = new JFieldRef(info, null, field, type);
        initializers.add(fieldRef);
      }
      JNewArray newExpr = JNewArray.createInitializers(info, enumArrayType, initializers);
      JFieldRef valuesRef = new JFieldRef(info, null, valuesField, type);
      JDeclarationStatement declStmt = new JDeclarationStatement(info, valuesRef, newExpr);
      JBlock clinitBlock = ((JMethodBody) type.getClinitMethod().getBody()).getBlock();

      /*
       * HACKY: the $VALUES array must be initialized immediately after all of
       * the enum fields, but before any user initialization (which might rely
       * on $VALUES). The "1 + " is the statement containing the call to
       * Enum.$clinit().
       */
      int insertionPoint = 1 + type.getEnumList().size();
      assert clinitBlock.getStatements().size() >= initializers.size() + 1;
      clinitBlock.addStmt(insertionPoint, declStmt);
      return valuesField;
    }

    private JLocal createLocal(LocalDeclaration x) {
      LocalVariableBinding b = x.binding;
      TypeBinding resolvedType = x.type.resolvedType;
      JType localType;
      if (resolvedType.constantPoolName() != null) {
        localType = typeMap.get(resolvedType);
      } else {
        // Special case, a statically unreachable local type.
        localType = JNullType.INSTANCE;
      }
      SourceInfo info = makeSourceInfo(x);
      JLocal newLocal =
          JProgram.createLocal(info, intern(x.name), localType, b.isFinal(), curMethod.body);
      curMethod.locals.put(b, newLocal);
      return newLocal;
    }

    private JField createSyntheticField(SyntheticArgumentBinding arg, JDeclaredType enclosingType,
        Disposition disposition) {
      JType type = typeMap.get(arg.type);
      SourceInfo info = enclosingType.getSourceInfo();
      JField field = new JField(info, intern(arg.name), enclosingType, type, false, disposition);
      enclosingType.addField(field);
      curClass.syntheticFields.put(arg, field);
      if (arg.matchingField != null) {
        typeMap.setField(arg.matchingField, field);
      }
      return field;
    }

    private JExpression getConstant(SourceInfo info, Constant constant) {
      switch (constant.typeID()) {
        case TypeIds.T_int:
          return JIntLiteral.get(constant.intValue());
        case TypeIds.T_byte:
          return JIntLiteral.get(constant.byteValue());
        case TypeIds.T_short:
          return JIntLiteral.get(constant.shortValue());
        case TypeIds.T_char:
          return JCharLiteral.get(constant.charValue());
        case TypeIds.T_float:
          return JFloatLiteral.get(constant.floatValue());
        case TypeIds.T_double:
          return JDoubleLiteral.get(constant.doubleValue());
        case Constant.T_boolean:
          return JBooleanLiteral.get(constant.booleanValue());
        case Constant.T_long:
          return JLongLiteral.get(constant.longValue());
        case Constant.T_JavaLangString:
          return getStringLiteral(info, constant.stringValue());
        case Constant.T_null:
          return JNullLiteral.INSTANCE;
        default:
          throw new InternalCompilerException("Unknown Constant type: " + constant.typeID());
      }
    }

    /**
     * Get a new label of a particular name, or create a new one if it doesn't
     * exist already.
     */
    private JLabel getOrCreateLabel(SourceInfo info, char[] name) {
      if (name == null) {
        return null;
      }
      String sname = intern(name);
      JLabel jlabel = curMethod.labels.get(sname);
      if (jlabel == null) {
        jlabel = new JLabel(info, sname);
        curMethod.labels.put(sname, jlabel);
      }
      return jlabel;
    }

    private JStringLiteral getStringLiteral(SourceInfo info, char[] chars) {
      return new JStringLiteral(info, intern(chars), javaLangString);
    }

    private JStringLiteral getStringLiteral(SourceInfo info, String string) {
      return new JStringLiteral(info, intern(string), javaLangString);
    }

    /**
     * TODO(scottb): move to UnifyAst and only for non-abstract classes.
     */
    private void implementGetClass(JDeclaredType type) {
      JMethod method = type.getMethods().get(2);
      assert ("getClass".equals(method.getName()));
      SourceInfo info = method.getSourceInfo();
      if ("com.google.gwt.lang.Array".equals(type.getName())) {
        /*
         * Don't implement, fall through to Object.getClass(). Array emulation code
         * in com.google.gwt.lang.Array invokes Array.getClass() and expects to get the
         * class literal for the actual runtime type of the array (e.g. Foo[].class) and
         * not Array.class.
         */
        type.getMethods().remove(2);
      } else {
        implementMethod(method, new JClassLiteral(info, type));
      }
    }

    private void implementMethod(JMethod method, JExpression returnValue) {
      JMethodBody body = (JMethodBody) method.getBody();
      JBlock block = body.getBlock();
      SourceInfo info;
      if (block.getStatements().size() > 0) {
        info = block.getStatements().get(0).getSourceInfo();
      } else {
        info = method.getSourceInfo();
      }
      block.clear();
      block.addStmt(new JReturnStatement(info, returnValue));
    }

    private JDeclarationStatement makeDeclaration(SourceInfo info, JLocal local, JExpression value) {
      return new JDeclarationStatement(info, new JLocalRef(info, local), value);
    }

    private JFieldRef makeInstanceFieldRef(SourceInfo info, JField field) {
      return new JFieldRef(info, makeThisRef(info), field, curClass.classType);
    }

    private JExpression makeLocalRef(SourceInfo info, LocalVariableBinding b) {
      JVariable variable = curMethod.locals.get(b);
      assert variable != null;
      if (variable instanceof JLocal) {
        return new JLocalRef(info, (JLocal) variable);
      } else {
        return new JParameterRef(info, (JParameter) variable);
      }
    }

    private JThisRef makeThisRef(SourceInfo info) {
      return new JThisRef(info, curClass.classType);
    }

    private JExpression makeThisReference(SourceInfo info, ReferenceBinding targetType,
        boolean exactMatch, BlockScope scope) {
      targetType = (ReferenceBinding) targetType.erasure();
      Object[] path = scope.getEmulationPath(targetType, exactMatch, false);
      if (path == null) {
        throw new InternalCompilerException("No emulation path.");
      }
      if (path == BlockScope.EmulationPathToImplicitThis) {
        return makeThisRef(info);
      }
      JExpression ref;
      ReferenceBinding type;
      if (curMethod.scope.isInsideInitializer() && path[0] instanceof SyntheticArgumentBinding) {
        SyntheticArgumentBinding b = (SyntheticArgumentBinding) path[0];
        JField field = curClass.syntheticFields.get(b);
        assert field != null;
        ref = makeInstanceFieldRef(info, field);
        type = (ReferenceBinding) b.type.erasure();
      } else if (path[0] instanceof SyntheticArgumentBinding) {
        SyntheticArgumentBinding b = (SyntheticArgumentBinding) path[0];
        JParameter param = (JParameter) curMethod.locals.get(b);
        assert param != null;
        ref = new JParameterRef(info, param);
        type = (ReferenceBinding) b.type.erasure();
      } else if (path[0] instanceof FieldBinding) {
        FieldBinding b = (FieldBinding) path[0];
        JField field = typeMap.get(b);
        assert field != null;
        ref = makeInstanceFieldRef(info, field);
        type = (ReferenceBinding) b.type.erasure();
      } else {
        throw new InternalCompilerException("Unknown emulation path.");
      }
      for (int i = 1; i < path.length; ++i) {
        SyntheticMethodBinding b = (SyntheticMethodBinding) path[i];
        assert type == b.declaringClass.erasure();
        FieldBinding fieldBinding = b.targetReadField;
        JField field = typeMap.get(fieldBinding);
        assert field != null;
        ref = new JFieldRef(info, ref, field, curClass.classType);
        type = (ReferenceBinding) fieldBinding.type.erasure();
      }
      return ref;
    }

    private JExpression maybeBoxOrUnbox(JExpression original, int implicitConversion) {
      if (implicitConversion != -1) {
        if ((implicitConversion & TypeIds.BOXING) != 0) {
          return box(original, implicitConversion);
        } else if ((implicitConversion & TypeIds.UNBOXING) != 0) {
          return unbox(original, implicitConversion);
        }
      }
      return original;
    }

    private JExpression maybeCast(JType expected, JExpression expression) {
      if (expected != expression.getType()) {
        // Must be a generic; insert a cast operation.
        JReferenceType toType = (JReferenceType) expected;
        return new JCastOperation(expression.getSourceInfo(), toType, expression);
      } else {
        return expression;
      }
    }

    private JNode pop() {
      return nodeStack.remove(nodeStack.size() - 1);
    }

    private List<JExpression> popCallArgs(SourceInfo info, Expression[] jdtArgs,
        MethodBinding binding) {
      List<JExpression> args = pop(jdtArgs);
      if (!binding.isVarargs()) {
        return args;
      }

      // Handle the odd var-arg case.
      if (jdtArgs == null) {
        // Get writable collection (args is currently Collections.emptyList()).
        args = new ArrayList<JExpression>(1);
      }

      TypeBinding[] params = binding.parameters;
      int varArg = params.length - 1;

      // See if there's a single varArg which is already an array.
      if (args.size() == params.length) {
        if (jdtArgs[varArg].resolvedType.isCompatibleWith(params[varArg])) {
          // Already the correct array type.
          return args;
        }
      }

      // Need to synthesize an appropriately-typed array.
      List<JExpression> tail = args.subList(varArg, args.size());
      ArrayList<JExpression> initializers = new ArrayList<JExpression>(tail);
      tail.clear();
      JArrayType lastParamType = (JArrayType) typeMap.get(params[varArg]);
      JNewArray newArray = JNewArray.createInitializers(info, lastParamType, initializers);
      args.add(newArray);
      return args;
    }

    private List<? extends JNode> popList(int count) {
      List<JNode> tail = nodeStack.subList(nodeStack.size() - count, nodeStack.size());
      // Make a copy.
      List<JNode> result = new ArrayList<JNode>(tail);
      // Causes the tail to be removed.
      tail.clear();
      return result;
    }

    private void popMethodInfo() {
      curMethod = methodStack.pop();
    }

    private void processEnumType(JEnumType type) {
      JField valuesField = createEnumValuesField(type);

      // $clinit, $init, getClass, valueOf, values
      {
        JMethod valueOfMethod = type.getMethods().get(3);
        assert "valueOf".equals(valueOfMethod.getName());
        writeEnumValueOfMethod(type, valueOfMethod, valuesField);
      }
      {
        JMethod valuesMethod = type.getMethods().get(4);
        assert "values".equals(valuesMethod.getName());
        writeEnumValuesMethod(type, valuesMethod, valuesField);
      }
    }

    private void processNativeMethod(MethodDeclaration x) {
      JMethod method = curMethod.method;
      JsniMethod jsniMethod = jsniMethods.get(x);
      assert jsniMethod != null;
      SourceInfo info = method.getSourceInfo();
      JsFunction jsFunction = jsniMethod.function();
      JsniMethodBody body = new JsniMethodBody(info);
      method.setBody(body);
      jsFunction.setFromJava(true);
      body.setFunc(jsFunction);
      // Resolve locals, params, and JSNI.
      JsParameterResolver localResolver = new JsParameterResolver(jsFunction);
      localResolver.accept(jsFunction);
      JsniResolver jsniResolver = new JsniResolver(body);
      jsniResolver.accept(jsFunction);
    }

    private void processSuperCallLocalArgs(ReferenceBinding superClass, JMethodCall call) {
      if (superClass.syntheticOuterLocalVariables() != null) {
        for (SyntheticArgumentBinding arg : superClass.syntheticOuterLocalVariables()) {
          // TODO: use emulation path here.
          // Got to be one of my params
          JType varType = typeMap.get(arg.type);
          String varName = intern(arg.name);
          JParameter param = null;
          for (JParameter paramIt : curMethod.method.getParams()) {
            if (varType == paramIt.getType() && varName.equals(paramIt.getName())) {
              param = paramIt;
            }
          }
          if (param == null) {
            throw new InternalCompilerException(
                "Could not find matching local arg for explicit super ctor call.");
          }
          call.addArg(new JParameterRef(call.getSourceInfo(), param));
        }
      }
    }

    // Only called on nested instances constructors (explicitConstructorCalls) that are of the
    // form: outer.super(...) or super(...)
    //
    // Will set outer (in the first case) or the implicit enclosing object reference to
    // be the first parameter of super(...)
    private void processSuperCallThisArgs(ReferenceBinding superClass, JMethodCall call,
        JExpression qualifier, Expression qualification) {
      // Explicit super calls can only happend inside constructors
      assert curMethod.scope.isInsideConstructor();
      if (superClass.syntheticEnclosingInstanceTypes() != null) {
        // there can only be ONE immediate enclosing instance.
        assert superClass.syntheticEnclosingInstanceTypes().length == 1;
        ReferenceBinding targetType = superClass.syntheticEnclosingInstanceTypes()[0];
        if (qualification != null) {
          // Outer object is the qualifier.
          call.addArg(qualifier);
        } else {
          // Get implicit outer object.
          call.addArg(makeThisReference(call.getSourceInfo(), targetType, false, curMethod.scope));
        }
      }
    }

    private void processThisCallLocalArgs(ReferenceBinding binding, JMethodCall call) {
      if (binding.syntheticOuterLocalVariables() != null) {
        for (SyntheticArgumentBinding arg : binding.syntheticOuterLocalVariables()) {
          JParameter param = (JParameter) curMethod.locals.get(arg);
          assert param != null;
          call.addArg(new JParameterRef(call.getSourceInfo(), param));
        }
      }
    }

    private void processThisCallThisArgs(ReferenceBinding binding, JMethodCall call) {
      if (binding.syntheticEnclosingInstanceTypes() != null) {
        Iterator<JParameter> paramIt = curMethod.method.getParams().iterator();
        if (curClass.classType.isEnumOrSubclass() != null) {
          // Skip past the enum args.
          paramIt.next();
          paramIt.next();
        }
        for (@SuppressWarnings("unused")
        ReferenceBinding argType : binding.syntheticEnclosingInstanceTypes()) {
          JParameter param = paramIt.next();
          call.addArg(new JParameterRef(call.getSourceInfo(), param));
        }
      }
    }

    private void push(JNode node) {
      nodeStack.add(node);
    }

    private void pushBinaryOp(Expression x, JBinaryOperator op, Expression lhs, Expression rhs) {
      try {
        JType type = typeMap.get(x.resolvedType);
        SourceInfo info = makeSourceInfo(x);
        JExpression exprArg2 = pop(rhs);
        JExpression exprArg1 = pop(lhs);
        push(new JBinaryOperation(info, type, op, exprArg1, exprArg2));
      } catch (Throwable e) {
        throw translateException(x, e);
      }
    }

    private void pushInitializerMethodInfo(FieldDeclaration x, MethodScope scope) {
      JMethod initMeth;
      if (x.isStatic()) {
        initMeth = curClass.type.getClinitMethod();
      } else {
        initMeth = curClass.type.getInitMethod();
      }
      pushMethodInfo(new MethodInfo(initMeth, (JMethodBody) initMeth.getBody(), scope));
    }

    private void pushMethodInfo(MethodInfo newInfo) {
      methodStack.push(curMethod);
      curMethod = newInfo;
    }

    private void pushNewExpression(SourceInfo info, AllocationExpression x, Expression qualifier,
        List<JExpression> arguments, BlockScope scope) {
      TypeBinding typeBinding = x.resolvedType;
      if (typeBinding.constantPoolName() == null) {
        /*
         * Weird case: if JDT determines that this local class is totally
         * uninstantiable, it won't bother allocating a local name.
         */
        push(JNullLiteral.INSTANCE);
        return;
      }
      assert typeBinding.isClass() || typeBinding.isEnum();

      MethodBinding b = x.binding;
      assert b.isConstructor();
      JConstructor ctor = (JConstructor) typeMap.get(b);
      JMethodCall call = new JNewInstance(info, ctor, curClass.type);
      JExpression qualExpr = pop(qualifier);

      // Enums: hidden arguments for the name and id.
      if (x.enumConstant != null) {
        call.addArgs(getStringLiteral(info, x.enumConstant.name), JIntLiteral
            .get(x.enumConstant.binding.original().id));
      }

      // Synthetic args for inner classes
      ReferenceBinding targetBinding = (ReferenceBinding) b.declaringClass.erasure();
      boolean isNested = isNested(targetBinding);
      if (isNested) {
        // Synthetic this args for inner classes
        if (targetBinding.syntheticEnclosingInstanceTypes() != null) {
          ReferenceBinding checkedTargetType =
              targetBinding.isAnonymousType() ? (ReferenceBinding) targetBinding.superclass()
                  .erasure() : targetBinding;
          ReferenceBinding targetEnclosingType = checkedTargetType.enclosingType();
          for (ReferenceBinding argType : targetBinding.syntheticEnclosingInstanceTypes()) {
            argType = (ReferenceBinding) argType.erasure();
            if (qualifier != null && argType == targetEnclosingType) {
              call.addArg(qualExpr);
            } else {
              JExpression thisRef = makeThisReference(info, argType, false, scope);
              call.addArg(thisRef);
            }
          }
        }
      }

      // Plain old regular user arguments
      call.addArgs(arguments);

      // Synthetic args for inner classes
      if (isNested) {
        // Synthetic locals for local classes
        if (targetBinding.syntheticOuterLocalVariables() != null) {
          for (SyntheticArgumentBinding arg : targetBinding.syntheticOuterLocalVariables()) {
            LocalVariableBinding targetVariable = arg.actualOuterLocalVariable;
            VariableBinding[] path = scope.getEmulationPath(targetVariable);
            assert path.length == 1;
            if (curMethod.scope.isInsideInitializer()
                && path[0] instanceof SyntheticArgumentBinding) {
              SyntheticArgumentBinding sb = (SyntheticArgumentBinding) path[0];
              JField field = curClass.syntheticFields.get(sb);
              assert field != null;
              call.addArg(makeInstanceFieldRef(info, field));
            } else if (path[0] instanceof LocalVariableBinding) {
              JExpression localRef = makeLocalRef(info, (LocalVariableBinding) path[0]);
              call.addArg(localRef);
            } else if (path[0] instanceof FieldBinding) {
              JField field = typeMap.get((FieldBinding) path[0]);
              assert field != null;
              call.addArg(makeInstanceFieldRef(info, field));
            } else {
              throw new InternalCompilerException("Unknown emulation path.");
            }
          }
        }
      }

      if (ctor.getEnclosingType() == javaLangString) {
        /*
         * MAGIC: java.lang.String is implemented as a JavaScript String
         * primitive with a modified prototype. This requires funky handling of
         * constructor calls. We find a method named _String() whose signature
         * matches the requested constructor
         * 
         * TODO(scottb): consider moving this to a later pass.
         */
        MethodBinding staticBinding =
            targetBinding.getExactMethod(_STRING, b.parameters, curCud.scope);
        assert staticBinding.isStatic();
        JMethod staticMethod = typeMap.get(staticBinding);
        JMethodCall newCall = new JMethodCall(info, null, staticMethod);
        newCall.addArgs(call.getArgs());
        call = newCall;
      }

      push(call);
    }

    /**
     * Don't process unreachable statements, because JDT doesn't always fully
     * resolve them, which can crash us.
     */
    private Statement[] reduceToReachable(Statement[] statements) {
      if (statements == null) {
        return null;
      }
      int reachableCount = 0;
      for (Statement statement : statements) {
        if ((statement.bits & ASTNode.IsReachable) != 0) {
          ++reachableCount;
        }
      }
      if (reachableCount == statements.length) {
        return statements;
      }
      Statement[] newStatments = new Statement[reachableCount];
      int index = 0;
      for (Statement statement : statements) {
        if ((statement.bits & ASTNode.IsReachable) != 0) {
          newStatments[index++] = statement;
        }
      }
      return newStatments;
    }

    private JExpression resolveNameReference(NameReference x, BlockScope scope) {
      SourceInfo info = makeSourceInfo(x);
      if (x.constant != Constant.NotAConstant) {
        return getConstant(info, x.constant);
      }
      Binding binding = x.binding;
      JExpression result = null;
      if (binding instanceof LocalVariableBinding) {
        LocalVariableBinding b = (LocalVariableBinding) binding;
        if ((x.bits & ASTNode.DepthMASK) != 0) {
          VariableBinding[] path = scope.getEmulationPath(b);
          if (path == null) {
            /*
             * Don't like this, but in rare cases (e.g. the variable is only
             * ever used as an unnecessary qualifier) JDT provides no emulation
             * to the desired variable.
             */
            // throw new InternalCompilerException("No emulation path.");
            return null;
          }
          assert path.length == 1;
          if (curMethod.scope.isInsideInitializer() && path[0] instanceof SyntheticArgumentBinding) {
            SyntheticArgumentBinding sb = (SyntheticArgumentBinding) path[0];
            JField field = curClass.syntheticFields.get(sb);
            assert field != null;
            result = makeInstanceFieldRef(info, field);
          } else if (path[0] instanceof LocalVariableBinding) {
            result = makeLocalRef(info, (LocalVariableBinding) path[0]);
          } else if (path[0] instanceof FieldBinding) {
            FieldBinding fb = (FieldBinding) path[0];
            assert curClass.typeDecl.binding.isCompatibleWith(x.actualReceiverType.erasure());
            JField field = typeMap.get(fb);
            assert field != null;
            result = makeInstanceFieldRef(info, field);
          } else {
            throw new InternalCompilerException("Unknown emulation path.");
          }
        } else {
          result = makeLocalRef(info, b);
        }
      } else if (binding instanceof FieldBinding) {
        FieldBinding b = ((FieldBinding) x.binding).original();
        JField field = typeMap.get(b);
        assert field != null;
        JExpression thisRef = null;
        if (!b.isStatic()) {
          thisRef = makeThisReference(info, (ReferenceBinding) x.actualReceiverType, false, scope);
        }
        result = new JFieldRef(info, thisRef, field, curClass.type);
      } else {
        return null;
      }
      assert result != null;
      return result;
    }

    private JExpression simplify(JExpression result, Expression x) {
      if (x.constant != null && x.constant != Constant.NotAConstant) {
        // Prefer JDT-computed constant value to the actual written expression.
        result = getConstant(result.getSourceInfo(), x.constant);
      }
      return maybeBoxOrUnbox(result, x.implicitConversion);
    }

    private JExpression unbox(JExpression original, int implicitConversion) {
      int typeId = implicitConversion & TypeIds.COMPILE_TYPE_MASK;
      ClassScope scope = curClass.scope;
      BaseTypeBinding primitiveType = (BaseTypeBinding) TypeBinding.wellKnownType(scope, typeId);
      ReferenceBinding boxType = (ReferenceBinding) scope.boxing(primitiveType);
      char[] selector = CharOperation.concat(primitiveType.simpleName, VALUE);
      MethodBinding valueMethod =
          boxType.getExactMethod(selector, NO_TYPES, scope.compilationUnitScope());
      assert valueMethod != null;
      JMethod unboxMethod = typeMap.get(valueMethod);
      JMethodCall call = new JMethodCall(original.getSourceInfo(), original, unboxMethod);
      return call;
    }

    private void writeEnumValueOfMethod(JEnumType type, JMethod method, JField valuesField) {
      JField mapField;
      TypeBinding mapType;
      ReferenceBinding enumType = curCud.scope.getJavaLangEnum();
      {
        /*
         * Make an inner class to hold a lazy-init name-value map. We use a
         * class to take advantage of its clinit.
         * 
         * class Map { $MAP = Enum.createValueOfMap($VALUES); }
         */
        SourceInfo info = type.getSourceInfo();
        JClassType mapClass = new JClassType(info, intern(type.getName() + "$Map"), false, true);
        mapClass.setSuperClass(javaLangObject);
        mapClass.setEnclosingType(type);
        newTypes.add(mapClass);

        MethodBinding[] createValueOfMapBindings = enumType.getMethods(CREATE_VALUE_OF_MAP);
        assert createValueOfMapBindings.length == 1;
        MethodBinding createValueOfMapBinding = createValueOfMapBindings[0];
        mapType = createValueOfMapBinding.returnType;

        mapField =
            new JField(info, "$MAP", mapClass, typeMap.get(mapType), true, Disposition.FINAL);
        mapClass.addField(mapField);

        JMethodCall call = new JMethodCall(info, null, typeMap.get(createValueOfMapBinding));
        call.addArg(new JFieldRef(info, null, valuesField, mapClass));
        JFieldRef mapRef = new JFieldRef(info, null, mapField, mapClass);
        JDeclarationStatement declStmt = new JDeclarationStatement(info, mapRef, call);
        JMethod clinit =
            createSyntheticMethod(info, "$clinit", mapClass, JPrimitiveType.VOID, false, true,
                true, AccessModifier.PRIVATE);
        JBlock clinitBlock = ((JMethodBody) clinit.getBody()).getBlock();
        clinitBlock.addStmt(declStmt);
      }

      /*
       * return Enum.valueOf(Enum$Map.Map.$MAP, name);
       */
      {
        SourceInfo info = method.getSourceInfo();

        MethodBinding valueOfBinding =
            enumType.getExactMethod(VALUE_OF, new TypeBinding[]{
                mapType, curCud.scope.getJavaLangString()}, curCud.scope);
        assert valueOfBinding != null;

        JFieldRef mapRef = new JFieldRef(info, null, mapField, type);
        JParameterRef nameRef = new JParameterRef(info, method.getParams().get(0));
        JMethodCall call = new JMethodCall(info, null, typeMap.get(valueOfBinding));
        call.addArgs(mapRef, nameRef);
        implementMethod(method, call);
      }
    }

    private void writeEnumValuesMethod(JEnumType type, JMethod method, JField valuesField) {
      // return $VALUES;
      JFieldRef valuesRef = new JFieldRef(method.getSourceInfo(), null, valuesField, type);
      implementMethod(method, valuesRef);
    }
  }

  static class ClassInfo {
    public final JClassType classType;
    public final ClassScope scope;
    public final Map<SyntheticArgumentBinding, JField> syntheticFields =
        new IdentityHashMap<SyntheticArgumentBinding, JField>();
    public final JDeclaredType type;
    public final TypeDeclaration typeDecl;

    public ClassInfo(JDeclaredType type, TypeDeclaration x) {
      this.type = type;
      this.classType = (type instanceof JClassType) ? (JClassType) type : null;
      this.typeDecl = x;
      this.scope = x.scope;
    }
  }

  static class CudInfo {
    public final String fileName;
    public final CompilationUnitScope scope;
    public final int[] separatorPositions;

    public CudInfo(CompilationUnitDeclaration cud) {
      fileName = intern(cud.getFileName());
      separatorPositions = cud.compilationResult().getLineSeparatorPositions();
      scope = cud.scope;
    }
  }

  static class MethodInfo {
    public final JMethodBody body;
    public final Map<String, JLabel> labels = new HashMap<String, JLabel>();
    public final Map<LocalVariableBinding, JVariable> locals =
        new IdentityHashMap<LocalVariableBinding, JVariable>();
    public final JMethod method;
    public final MethodScope scope;

    public MethodInfo(JMethod method, JMethodBody methodBody, MethodScope methodScope) {
      this.method = method;
      this.body = methodBody;
      this.scope = methodScope;
    }
  }

  /**
   * Manually tracked version count.
   * 
   * TODO(zundel): something much more awesome?
   */
  private static final long AST_VERSION = 3;
  private static final char[] _STRING = "_String".toCharArray();
  private static final String ARRAY_LENGTH_FIELD = "length";

  /**
   * Reflective access to {@link ForeachStatement#collectionElementType}.
   */
  private static final Field collectionElementTypeField;

  private static final char[] CREATE_VALUE_OF_MAP = "createValueOfMap".toCharArray();
  private static final char[] HAS_NEXT = "hasNext".toCharArray();
  private static final char[] ITERATOR = "iterator".toCharArray();
  private static final char[] NEXT = "next".toCharArray();
  private static final TypeBinding[] NO_TYPES = new TypeBinding[0];
  private static final char[] ORDINAL = "ordinal".toCharArray();
  private static final StringInterner stringInterner = StringInterner.get();
  private static final char[] VALUE = "Value".toCharArray();
  private static final char[] VALUE_OF = "valueOf".toCharArray();
  private static final char[] VALUES = "values".toCharArray();

  static {
    InternalCompilerException.preload();
    try {
      collectionElementTypeField = ForeachStatement.class.getDeclaredField("collectionElementType");
      collectionElementTypeField.setAccessible(true);
    } catch (Exception e) {
      throw new RuntimeException(
          "Unexpectedly unable to access ForeachStatement.collectionElementType via reflection", e);
    }
  }

  /**
   * Returns a serialization version number. Used to determine if the AST
   * contained within cached compilation units is compatible with the current
   * version of GWT.
   */
  public static long getSerializationVersion() {
    // TODO(zundel): something much awesomer.
    return AST_VERSION;
  }

  static String dotify(char[][] name) {
    StringBuffer result = new StringBuffer();
    for (int i = 0; i < name.length; ++i) {
      if (i > 0) {
        result.append('.');
      }

      result.append(name[i]);
    }
    return result.toString();
  }

  static Disposition getFieldDisposition(FieldBinding binding) {
    Disposition disposition;
    if (isCompileTimeConstant(binding)) {
      disposition = Disposition.COMPILE_TIME_CONSTANT;
    } else if (binding.isFinal()) {
      disposition = Disposition.FINAL;
    } else if (binding.isVolatile()) {
      disposition = Disposition.VOLATILE;
    } else {
      disposition = Disposition.NONE;
    }
    return disposition;
  }

  static String intern(char[] cs) {
    return intern(String.valueOf(cs));
  }

  static String intern(String s) {
    return stringInterner.intern(s);
  }

  static boolean isNested(ReferenceBinding binding) {
    return binding.isNestedType() && !binding.isStatic();
  }

  private static boolean isCompileTimeConstant(FieldBinding binding) {
    assert !binding.isFinal() || !binding.isVolatile();
    boolean isCompileTimeConstant =
        binding.isStatic() && binding.isFinal() && (binding.constant() != Constant.NotAConstant);
    if (isCompileTimeConstant) {
      assert binding.type.isBaseType() || (binding.type.id == TypeIds.T_JavaLangString);
    }
    return isCompileTimeConstant;
  }

  /**
   * Returns <code>true</code> if JDT optimized the condition to
   * <code>false</code>.
   */
  private static boolean isOptimizedFalse(Expression condition) {
    if (condition != null) {
      Constant cst = condition.optimizedBooleanConstant();
      if (cst != Constant.NotAConstant) {
        if (cst.booleanValue() == false) {
          return true;
        }
      }
    }
    return false;
  }

  /**
   * Returns <code>true</code> if JDT optimized the condition to
   * <code>true</code>.
   */
  private static boolean isOptimizedTrue(Expression condition) {
    if (condition != null) {
      Constant cst = condition.optimizedBooleanConstant();
      if (cst != Constant.NotAConstant) {
        if (cst.booleanValue()) {
          return true;
        }
      }
    }
    return false;
  }

  Map<TypeDeclaration, Binding[]> artificialRescues;

  CudInfo curCud = null;

  JClassType javaLangClass = null;

  JClassType javaLangObject = null;

  JClassType javaLangString = null;

  Map<MethodDeclaration, JsniMethod> jsniMethods;

  Map<String, Binding> jsniRefs;

  final ReferenceMapper typeMap = new ReferenceMapper();

  private final AstVisitor astVisitor = new AstVisitor();

  private List<JDeclaredType> newTypes;

  private String sourceMapPath;

  /**
   * Builds all the GWT AST nodes that correspond to one Java source file.
   *
   * @param cud The compiled form of the Java source from the JDT.
   * @param sourceMapPath the path that should be included in a sourcemap.
   * @param artificialRescues Used to decorate the AST.
   * @param jsniMethods Native methods to add to the AST.
   * @param jsniRefs Map from JSNI references to their JDT definitions.
   * @return All the types seen in this source file.
   */
  public List<JDeclaredType> process(CompilationUnitDeclaration cud, String sourceMapPath,
      Map<TypeDeclaration, Binding[]> artificialRescues,
      Map<MethodDeclaration, JsniMethod> jsniMethods, Map<String, Binding> jsniRefs) {
    if (cud.types == null) {
      return Collections.emptyList();
    }
    this.sourceMapPath = sourceMapPath;
    this.artificialRescues = artificialRescues;
    this.jsniRefs = jsniRefs;
    this.jsniMethods = jsniMethods;
    newTypes = new ArrayList<JDeclaredType>();
    curCud = new CudInfo(cud);

    for (TypeDeclaration typeDecl : cud.types) {
      createTypes(typeDecl);
    }

    // Now that types exist, cache Object, String, etc.
    javaLangObject = (JClassType) typeMap.get(cud.scope.getJavaLangObject());
    javaLangString = (JClassType) typeMap.get(cud.scope.getJavaLangString());
    javaLangClass = (JClassType) typeMap.get(cud.scope.getJavaLangClass());

    for (TypeDeclaration typeDecl : cud.types) {
      // Resolve super type / interface relationships.
      resolveTypeRefs(typeDecl);
    }
    for (TypeDeclaration typeDecl : cud.types) {
      // Create fields and empty methods.
      createMembers(typeDecl);
    }
    for (TypeDeclaration typeDecl : cud.types) {
      // Build the code.
      typeDecl.traverse(astVisitor, cud.scope);
    }

    List<JDeclaredType> result = newTypes;

    // Clean up.
    typeMap.clearSource();
    this.jsniRefs = jsniRefs;
    this.jsniMethods = jsniMethods;
    newTypes = null;
    curCud = null;
    javaLangObject = null;
    javaLangString = null;
    javaLangClass = null;

    return result;
  }

  SourceInfo makeSourceInfo(AbstractMethodDeclaration x) {
    int startLine =
        Util.getLineNumber(x.sourceStart, curCud.separatorPositions, 0,
            curCud.separatorPositions.length - 1);
    return SourceOrigin.create(x.sourceStart, x.bodyEnd, startLine, sourceMapPath);
  }

  SourceInfo makeSourceInfo(ASTNode x) {
    int startLine =
        Util.getLineNumber(x.sourceStart, curCud.separatorPositions, 0,
            curCud.separatorPositions.length - 1);
    return SourceOrigin.create(x.sourceStart, x.sourceEnd, startLine, sourceMapPath);
  }

  InternalCompilerException translateException(ASTNode node, Throwable e) {
    if (e instanceof VirtualMachineError) {
      // Always rethrow VM errors (an attempt to wrap may fail).
      throw (VirtualMachineError) e;
    }
    InternalCompilerException ice;
    if (e instanceof InternalCompilerException) {
      ice = (InternalCompilerException) e;
    } else {
      ice = new InternalCompilerException("Error constructing Java AST", e);
    }
    if (node != null) {
      ice.addNode(node.getClass().getName(), node.toString(), makeSourceInfo(node));
    }
    return ice;
  }

  private void createField(FieldDeclaration x) {
    if (x instanceof Initializer) {
      return;
    }
    SourceInfo info = makeSourceInfo(x);
    FieldBinding binding = x.binding;
    JType type = typeMap.get(binding.type);
    JDeclaredType enclosingType = (JDeclaredType) typeMap.get(binding.declaringClass);

    JField field;
    if (x.initialization != null && x.initialization instanceof AllocationExpression
        && ((AllocationExpression) x.initialization).enumConstant != null) {
      field =
          new JEnumField(info, intern(binding.name), binding.original().id,
              (JEnumType) enclosingType, (JClassType) type);
    } else {
      field =
          new JField(info, intern(binding.name), enclosingType, type, binding.isStatic(),
              getFieldDisposition(binding));
    }
    enclosingType.addField(field);
    typeMap.setField(binding, field);
  }

  private void createMembers(TypeDeclaration x) {
    SourceTypeBinding binding = x.binding;
    JDeclaredType type = (JDeclaredType) typeMap.get(binding);
    SourceInfo info = type.getSourceInfo();
    try {
      /**
       * We emulate static initializers and instance initializers as methods. As
       * in other cases, this gives us: simpler AST, easier to optimize, more
       * like output JavaScript. Clinit is always in slot 0, init (if it exists)
       * is always in slot 1.
       */
      assert type.getMethods().size() == 0;
      createSyntheticMethod(info, "$clinit", type, JPrimitiveType.VOID, false, true, true,
          AccessModifier.PRIVATE);

      if (type instanceof JClassType) {
        assert type.getMethods().size() == 1;
        createSyntheticMethod(info, "$init", type, JPrimitiveType.VOID, false, false, true,
            AccessModifier.PRIVATE);

        // Add a getClass() implementation for all non-Object classes.
        if (type != javaLangObject && !JSORestrictionsChecker.isJsoSubclass(binding)) {
          assert type.getMethods().size() == 2;
          createSyntheticMethod(info, "getClass", type, javaLangClass, false, false, false,
              AccessModifier.PUBLIC);
        }
      }

      if (type instanceof JEnumType) {
        {
          assert type.getMethods().size() == 3;
          MethodBinding valueOfBinding =
              binding.getExactMethod(VALUE_OF, new TypeBinding[]{x.scope.getJavaLangString()},
                  curCud.scope);
          assert valueOfBinding != null;
          createSyntheticMethodFromBinding(info, valueOfBinding, new String[]{"name"});
        }
        {
          assert type.getMethods().size() == 4;
          MethodBinding valuesBinding = binding.getExactMethod(VALUES, NO_TYPES, curCud.scope);
          assert valuesBinding != null;
          createSyntheticMethodFromBinding(info, valuesBinding, null);
        }
      }

      if (x.fields != null) {
        for (FieldDeclaration field : x.fields) {
          if (x.binding.isLocalType() && field.isStatic()) {
            /*
             * Source compatibility with genJavaAst; static fields in local
             * types don't get visited.
             */
          } else {
            createField(field);
          }
        }
      }

      if (x.methods != null) {
        for (AbstractMethodDeclaration method : x.methods) {
          createMethod(method);
        }
      }

      if (x.memberTypes != null) {
        for (TypeDeclaration memberType : x.memberTypes) {
          createMembers(memberType);
        }
      }
    } catch (Throwable e) {
      InternalCompilerException ice = translateException(null, e);
      StringBuffer sb = new StringBuffer();
      x.printHeader(0, sb);
      ice.addNode(x.getClass().getName(), sb.toString(), type.getSourceInfo());
      throw ice;
    }
  }

  private void createMethod(AbstractMethodDeclaration x) {
    if (x instanceof Clinit) {
      return;
    }
    SourceInfo info = makeSourceInfo(x);
    MethodBinding b = x.binding;
    ReferenceBinding declaringClass = (ReferenceBinding) b.declaringClass.erasure();
    Set<String> alreadyNamedVariables = new HashSet<String>();
    JDeclaredType enclosingType = (JDeclaredType) typeMap.get(declaringClass);
    assert !enclosingType.isExternal();
    JMethod method;
    boolean isNested = isNested(declaringClass);
    if (x.isConstructor()) {
      method = new JConstructor(info, (JClassType) enclosingType);
      if (x.binding.declaringClass.isEnum()) {
        // Enums have hidden arguments for name and value
        method.addParam(new JParameter(info, "enum$name", typeMap.get(x.scope.getJavaLangString()),
            true, false, method));
        method.addParam(new JParameter(info, "enum$ordinal", JPrimitiveType.INT, true, false,
            method));
      }
      // add synthetic args for outer this
      if (isNested) {
        NestedTypeBinding nestedBinding = (NestedTypeBinding) declaringClass;
        if (nestedBinding.enclosingInstances != null) {
          for (int i = 0; i < nestedBinding.enclosingInstances.length; ++i) {
            SyntheticArgumentBinding arg = nestedBinding.enclosingInstances[i];
            String argName = String.valueOf(arg.name);
            if (alreadyNamedVariables.contains(argName)) {
              argName += "_" + i;
            }
            createParameter(info, arg, argName, method);
            alreadyNamedVariables.add(argName);
          }
        }
      }
    } else {
      method =
          new JMethod(info, intern(b.selector), enclosingType, typeMap.get(b.returnType), b
              .isAbstract(), b.isStatic(), b.isFinal(), AccessModifier.fromMethodBinding(b));
    }

    // User args.
    createParameters(method, x);

    if (x.isConstructor()) {
      if (isNested) {
        // add synthetic args for locals
        NestedTypeBinding nestedBinding = (NestedTypeBinding) declaringClass;
        // add synthetic args for outer this and locals
        if (nestedBinding.outerLocalVariables != null) {
          for (int i = 0; i < nestedBinding.outerLocalVariables.length; ++i) {
            SyntheticArgumentBinding arg = nestedBinding.outerLocalVariables[i];
            String argName = String.valueOf(arg.name);
            if (alreadyNamedVariables.contains(argName)) {
              argName += "_" + i;
            }
            createParameter(info, arg, argName, method);
            alreadyNamedVariables.add(argName);
          }
        }
      }
    }

    mapExceptions(method, b);

    if (b.isSynthetic()) {
      method.setSynthetic();
    }
    enclosingType.addMethod(method);
    typeMap.setMethod(b, method);
  }

  private void createParameter(SourceInfo info, LocalVariableBinding binding, JMethod method) {
    createParameter(info, binding, intern(binding.name), method);
  }

  private void createParameter(SourceInfo info, LocalVariableBinding binding, String name,
      JMethod method) {
    JParameter param =
        new JParameter(info, name, typeMap.get(binding.type), binding.isFinal(), false, method);
    method.addParam(param);
  }

  private void createParameters(JMethod method, AbstractMethodDeclaration x) {
    if (x.arguments != null) {
      for (Argument argument : x.arguments) {
        SourceInfo info = makeSourceInfo(argument);
        LocalVariableBinding binding = argument.binding;
        createParameter(info, binding, method);
      }
    }
    method.freezeParamTypes();
  }

  private JMethod createSyntheticMethod(SourceInfo info, String name, JDeclaredType enclosingType,
      JType returnType, boolean isAbstract, boolean isStatic, boolean isFinal, AccessModifier access) {
    JMethod method =
        new JMethod(info, name, enclosingType, returnType, isAbstract, isStatic, isFinal, access);
    method.freezeParamTypes();
    method.setSynthetic();
    method.setBody(new JMethodBody(info));
    enclosingType.addMethod(method);
    return method;
  }

  private JMethod createSyntheticMethodFromBinding(SourceInfo info, MethodBinding binding,
      String[] paramNames) {
    JMethod method = typeMap.createMethod(info, binding, paramNames);
    assert !method.isExternal();
    method.setBody(new JMethodBody(info));
    typeMap.setMethod(binding, method);
    return method;
  }

  private void createTypes(TypeDeclaration x) {
    SourceInfo info = makeSourceInfo(x);
    try {
      SourceTypeBinding binding = x.binding;
      String name;
      if (binding instanceof LocalTypeBinding) {
        char[] localName = binding.constantPoolName();
        name = new String(localName).replace('/', '.');
      } else {
        name = dotify(binding.compoundName);
      }
      name = intern(name);
      JDeclaredType type;
      if (binding.isClass()) {
        type = new JClassType(info, name, binding.isAbstract(), binding.isFinal());
      } else if (binding.isInterface() || binding.isAnnotationType()) {
        type = new JInterfaceType(info, name);
      } else if (binding.isEnum()) {
        if (binding.isAnonymousType()) {
          // Don't model an enum subclass as a JEnumType.
          type = new JClassType(info, name, false, true);
        } else {
          type = new JEnumType(info, name, binding.isAbstract());
        }
      } else {
        throw new InternalCompilerException("ReferenceBinding is not a class, interface, or enum.");
      }
      typeMap.setSourceType(binding, type);
      newTypes.add(type);
      if (x.memberTypes != null) {
        for (TypeDeclaration memberType : x.memberTypes) {
          createTypes(memberType);
        }
      }
    } catch (Throwable e) {
      InternalCompilerException ice = translateException(null, e);
      StringBuffer sb = new StringBuffer();
      x.printHeader(0, sb);
      ice.addNode(x.getClass().getName(), sb.toString(), info);
      throw ice;
    }
  }

  private void mapExceptions(JMethod method, MethodBinding binding) {
    for (ReferenceBinding thrownBinding : binding.thrownExceptions) {
      JClassType type = (JClassType) typeMap.get(thrownBinding);
      method.addThrownException(type);
    }
  }

  private void resolveTypeRefs(TypeDeclaration x) {
    SourceTypeBinding binding = x.binding;
    JDeclaredType type = (JDeclaredType) typeMap.get(binding);
    try {
      ReferenceBinding superClassBinding = binding.superclass();
      if (type instanceof JClassType && superClassBinding != null) {
        assert (binding.superclass().isClass() || binding.superclass().isEnum());
        JClassType superClass = (JClassType) typeMap.get(superClassBinding);
        ((JClassType) type).setSuperClass(superClass);
      }

      ReferenceBinding[] superInterfaces = binding.superInterfaces();
      for (ReferenceBinding superInterfaceBinding : superInterfaces) {
        assert (superInterfaceBinding.isInterface());
        JInterfaceType superInterface = (JInterfaceType) typeMap.get(superInterfaceBinding);
        type.addImplements(superInterface);
      }

      ReferenceBinding enclosingBinding = binding.enclosingType();
      if (enclosingBinding != null) {
        type.setEnclosingType((JDeclaredType) typeMap.get(enclosingBinding));
      }
      if (x.memberTypes != null) {
        for (TypeDeclaration memberType : x.memberTypes) {
          resolveTypeRefs(memberType);
        }
      }
    } catch (Throwable e) {
      InternalCompilerException ice = translateException(null, e);
      StringBuffer sb = new StringBuffer();
      x.printHeader(0, sb);
      ice.addNode(x.getClass().getName(), sb.toString(), type.getSourceInfo());
      throw ice;
    }
  }
}