| /* |
| * Copyright 2008 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.shell; |
| |
| import com.google.gwt.dev.javac.JsniMethod; |
| import com.google.gwt.dev.jjs.SourceInfo; |
| import com.google.gwt.dev.js.JsSourceGenerationVisitor; |
| 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.JsInvocation; |
| import com.google.gwt.dev.js.ast.JsNameRef; |
| import com.google.gwt.dev.js.ast.JsNode; |
| import com.google.gwt.dev.js.ast.JsNullLiteral; |
| import com.google.gwt.dev.js.ast.JsNumberLiteral; |
| import com.google.gwt.dev.util.DefaultTextOutput; |
| import com.google.gwt.dev.util.TextOutput; |
| |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.Field; |
| import java.lang.reflect.Member; |
| import java.lang.reflect.Method; |
| import java.util.List; |
| |
| /** |
| * Helper methods working with JSNI. |
| */ |
| public class Jsni { |
| |
| /** |
| * Generate source code, fixing up any JSNI references for hosted mode. |
| * |
| * <p/> |
| * <table> |
| * <tr> |
| * <td>Original</td> |
| * <td>Becomes</td> |
| * </tr> |
| * <tr> |
| * <td><code>obj.@class::method(params)(args)</code></td> |
| * |
| * <td><code>__gwt_makeJavaInvoke(paramCount)(obj, dispId, args)</code></td> |
| * </tr> |
| * <tr> |
| * <td><code>@class::method(params)(args)</code></td> |
| * |
| * <td><code>__gwt_makeJavaInvoke(paramCount)(null, dispId, args)</code></td> |
| * </tr> |
| * <tr> |
| * <td><code>obj.@class::method(params)</code></td> |
| * |
| * <td><code>__gwt_makeTearOff(obj, dispId, paramCount)</code></td> |
| * </tr> |
| * <tr> |
| * <td><code>@class::method(params)</code></td> |
| * |
| * <td><code>__gwt_makeTearOff(null, dispId, paramCount)</code></td> |
| * </tr> |
| * <tr> |
| * <td><code>obj.@class::field</code></td> |
| * |
| * <td><code>obj[dispId]</code></td> |
| * </tr> |
| * <tr> |
| * <td><code>@class::field</code></td> |
| * |
| * <td><code>__static[dispId]</code></td> |
| * </tr> |
| * </table> |
| */ |
| private static class JsSourceGenWithJsniIdentFixup extends |
| JsSourceGenerationVisitor { |
| private final DispatchIdOracle dispatchInfo; |
| private final TextOutput out; |
| |
| public JsSourceGenWithJsniIdentFixup(TextOutput out, DispatchIdOracle ccl) { |
| super(out); |
| this.dispatchInfo = ccl; |
| this.out = out; |
| } |
| |
| /** |
| * This will handle references to fields or tear-offs of Java methods. |
| */ |
| @Override |
| public boolean visit(JsNameRef x, JsContext ctx) { |
| String ident = x.getIdent(); |
| JsExpression q = x.getQualifier(); |
| if (ident.startsWith("@")) { |
| int dispId = dispatchInfo.getDispId(ident); |
| |
| Member member; |
| if (dispId < 0) { |
| member = null; |
| } else { |
| member = dispatchInfo.getClassInfoByDispId(dispId).getMember(dispId); |
| } |
| |
| if (member == null) { |
| throw new HostedModeException( |
| "JSNI rewriter found reference to non-existent field in a field reference or java method tear-off: " |
| + ident + " at " + x.getSourceInfo()); |
| } |
| |
| if (member instanceof Field || member instanceof SyntheticClassMember) { |
| if (q != null) { |
| accept(q); |
| out.print("["); |
| out.print(String.valueOf(dispId)); |
| out.print("]"); |
| } else { |
| out.print("__static["); |
| out.print(String.valueOf(dispId)); |
| out.print("]"); |
| } |
| |
| return false; |
| } |
| |
| int paramCount = 0; |
| if (member instanceof Method) { |
| paramCount = ((Method) member).getParameterTypes().length; |
| } else if (member instanceof Constructor<?>) { |
| paramCount = ((Constructor<?>) member).getParameterTypes().length; |
| } |
| |
| // Use a clone instead of modifying the original JSNI |
| // __gwt_makeTearOff(obj, dispId, paramCount) |
| SourceInfo info = x.getSourceInfo(); |
| JsInvocation rewritten = new JsInvocation(info, new JsNameRef(info, "__gwt_makeTearOff")); |
| |
| List<JsExpression> arguments = rewritten.getArguments(); |
| if (q == null) { |
| q = JsNullLiteral.INSTANCE; |
| } |
| arguments.add(q); |
| arguments.add(new JsNumberLiteral(info, dispId)); |
| arguments.add(new JsNumberLiteral(info, paramCount)); |
| |
| accept(rewritten); |
| return false; |
| } |
| return super.visit(x, ctx); |
| } |
| |
| /** |
| * Handles immediate invocations of JSNI method references. This has to be |
| * done through a wonky method "__gwt_makeJavaInvoke" to handle exceptions |
| * correctly on some browsers. |
| */ |
| @Override |
| public boolean visit(JsInvocation x, JsContext ctx) { |
| if (x.getQualifier() instanceof JsNameRef) { |
| JsNameRef ref = (JsNameRef) x.getQualifier(); |
| String ident = ref.getIdent(); |
| if (ident.startsWith("@")) { |
| int dispId = dispatchInfo.getDispId(ident); |
| |
| Member member; |
| if (dispId < 0) { |
| member = null; |
| } else { |
| member = dispatchInfo.getClassInfoByDispId(dispId).getMember(dispId); |
| } |
| |
| if (member == null) { |
| throw new HostedModeException( |
| "JSNI rewriter found reference to non-existent field in a method invocation: " |
| + ref.getIdent() + " at " + ref.getSourceInfo()); |
| } |
| |
| /* |
| * Make sure the ident is a reference to a method or constructor and |
| * not a reference to a field whose contents (e.g. a Function) we |
| * intend to immediately invoke. |
| * |
| * p.C::method()(); versus p.C::field(); |
| */ |
| if (member instanceof Method || member instanceof Constructor<?>) { |
| |
| // Use a clone instead of modifying the original JSNI |
| // __gwt_makeJavaInvoke(paramCount)(obj, dispId, args) |
| int paramCount = 0; |
| if (member instanceof Method) { |
| paramCount = ((Method) member).getParameterTypes().length; |
| } else if (member instanceof Constructor<?>) { |
| paramCount = ((Constructor<?>) member).getParameterTypes().length; |
| } |
| |
| SourceInfo info = x.getSourceInfo(); |
| JsInvocation inner = new JsInvocation(info, |
| new JsNameRef(info, "__gwt_makeJavaInvoke"), new JsNumberLiteral(info, paramCount)); |
| |
| JsInvocation outer = new JsInvocation(info); |
| outer.setQualifier(inner); |
| JsExpression q = ref.getQualifier(); |
| if (q == null) { |
| q = JsNullLiteral.INSTANCE; |
| } |
| List<JsExpression> arguments = outer.getArguments(); |
| arguments.add(q); |
| arguments.add(new JsNumberLiteral(info, dispId)); |
| arguments.addAll(x.getArguments()); |
| |
| accept(outer); |
| return false; |
| } |
| } |
| } |
| return super.visit(x, ctx); |
| } |
| } |
| |
| /** |
| * Gets the body of a JSNI method, with Java refs escaped for hosted mode |
| * injection. |
| */ |
| public static String getJavaScriptForHostedMode( |
| DispatchIdOracle dispatchInfo, JsniMethod jsniMethod) { |
| JsFunction func = jsniMethod.function(); |
| if (func == null) { |
| return null; |
| } |
| return generateJavaScriptForHostedMode(dispatchInfo, func.getBody()); |
| } |
| |
| /** |
| * Returns a string representing the source output of the JsNode, where all |
| * JSNI idents have been replaced with legal JavaScript for hosted mode. |
| */ |
| private static String generateJavaScriptForHostedMode( |
| DispatchIdOracle dispatchInfo, JsNode node) { |
| DefaultTextOutput out = new DefaultTextOutput(false); |
| JsSourceGenWithJsniIdentFixup vi = new JsSourceGenWithJsniIdentFixup(out, |
| dispatchInfo); |
| vi.accept(node); |
| return out.toString(); |
| } |
| |
| } |