| /* |
| * 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 java.lang.reflect.Constructor; |
| import java.lang.reflect.Field; |
| import java.lang.reflect.Member; |
| import java.lang.reflect.Method; |
| |
| /** |
| * Class for wrapping Java things for JavaScript. |
| */ |
| public class JavaDispatchImpl implements JavaDispatch { |
| |
| private final CompilingClassLoader classLoader; |
| |
| private final Object target; |
| |
| /** |
| * This constructor initializes a dispatcher for handling static members. |
| * |
| * @param ccl class loader to use for dispatching member access |
| */ |
| public JavaDispatchImpl(CompilingClassLoader ccl) { |
| classLoader = ccl; |
| target = null; |
| } |
| |
| /** |
| * This constructor initializes a dispatcher around a particular instance. |
| * |
| * @param ccl class loader to use for dispatching member access |
| * @param target the instance object to use for dispatching member accesses |
| * |
| * @throws NullPointerException if target is null |
| */ |
| public JavaDispatchImpl(CompilingClassLoader ccl, Object target) { |
| if (target == null) { |
| throw new NullPointerException("target cannot be null"); |
| } |
| |
| classLoader = ccl; |
| this.target = target; |
| } |
| |
| /** |
| * @param dispId the unique number of a field |
| * @return the field |
| */ |
| @Override |
| public Field getField(int dispId) { |
| if (dispId < 0) { |
| throw new RuntimeException("Field does not exist."); |
| } |
| Member member = getMember(dispId); |
| |
| if (member instanceof SyntheticClassMember) { |
| try { |
| Field f = SyntheticClassMember.class.getDeclaredField("clazz"); |
| assert f != null; |
| return f; |
| } catch (SecurityException e) { |
| } catch (NoSuchFieldException e) { |
| } |
| assert false : "Should never get here"; |
| } |
| return (Field) member; |
| } |
| |
| /** |
| * @param dispId the unique number of a field |
| * @return true the value of the field |
| * @throws IllegalArgumentException |
| */ |
| @Override |
| public Object getFieldValue(int dispId) { |
| if (dispId < 0) { |
| throw new RuntimeException("Field does not exist."); |
| } |
| |
| Member member = getMember(dispId); |
| |
| if (member instanceof SyntheticClassMember) { |
| return member.getDeclaringClass(); |
| } |
| |
| Field field = (Field) member; |
| try { |
| return field.get(target); |
| } catch (IllegalAccessException e) { |
| // should never, ever happen |
| e.printStackTrace(); |
| throw new RuntimeException(e); |
| } |
| } |
| |
| /** |
| * @param dispId the unique number of a method |
| * @return the method |
| */ |
| @Override |
| public MethodAdaptor getMethod(int dispId) { |
| if (dispId < 0) { |
| throw new RuntimeException("Method does not exist."); |
| } |
| |
| Member m = getMember(dispId); |
| if (m instanceof Method) { |
| return new MethodAdaptor((Method) m); |
| } else if (m instanceof Constructor<?>) { |
| return new MethodAdaptor((Constructor<?>) m); |
| } else { |
| throw new RuntimeException(); |
| } |
| } |
| |
| @Override |
| public Object getTarget() { |
| return target; |
| } |
| |
| /** |
| * @param dispId the unique number of a method or field |
| * @return true if the dispId represents a field |
| */ |
| @Override |
| public boolean isField(int dispId) { |
| if (dispId < 0) { |
| return false; |
| } |
| |
| Member member = getMember(dispId); |
| return member instanceof Field || member instanceof SyntheticClassMember; |
| } |
| |
| /** |
| * @param dispId the unique number of a method or field |
| * @return true if the dispId represents a method |
| */ |
| @Override |
| public boolean isMethod(int dispId) { |
| if (dispId < 0) { |
| return false; |
| } |
| |
| Member m = getMember(dispId); |
| return (m instanceof Method) || (m instanceof Constructor<?>); |
| } |
| |
| /** |
| * @param dispId the unique number of a field |
| * @param value the value to assign to the field |
| * @throws IllegalArgumentException |
| */ |
| @Override |
| public void setFieldValue(int dispId, Object value) { |
| Field field = (Field) getMember(dispId); |
| try { |
| field.set(target, value); |
| } catch (IllegalAccessException e) { |
| // should never, ever happen |
| e.printStackTrace(); |
| throw new RuntimeException(e); |
| } |
| } |
| |
| /** |
| * @param dispId the unique number of a method or field |
| * @return the member |
| */ |
| protected Member getMember(int dispId) { |
| DispatchClassInfo clsInfo = classLoader.getClassInfoByDispId(dispId); |
| return clsInfo.getMember(dispId); |
| } |
| } |