| /* |
| * Copyright 2000-2014 JetBrains s.r.o. |
| * |
| * 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.intellij.util; |
| |
| import com.intellij.openapi.Disposable; |
| import com.intellij.openapi.diagnostic.Logger; |
| import com.intellij.openapi.util.Disposer; |
| import com.intellij.util.containers.ContainerUtil; |
| import org.jetbrains.annotations.NonNls; |
| import org.jetbrains.annotations.NotNull; |
| |
| import java.lang.reflect.InvocationHandler; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Proxy; |
| import java.util.EventListener; |
| import java.util.List; |
| |
| /** |
| * @author max |
| */ |
| public class EventDispatcher<T extends EventListener> { |
| private static final Logger LOG = Logger.getInstance("#com.intellij.util.EventDispatcher"); |
| |
| private final T myMulticaster; |
| |
| private final List<T> myListeners = ContainerUtil.createLockFreeCopyOnWriteList(); |
| |
| public static <T extends EventListener> EventDispatcher<T> create(@NotNull Class<T> listenerClass) { |
| return new EventDispatcher<T>(listenerClass); |
| } |
| |
| private EventDispatcher(@NotNull Class<T> listenerClass) { |
| LOG.assertTrue(listenerClass.isInterface(), "listenerClass must be an interface"); |
| InvocationHandler handler = new InvocationHandler() { |
| @Override |
| @NonNls |
| public Object invoke(Object proxy, final Method method, final Object[] args) throws Throwable { |
| if (method.getDeclaringClass().getName().equals("java.lang.Object")) { |
| @NonNls String methodName = method.getName(); |
| if (methodName.equals("toString")) { |
| return "Multicaster"; |
| } |
| else if (methodName.equals("hashCode")) { |
| return Integer.valueOf(System.identityHashCode(proxy)); |
| } |
| else if (methodName.equals("equals")) { |
| return proxy == args[0] ? Boolean.TRUE : Boolean.FALSE; |
| } |
| else { |
| LOG.error("Incorrect Object's method invoked for proxy:" + methodName); |
| return null; |
| } |
| } |
| else { |
| dispatch(method, args); |
| return null; |
| } |
| } |
| }; |
| |
| //noinspection unchecked |
| myMulticaster = (T)Proxy.newProxyInstance(listenerClass.getClassLoader(), new Class[]{listenerClass}, handler); |
| } |
| |
| @NotNull |
| public T getMulticaster() { |
| return myMulticaster; |
| } |
| |
| private void dispatch(@NotNull Method method, Object[] args) { |
| method.setAccessible(true); |
| |
| for (T listener : myListeners) { |
| try { |
| method.invoke(listener, args); |
| } |
| catch (AbstractMethodError ignored) { |
| // Do nothing. This listener just does not implement something newly added yet. |
| // AbstractMethodError is normally wrapped in InvocationTargetException, |
| // but some Java versions didn't do it in some cases (see http://bugs.java.com/bugdatabase/view_bug.do?bug_id=6531596) |
| } |
| catch (RuntimeException e) { |
| throw e; |
| } |
| catch (Exception e) { |
| final Throwable cause = e.getCause(); |
| if (cause instanceof RuntimeException) { |
| throw (RuntimeException)cause; |
| } |
| else if (!(cause instanceof AbstractMethodError)) { // AbstractMethodError means this listener doesn't implement some new method in interface |
| LOG.error(cause); |
| } |
| } |
| } |
| } |
| |
| public void addListener(@NotNull T listener) { |
| myListeners.add(listener); |
| } |
| |
| public void addListener(@NotNull final T listener, @NotNull Disposable parentDisposable) { |
| addListener(listener); |
| Disposer.register(parentDisposable, new Disposable() { |
| @Override |
| public void dispose() { |
| removeListener(listener); |
| } |
| }); |
| } |
| |
| public void removeListener(@NotNull T listener) { |
| myListeners.remove(listener); |
| } |
| |
| public boolean hasListeners() { |
| return !myListeners.isEmpty(); |
| } |
| |
| @NotNull |
| public List<T> getListeners() { |
| return myListeners; |
| } |
| } |