001// Copyright 2004, 2005 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.hivemind.lib.impl; 016 017import java.util.ArrayList; 018import java.util.List; 019 020import org.apache.hivemind.ApplicationRuntimeException; 021import org.apache.hivemind.lib.RemoteExceptionCoordinator; 022import org.apache.hivemind.lib.RemoteExceptionEvent; 023import org.apache.hivemind.lib.RemoteExceptionListener; 024 025/** 026 * Core implementation of {@link org.apache.hivemind.lib.RemoteExceptionCoordinator}. 027 * 028 * @author Howard Lewis Ship 029 */ 030 031public class RemoteExceptionCoordinatorImpl implements RemoteExceptionCoordinator 032{ 033 private boolean _locked; 034 private List _listeners; 035 036 private void checkLocked(String methodName) 037 { 038 if (_locked) 039 throw new ApplicationRuntimeException(ImplMessages.coordinatorLocked(methodName)); 040 } 041 042 public synchronized void addRemoteExceptionListener(RemoteExceptionListener listener) 043 { 044 checkLocked("addRemoteExceptionListener"); 045 046 if (_listeners == null) 047 _listeners = new ArrayList(); 048 049 _listeners.add(listener); 050 } 051 052 public synchronized void removeRemoteExceptionListener(RemoteExceptionListener listener) 053 { 054 checkLocked("removeRemoteExceptionListener"); 055 056 if (_listeners == null) 057 return; 058 059 _listeners.remove(listener); 060 } 061 062 public synchronized void fireRemoteExceptionDidOccur(Object source, Throwable exception) 063 { 064 checkLocked("sendNotification"); 065 066 if (_listeners == null || _listeners.size() == 0) 067 return; 068 069 RemoteExceptionEvent event = new RemoteExceptionEvent(source, exception); 070 071 int count = _listeners.size(); 072 073 _locked = true; 074 075 try 076 { 077 078 for (int i = 0; i < count; i++) 079 { 080 RemoteExceptionListener listener = (RemoteExceptionListener) _listeners.get(i); 081 082 listener.remoteExceptionDidOccur(event); 083 } 084 } 085 finally 086 { 087 _locked = false; 088 } 089 090 } 091 092}