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. 014 015 package org.apache.tapestry.binding; 016 017 import org.apache.hivemind.Location; 018 import org.apache.hivemind.util.Defense; 019 import org.apache.tapestry.*; 020 import org.apache.tapestry.coerce.ValueConverter; 021 022 /** 023 * @author Howard M. Lewis Ship 024 * @since 4.0 025 */ 026 public class ListenerMethodBinding extends AbstractBinding implements IActionListener 027 { 028 private final IComponent _component; 029 030 private final String _methodName; 031 032 // We have to defer obtaining the listener until after the page is loaded, because it is 033 // (currently) reliant on the page's engine property to gain access to the 034 // ListenerMapSource. I'd prefer it if this was a final field, resolved by the constructor, 035 // but that will involve injecting the ListenerMapSource into AbstractComponent. 036 037 private IActionListener _listener; 038 039 public ListenerMethodBinding(String description, ValueConverter valueConverter, Location location, 040 IComponent component, String methodName) 041 { 042 super(description, valueConverter, location); 043 044 Defense.notNull(component, "component"); 045 Defense.notNull(methodName, "methodName"); 046 047 _component = component; 048 _methodName = methodName; 049 } 050 051 public Object getComponent() 052 { 053 return _component; 054 } 055 056 /** 057 * Returns this binding object; the binding object delegates to the actual listener. This allows 058 * us to intercept errors and report the location of the binding. 059 */ 060 public Object getObject() 061 { 062 return this; 063 } 064 065 public String getMethodName() 066 { 067 return _methodName; 068 } 069 070 public void actionTriggered(IComponent component, IRequestCycle cycle) 071 { 072 try 073 { 074 if (_listener == null) 075 _listener = _component.getListeners().getListener(_methodName); 076 077 _listener.actionTriggered(component, cycle); 078 } 079 catch (PageRedirectException ex) 080 { 081 throw ex; 082 } 083 catch (RedirectException ex) 084 { 085 throw ex; 086 } 087 catch (RenderRewoundException ex) 088 { 089 throw ex; 090 } 091 catch (RuntimeException ex) 092 { 093 throw new BindingException(BindingMessages.listenerMethodFailure( 094 _component, 095 _methodName, 096 ex), _component, getLocation(), this, ex); 097 } 098 } 099 100 protected void extendDescription(StringBuffer buffer) 101 { 102 buffer.append(", component="); 103 buffer.append(_component.getExtendedId()); 104 buffer.append(", methodName="); 105 buffer.append(_methodName); 106 } 107 }