001 package org.apache.myfaces.tobago.event;
002
003 /*
004 * Licensed to the Apache Software Foundation (ASF) under one or more
005 * contributor license agreements. See the NOTICE file distributed with
006 * this work for additional information regarding copyright ownership.
007 * The ASF licenses this file to You under the Apache License, Version 2.0
008 * (the "License"); you may not use this file except in compliance with
009 * the License. You may obtain a copy of the License at
010 *
011 * http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019
020 import org.apache.commons.logging.Log;
021 import org.apache.commons.logging.LogFactory;
022
023 import javax.faces.component.StateHolder;
024 import javax.faces.component.UIComponentBase;
025 import javax.faces.context.FacesContext;
026 import javax.faces.el.ValueBinding;
027
028 /*
029 * Date: Jan 9, 2007
030 * Time: 8:08:01 PM
031 */
032 public class TabChangeListenerValueBindingDelegate implements TabChangeListener, StateHolder {
033 private static final Log LOG = LogFactory.getLog(TabChangeListenerValueBindingDelegate.class);
034 private String type;
035 private ValueBinding valueBinding;
036
037 public TabChangeListenerValueBindingDelegate() {
038 }
039
040 public TabChangeListenerValueBindingDelegate(String type, ValueBinding valueBinding) {
041 this.type = type;
042 this.valueBinding = valueBinding;
043 }
044
045 public void processTabChange(TabChangeEvent tabChangeEvent) {
046 TabChangeListener handler = getTabChangeListener();
047 if (handler != null) {
048 handler.processTabChange(tabChangeEvent);
049 } else {
050 LOG.error("Ignoring TabChangeEvent. No TabChangeListener found.");
051 }
052 }
053
054 public Object saveState(FacesContext context) {
055 Object[] state = new Object[2];
056 state[0] = UIComponentBase.saveAttachedState(context, valueBinding);
057 state[1] = type;
058 return state;
059 }
060
061 public void restoreState(FacesContext context, Object state) {
062 Object[] values = (Object[]) state;
063 valueBinding = (ValueBinding) UIComponentBase.restoreAttachedState(context, values[0]);
064 type = (String) values[1];
065
066 }
067
068 public boolean isTransient() {
069 return false;
070 }
071
072 public void setTransient(boolean newTransientValue) {
073 // ignore
074 }
075
076 private TabChangeListener getTabChangeListener() {
077 TabChangeListener handler = null;
078 if (valueBinding != null) {
079 Object obj = valueBinding.getValue(FacesContext.getCurrentInstance());
080 if (obj != null && obj instanceof TabChangeListener) {
081 handler = (TabChangeListener) obj;
082 }
083 }
084 if (handler == null && type != null) {
085 handler = createTabChangeListener(type);
086 if (handler != null && valueBinding != null) {
087 valueBinding.setValue(FacesContext.getCurrentInstance(), handler);
088 }
089 }
090 return handler;
091 }
092
093 private TabChangeListener createTabChangeListener(String className) {
094 try {
095 Class clazz = getClass().getClassLoader().loadClass(className);
096 return ((TabChangeListener) clazz.newInstance());
097 } catch (Exception e) {
098 LOG.error("", e);
099 }
100 return null;
101 }
102
103 }