/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.myfaces.taglib.core;
import javax.el.ELException;
import javax.el.ValueExpression;
import javax.faces.FacesException;
import javax.faces.component.StateHolder;
import javax.faces.context.FacesContext;
import javax.faces.event.AbortProcessingException;
import javax.faces.event.ActionEvent;
import javax.faces.event.ActionListener;
import org.apache.myfaces.shared.util.ClassUtils;
/**
* This class is used in conjunction with ActionListenerTag.
*
* When a tag like this is in a jsp page:
*
* <f:actionListener binding="#{mybean}"/>
*
* or
*
* <f:actionListener type="#{'anyid'}" binding="#{mybean}"/>
*
* The value of mybean could be already on the context, so this
* converter avoid creating a new variable and use the previous one.
*
* @author Leonardo Uribe (latest modification by $Author: lu4242 $)
* @version $Revision: 1151650 $ $Date: 2011-07-28 00:14:17 +0200 (Thu, 28 Jul 2011) $
*/
public class DelegateActionListener implements ActionListener, StateHolder
{
private ValueExpression _type;
private ValueExpression _binding;
public DelegateActionListener()
{
}
public DelegateActionListener(ValueExpression type, ValueExpression binding)
{
super();
_type = type;
_binding = binding;
}
public boolean isTransient()
{
return false;
}
public void restoreState(FacesContext facesContext, Object state)
{
Object[] values = (Object[]) state;
_type = (ValueExpression) values[0];
_binding = (ValueExpression) values[1];
}
public Object saveState(FacesContext facesContext)
{
Object[] values = new Object[2];
values[0] = _type;
values[1] = _binding;
return values;
}
public void setTransient(boolean arg0)
{
// Do nothing
}
private ActionListener _getDelegate()
{
return _createActionListener();
}
private ActionListener _createActionListener()
{
FacesContext facesContext = FacesContext.getCurrentInstance();
ActionListener listener = null;
// type and/or binding must be specified
try
{
if (null != _binding)
{
try
{
listener = (ActionListener) _binding.getValue(facesContext
.getELContext());
if (null != listener)
{
return listener;
}
}
catch (ELException e)
{
throw new ELException("Exception while evaluating the binding attribute", e);
}
}
if (null != _type)
{
String className;
if (_type.isLiteralText())
{
className = _type.getExpressionString();
}
else
{
className = (String) _type.getValue(facesContext
.getELContext());
}
listener = (ActionListener) ClassUtils.newInstance(className);
if (null != _binding)
{
try
{
_binding
.setValue(facesContext.getELContext(), listener);
}
catch (ELException e)
{
throw new ELException("Exception while evaluating the binding attribute ");
}
}
return listener;
}
}
catch (ClassCastException e)
{
throw new FacesException(e);
}
return listener;
}
public void processAction(ActionEvent event)
throws AbortProcessingException
{
_getDelegate().processAction(event);
}
}