/*
* 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.el.unified;
import java.util.Comparator;
import java.util.List;
import javax.el.ELResolver;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import org.apache.myfaces.config.RuntimeConfig;
/**
* Comparator for ELResolvers that shifts the Resolvers from
* the faces-config to the front.
*
* @author Jakob Korherr (latest modification by $Author: jakobk $)
* @version $Revision: 986157 $ $Date: 2010-08-17 01:07:17 +0200 (Tue, 17 Aug 2010) $
*
* @since 1.2.10, 2.0.2
*/
public class CustomFirstELResolverComparator implements Comparator<ELResolver>
{
private List<ELResolver> _facesConfigResolvers;
public int compare(ELResolver r1, ELResolver r2)
{
List<ELResolver> facesConfigResolvers = _getFacesConfigElResolvers();
if (facesConfigResolvers == null)
{
// no el-resolvers in faces-config
return 0; // keep order
}
boolean r1FromFacesConfig = facesConfigResolvers.contains(r1);
boolean r2FromFacesConfig = facesConfigResolvers.contains(r2);
if (r1FromFacesConfig)
{
if (r2FromFacesConfig)
{
// both are from faces-config
return 0; // keep order
}
else
{
// only r1 is from faces-config
return -1;
}
}
else
{
if (r2FromFacesConfig)
{
// only r2 is from faces-config
return 1;
}
else
{
// neither r1 nor r2 are from faces-config
return 0; // keep order
}
}
}
/**
* Returns a List of all ELResolvers from the faces-config.
* @return
*/
private List<ELResolver> _getFacesConfigElResolvers()
{
if (_facesConfigResolvers == null)
{
ExternalContext externalContext
= FacesContext.getCurrentInstance().getExternalContext();
RuntimeConfig runtimeConfig
= RuntimeConfig.getCurrentInstance(externalContext);
_facesConfigResolvers
= runtimeConfig.getFacesConfigElResolvers();
}
return _facesConfigResolvers;
}
}