/*
* Copyright 2010 JBoss Inc
*
* Licensed 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.jbpm.designer.web.filter.impl;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import org.jbpm.designer.web.filter.ConfigurableFilterConfig;
import org.jbpm.designer.web.filter.IFilterFactory;
/**
* @author Antoine Toulme
*
* a filter that can delegate to other filters detected via an OSGi declarative service.
*
*/
public class PluggableFilter implements Filter {
private static List<IFilterFactory> _registeredFilters = new ArrayList<IFilterFactory>();
private List<Filter> _filters = new ArrayList<Filter>();
private FilterConfig _filterConfig;
public static void registerFilter(IFilterFactory filter) {
_registeredFilters.add(filter);
}
public void init(FilterConfig filterConfig) throws ServletException {
_filterConfig = filterConfig;
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
if (_filters.size() != _registeredFilters.size()) {
for (Filter f : _filters) {
f.destroy();
}
_filters.clear();
for (IFilterFactory f : _registeredFilters) {
Filter filter = f.createFilter();
ConfigurableFilterConfig config = new ConfigurableFilterConfig(_filterConfig);
f.configureFilterConfig(config);
filter.init(config);
_filters.add(filter);
}
}
new FilterChainImpl(_filters, chain).doFilter(request, response);
if (!response.isCommitted()) {
chain.doFilter(request, response);
}
}
public void destroy() {
for (Filter filter : _filters) {
filter.destroy();
}
_filters.clear();
}
}