non-releases/trunk_before_flattening/src/java/org/apache/cocoon/acting/ClearCacheAction.java

/*
 * Copyright 1999-2004 The Apache Software Foundation.
 * 
 * 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.apache.cocoon.acting;

import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.thread.ThreadSafe;
import org.apache.cocoon.caching.Cache;
import org.apache.cocoon.environment.Redirector;
import org.apache.cocoon.environment.SourceResolver;

import java.util.Map;

/**
 * Simple action which ensures the cache is cleared of all
 * cached results
 *
 * @version $Id$
 */
public class ClearCacheAction extends ServiceableAction implements ThreadSafe {

    public Map act(Redirector redirector,
                    SourceResolver resolver,
                    Map objectModel,
                    String src,
                    Parameters par
    ) throws Exception {
        final String cacheRole = par.getParameter("cache-role", Cache.ROLE);
        Cache cache = null;

        try {
            cache = (Cache)this.manager.lookup(cacheRole);
            cache.clear();
            return EMPTY_MAP;
        } catch (Exception ex) {
	        if (this.getLogger().isDebugEnabled()) {
                getLogger().debug("Exception while trying to clear Cache with role " + cacheRole, ex);
            }
            return null;
        } finally {
            this.manager.release( cache );
        }
    }
}