RELEASE_2_1_13/src/java/org/apache/cocoon/caching/Cacheable.java

/*
 * 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.cocoon.caching;

/**
 * This marker interface declares a (sitemap) component as cacheable.
 * Although this interface is deprecated it is still used for compatibility!
 * 
 * @deprecated by the {@link CacheableProcessingComponent} interface
 * @author <a href="mailto:cziegeler@apache.org">Carsten Ziegeler</a>
 * @version CVS $Id$
 */
public interface Cacheable {

    /**
     * Generate the unique key.
     * This key must be unique inside the space of this component.
     * This method must be invoked before the generateValidity() method.
     *
     * @return The generated key or <code>0</code> if the component
     *              is currently not cacheable.
     */
    long generateKey();

    /**
     * Generate the validity object.
     * Before this method can be invoked the generateKey() method
     * must be invoked.
     *
     * @return The generated validity object or <code>null</code> if the
     *         component is currently not cacheable.
     */
    CacheValidity generateValidity();
}