/*
* 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.wicket.request.resource.caching.version;
import java.util.regex.Pattern;
import org.apache.wicket.request.resource.caching.IStaticCacheableResource;
/**
* Provides a version string for a cacheable resource specified by {@link org.apache.wicket.request.resource.caching.IStaticCacheableResource}
* <p/>
* the version string will be used as a distinguishing mark when rendering resources
*
* @see org.apache.wicket.request.resource.caching.QueryStringWithVersionResourceCachingStrategy
* @see org.apache.wicket.request.resource.caching.FilenameWithVersionResourceCachingStrategy
*
* @author Peter Ertl
*
* @since 1.5
*/
public interface IResourceVersion
{
/**
* get unique string identifying the version of the resource
*
* @param resource
* cacheable resource
* @return unique version string or <code>null</code>
* if version string could not be calculated
*/
String getVersion(IStaticCacheableResource resource);
/**
* a pattern that matches returned versions
*
* @return a pattern or <code>null</code> if no pattern
* is available
*/
Pattern getVersionPattern();
}