| // Copyright 2004, 2005 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.tapestry.asset; |
| |
| import java.net.URL; |
| |
| /** |
| * Calculates the checksum value, as a string, for a particular classpath resource. This is primarily |
| * used by the {@link org.apache.tapestry.asset.AssetService} to authenticate requests (you are not |
| * allowed access to a resource unless you can provide the correct checksum value). |
| * |
| * This code is based on code from Howard Lewis Ship from the upcoming 3.1 release. |
| * |
| * @author Paul Ferraro |
| * @since 3.0.3 |
| */ |
| public interface ResourceChecksumSource |
| { |
| /** |
| * Returns the checksum value for the given resource. |
| * @param resourceURL the url of a resource |
| * @return the checksum value of the specified resource |
| */ |
| public String getChecksum(URL resourceURL); |
| |
| /** |
| * Clears the internal cache. |
| */ |
| public void reset(); |
| } |