| // Copyright 2013 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.tapestry5.internal.wro4j; |
| |
| import org.apache.tapestry5.ioc.Resource; |
| import org.apache.tapestry5.ioc.internal.util.CollectionFactory; |
| import org.apache.tapestry5.services.assets.ResourceDependencies; |
| |
| import java.io.IOException; |
| import java.util.Map; |
| |
| /** |
| * Manages a collection of Resources and can check to see if any resource's actual content has changed. |
| * |
| * @since 5.4 |
| */ |
| public class ContentChangeTracker implements ResourceDependencies |
| { |
| private final Map<Resource, Long> checksums = CollectionFactory.newMap(); |
| |
| public void addDependency(Resource dependency) |
| { |
| try |
| { |
| long checksum = ResourceTransformUtils.toChecksum(dependency); |
| |
| checksums.put(dependency, checksum); |
| } catch (IOException e) |
| { |
| throw new RuntimeException(e); |
| } |
| |
| } |
| |
| /** |
| * Checks all resources tracked by this instance and returns true if any resource's content has changed. |
| * |
| * @return true if a change has occurred |
| */ |
| public boolean changes() throws IOException |
| { |
| for (Map.Entry<Resource, Long> e : checksums.entrySet()) |
| { |
| long current = ResourceTransformUtils.toChecksum(e.getKey()); |
| |
| if (current != e.getValue().longValue()) |
| { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| |
| } |