| /* |
| * 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.tools.ant.types.resources; |
| |
| import java.util.List; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| |
| import org.apache.tools.ant.BuildException; |
| import org.apache.tools.ant.types.ResourceCollection; |
| |
| /** |
| * ResourceCollection representing the difference between |
| * two or more nested ResourceCollections. |
| * @since Ant 1.7 |
| */ |
| public class Difference extends BaseResourceCollectionContainer { |
| |
| /** |
| * Calculate the difference of the nested ResourceCollections. |
| * @return a Collection of Resources. |
| */ |
| protected Collection getCollection() { |
| List rc = getResourceCollections(); |
| int size = rc.size(); |
| if (size < 2) { |
| throw new BuildException("The difference of " + size |
| + " resource collection" + ((size == 1) ? "" : "s") |
| + " is undefined."); |
| } |
| HashSet hs = new HashSet(); |
| ArrayList al = new ArrayList(); |
| for (Iterator rcIter = rc.iterator(); rcIter.hasNext();) { |
| for (Iterator r = nextRC(rcIter).iterator(); r.hasNext();) { |
| Object next = r.next(); |
| if (hs.add(next)) { |
| al.add(next); |
| } else { |
| al.remove(next); |
| } |
| } |
| } |
| return al; |
| } |
| |
| private static ResourceCollection nextRC(Iterator i) { |
| return (ResourceCollection) i.next(); |
| } |
| |
| } |