Java tutorial
//package com.java2s; /* * Copyright 1999-2004 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. */ import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; public class Main { /** * Returns a {@link Collection} containing <tt><i>a</i> - <i>b</i></tt>. The * cardinality of each element <i>e</i> in the returned {@link Collection} * will be the cardinality of <i>e</i> in <i>a</i> minus the cardinality of * <i>e</i> in <i>b</i>, or zero, whichever is greater. * * @see Collection#removeAll */ public static Collection subtract(final Collection a, final Collection b) { ArrayList list = new ArrayList(a); Iterator it = b.iterator(); while (it.hasNext()) { list.remove(it.next()); } return list; } }