1/* 2 * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23import java.util.HashSet; 24import java.util.AbstractSet; 25import java.util.Collection; 26import java.util.Iterator; 27import java.util.Set; 28import java.util.function.Supplier; 29 30/** 31 * @library 32 * 33 * A simple mutable set implementation that provides only default 34 * implementations of all methods. ie. none of the Set interface default methods 35 * have overridden implementations. 36 * 37 * @param <E> type of set members 38 */ 39public class ExtendsAbstractSet<E> extends AbstractSet<E> { 40 41 protected final Set<E> set; 42 43 public ExtendsAbstractSet() { 44 this(HashSet<E>::new); 45 } 46 47 public ExtendsAbstractSet(Collection<E> source) { 48 this(); 49 addAll(source); 50 } 51 52 protected ExtendsAbstractSet(Supplier<Set<E>> backer) { 53 this.set = backer.get(); 54 } 55 56 public boolean add(E element) { 57 return set.add(element); 58 } 59 60 public boolean remove(Object element) { 61 return set.remove(element); 62 } 63 64 public Iterator<E> iterator() { 65 return new Iterator<E>() { 66 Iterator<E> source = set.iterator(); 67 68 public boolean hasNext() { 69 return source.hasNext(); 70 } 71 72 public E next() { 73 return source.next(); 74 } 75 76 public void remove() { 77 source.remove(); 78 } 79 }; 80 } 81 82 public int size() { 83 return set.size(); 84 } 85} 86