151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski/* 251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. 351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This code is free software; you can redistribute it and/or modify it 651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * under the terms of the GNU General Public License version 2 only, as 751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * published by the Free Software Foundation. Oracle designates this 851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * particular file as subject to the "Classpath" exception as provided 951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * by Oracle in the LICENSE file that accompanied this code. 1051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 1151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This code is distributed in the hope that it will be useful, but WITHOUT 1251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * version 2 for more details (a copy is included in the LICENSE file that 1551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * accompanied this code). 1651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 1751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * You should have received a copy of the GNU General Public License version 1851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 2 along with this work; if not, write to the Free Software Foundation, 1951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 2151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * or visit www.oracle.com if you need additional information or have any 2351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * questions. 2451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 2551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 2651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebskipackage java.util; 2751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 2851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski/** 2951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This class provides a skeletal implementation of the <tt>Collection</tt> 3051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * interface, to minimize the effort required to implement this interface. <p> 3151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 3251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * To implement an unmodifiable collection, the programmer needs only to 3351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * extend this class and provide implementations for the <tt>iterator</tt> and 3451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>size</tt> methods. (The iterator returned by the <tt>iterator</tt> 3551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * method must implement <tt>hasNext</tt> and <tt>next</tt>.)<p> 3651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 3751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * To implement a modifiable collection, the programmer must additionally 3851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * override this class's <tt>add</tt> method (which otherwise throws an 3951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>UnsupportedOperationException</tt>), and the iterator returned by the 4051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>iterator</tt> method must additionally implement its <tt>remove</tt> 4151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * method.<p> 4251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 4351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * The programmer should generally provide a void (no argument) and 4451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>Collection</tt> constructor, as per the recommendation in the 4551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>Collection</tt> interface specification.<p> 4651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 4751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * The documentation for each non-abstract method in this class describes its 4851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * implementation in detail. Each of these methods may be overridden if 4951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * the collection being implemented admits a more efficient implementation.<p> 5051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 5151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This class is a member of the 52d2449bb576ad1e3a3877364e5e1ae28625f69e35Yi Kong * <a href="{@docRoot}openjdk-redirect.html?v=8&path=/technotes/guides/collections/index.html"> 5351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Java Collections Framework</a>. 5451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 5551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @author Josh Bloch 5651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @author Neal Gafter 5751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @see Collection 5851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @since 1.2 5951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 6051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 6151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebskipublic abstract class AbstractCollection<E> implements Collection<E> { 6251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 6351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Sole constructor. (For invocation by subclass constructors, typically 6451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * implicit.) 6551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 6651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski protected AbstractCollection() { 6751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 6851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 6951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // Query Operations 7051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 7151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 7251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Returns an iterator over the elements contained in this collection. 7351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 7451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @return an iterator over the elements contained in this collection 7551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 7651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public abstract Iterator<E> iterator(); 7751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 7851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public abstract int size(); 7951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 8051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 8151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 8251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 8351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation returns <tt>size() == 0</tt>. 8451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 8551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean isEmpty() { 8651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return size() == 0; 8751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 8851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 8951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 9051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 9151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 9251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation iterates over the elements in the collection, 9351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * checking each element in turn for equality with the specified element. 9451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 9551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ClassCastException {@inheritDoc} 9651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 9751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 9851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean contains(Object o) { 9951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<E> it = iterator(); 10051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (o==null) { 10151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) 10251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (it.next()==null) 10351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return true; 10451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } else { 10551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) 10651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (o.equals(it.next())) 10751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return true; 10851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 10951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return false; 11051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 11151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 11251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 11351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 11451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 11551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation returns an array containing all the elements 11651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * returned by this collection's iterator, in the same order, stored in 11751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * consecutive elements of the array, starting with index {@code 0}. 11851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * The length of the returned array is equal to the number of elements 11951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * returned by the iterator, even if the size of this collection changes 12051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * during iteration, as might happen if the collection permits 12151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * concurrent modification during iteration. The {@code size} method is 12251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * called only as an optimization hint; the correct result is returned 12351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * even if the iterator returns a different number of elements. 12451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 12551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This method is equivalent to: 12651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 12751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <pre> {@code 12851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * List<E> list = new ArrayList<E>(size()); 12951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * for (E e : this) 13051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * list.add(e); 13151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * return list.toArray(); 13251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * }</pre> 13351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 13451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public Object[] toArray() { 13551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // Estimate size of array; be prepared to see more or fewer elements 13651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Object[] r = new Object[size()]; 13751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<E> it = iterator(); 13851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski for (int i = 0; i < r.length; i++) { 13951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (! it.hasNext()) // fewer elements than expected 14051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return Arrays.copyOf(r, i); 14151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski r[i] = it.next(); 14251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 14351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return it.hasNext() ? finishToArray(r, it) : r; 14451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 14551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 14651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 14751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 14851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 14951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation returns an array containing all the elements 15051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * returned by this collection's iterator in the same order, stored in 15151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * consecutive elements of the array, starting with index {@code 0}. 15251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * If the number of elements returned by the iterator is too large to 15351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * fit into the specified array, then the elements are returned in a 15451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * newly allocated array with length equal to the number of elements 15551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * returned by the iterator, even if the size of this collection 15651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * changes during iteration, as might happen if the collection permits 15751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * concurrent modification during iteration. The {@code size} method is 15851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * called only as an optimization hint; the correct result is returned 15951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * even if the iterator returns a different number of elements. 16051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 16151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This method is equivalent to: 16251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 16351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <pre> {@code 16451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * List<E> list = new ArrayList<E>(size()); 16551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * for (E e : this) 16651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * list.add(e); 16751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * return list.toArray(a); 16851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * }</pre> 16951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 17051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ArrayStoreException {@inheritDoc} 17151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 17251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 17351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public <T> T[] toArray(T[] a) { 17451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // Estimate size of array; be prepared to see more or fewer elements 17551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski int size = size(); 17651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski T[] r = a.length >= size ? a : 17751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski (T[])java.lang.reflect.Array 17851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski .newInstance(a.getClass().getComponentType(), size); 17951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<E> it = iterator(); 18051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 18151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski for (int i = 0; i < r.length; i++) { 18251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (! it.hasNext()) { // fewer elements than expected 18351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (a == r) { 18451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski r[i] = null; // null-terminate 18551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } else if (a.length < i) { 18651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return Arrays.copyOf(r, i); 18751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } else { 18851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski System.arraycopy(r, 0, a, 0, i); 18951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (a.length > i) { 19051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski a[i] = null; 19151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 19251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 19351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return a; 19451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 19551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski r[i] = (T)it.next(); 19651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 19751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // more elements than expected 19851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return it.hasNext() ? finishToArray(r, it) : r; 19951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 20051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 20151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 20251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * The maximum size of array to allocate. 20351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Some VMs reserve some header words in an array. 20451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Attempts to allocate larger arrays may result in 20551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * OutOfMemoryError: Requested array size exceeds VM limit 20651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 20751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; 20851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 20951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 21051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Reallocates the array being used within toArray when the iterator 21151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * returned more elements than expected, and finishes filling it from 21251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * the iterator. 21351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 21451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @param r the array, replete with previously stored elements 21551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @param it the in-progress iterator over this collection 21651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @return array containing the elements in the given array, plus any 21751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * further elements returned by the iterator, trimmed to size 21851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 21951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski private static <T> T[] finishToArray(T[] r, Iterator<?> it) { 22051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski int i = r.length; 22151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) { 22251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski int cap = r.length; 22351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (i == cap) { 22451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski int newCap = cap + (cap >> 1) + 1; 22551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // overflow-conscious code 22651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (newCap - MAX_ARRAY_SIZE > 0) 22751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski newCap = hugeCapacity(cap + 1); 22851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski r = Arrays.copyOf(r, newCap); 22951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 23051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski r[i++] = (T)it.next(); 23151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 23251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // trim if overallocated 23351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return (i == r.length) ? r : Arrays.copyOf(r, i); 23451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 23551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 23651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski private static int hugeCapacity(int minCapacity) { 23751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (minCapacity < 0) // overflow 23851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski throw new OutOfMemoryError 23951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski ("Required array size too large"); 24051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return (minCapacity > MAX_ARRAY_SIZE) ? 24151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Integer.MAX_VALUE : 24251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski MAX_ARRAY_SIZE; 24351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 24451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 24551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // Modification Operations 24651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 24751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 24851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 24951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 25051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation always throws an 25151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>UnsupportedOperationException</tt>. 25251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 25351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws UnsupportedOperationException {@inheritDoc} 25451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ClassCastException {@inheritDoc} 25551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 25651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws IllegalArgumentException {@inheritDoc} 25751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws IllegalStateException {@inheritDoc} 25851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 25951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean add(E e) { 26051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski throw new UnsupportedOperationException(); 26151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 26251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 26351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 26451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 26551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 26651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation iterates over the collection looking for the 26751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * specified element. If it finds the element, it removes the element 26851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * from the collection using the iterator's remove method. 26951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 27051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>Note that this implementation throws an 27151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>UnsupportedOperationException</tt> if the iterator returned by this 27251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * collection's iterator method does not implement the <tt>remove</tt> 27351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * method and this collection contains the specified object. 27451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 27551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws UnsupportedOperationException {@inheritDoc} 27651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ClassCastException {@inheritDoc} 27751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 27851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 27951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean remove(Object o) { 28051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<E> it = iterator(); 28151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (o==null) { 28251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) { 28351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (it.next()==null) { 28451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski it.remove(); 28551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return true; 28651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 28751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 28851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } else { 28951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) { 29051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (o.equals(it.next())) { 29151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski it.remove(); 29251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return true; 29351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 29451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 29551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 29651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return false; 29751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 29851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 29951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 30051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // Bulk Operations 30151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 30251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 30351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 30451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 30551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation iterates over the specified collection, 30651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * checking each element returned by the iterator in turn to see 30751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * if it's contained in this collection. If all elements are so 30851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * contained <tt>true</tt> is returned, otherwise <tt>false</tt>. 30951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 31051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ClassCastException {@inheritDoc} 31151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 31251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @see #contains(Object) 31351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 31451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean containsAll(Collection<?> c) { 31551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski for (Object e : c) 31651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (!contains(e)) 31751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return false; 31851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return true; 31951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 32051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 32151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 32251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 32351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 32451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation iterates over the specified collection, and adds 32551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * each object returned by the iterator to this collection, in turn. 32651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 32751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>Note that this implementation will throw an 32851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>UnsupportedOperationException</tt> unless <tt>add</tt> is 32951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * overridden (assuming the specified collection is non-empty). 33051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 33151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws UnsupportedOperationException {@inheritDoc} 33251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ClassCastException {@inheritDoc} 33351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 33451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws IllegalArgumentException {@inheritDoc} 33551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws IllegalStateException {@inheritDoc} 33651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 33751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @see #add(Object) 33851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 33951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean addAll(Collection<? extends E> c) { 34051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski boolean modified = false; 34151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski for (E e : c) 34251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (add(e)) 34351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski modified = true; 34451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return modified; 34551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 34651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 34751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 34851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 34951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 35051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation iterates over this collection, checking each 35151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * element returned by the iterator in turn to see if it's contained 35251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * in the specified collection. If it's so contained, it's removed from 35351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * this collection with the iterator's <tt>remove</tt> method. 35451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 35551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>Note that this implementation will throw an 35651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>UnsupportedOperationException</tt> if the iterator returned by the 35751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>iterator</tt> method does not implement the <tt>remove</tt> method 35851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * and this collection contains one or more elements in common with the 35951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * specified collection. 36051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 36151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws UnsupportedOperationException {@inheritDoc} 36251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ClassCastException {@inheritDoc} 36351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 36451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 36551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @see #remove(Object) 36651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @see #contains(Object) 36751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 36851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean removeAll(Collection<?> c) { 36951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski boolean modified = false; 37051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<?> it = iterator(); 37151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) { 37251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (c.contains(it.next())) { 37351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski it.remove(); 37451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski modified = true; 37551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 37651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 37751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return modified; 37851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 37951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 38051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 38151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 38251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 38351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation iterates over this collection, checking each 38451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * element returned by the iterator in turn to see if it's contained 38551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * in the specified collection. If it's not so contained, it's removed 38651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * from this collection with the iterator's <tt>remove</tt> method. 38751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 38851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>Note that this implementation will throw an 38951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>UnsupportedOperationException</tt> if the iterator returned by the 39051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>iterator</tt> method does not implement the <tt>remove</tt> method 39151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * and this collection contains one or more elements not present in the 39251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * specified collection. 39351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 39451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws UnsupportedOperationException {@inheritDoc} 39551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws ClassCastException {@inheritDoc} 39651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws NullPointerException {@inheritDoc} 39751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 39851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @see #remove(Object) 39951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @see #contains(Object) 40051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 40151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public boolean retainAll(Collection<?> c) { 40251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski boolean modified = false; 40351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<E> it = iterator(); 40451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) { 40551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (!c.contains(it.next())) { 40651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski it.remove(); 40751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski modified = true; 40851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 40951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 41051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return modified; 41151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 41251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 41351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 41451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * {@inheritDoc} 41551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 41651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>This implementation iterates over this collection, removing each 41751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * element using the <tt>Iterator.remove</tt> operation. Most 41851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * implementations will probably choose to override this method for 41951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * efficiency. 42051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 42151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <p>Note that this implementation will throw an 42251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>UnsupportedOperationException</tt> if the iterator returned by this 42351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * collection's <tt>iterator</tt> method does not implement the 42451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>remove</tt> method and this collection is non-empty. 42551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 42651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @throws UnsupportedOperationException {@inheritDoc} 42751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 42851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public void clear() { 42951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<E> it = iterator(); 43051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski while (it.hasNext()) { 43151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski it.next(); 43251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski it.remove(); 43351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 43451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 43551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 43651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 43751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // String conversion 43851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 43951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 44051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Returns a string representation of this collection. The string 44151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * representation consists of a list of the collection's elements in the 44251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * order they are returned by its iterator, enclosed in square brackets 44351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * (<tt>"[]"</tt>). Adjacent elements are separated by the characters 44451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <tt>", "</tt> (comma and space). Elements are converted to strings as 44551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * by {@link String#valueOf(Object)}. 44651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 44751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @return a string representation of this collection 44851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 44951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public String toString() { 45051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski Iterator<E> it = iterator(); 45151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (! it.hasNext()) 45251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return "[]"; 45351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 45451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski StringBuilder sb = new StringBuilder(); 45551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski sb.append('['); 45651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski for (;;) { 45751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski E e = it.next(); 45851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski sb.append(e == this ? "(this Collection)" : e); 45951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski if (! it.hasNext()) 46051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski return sb.append(']').toString(); 46151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski sb.append(',').append(' '); 46251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 46351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 46451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 46551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski} 466