1.1 --- a/emul/compact/src/main/java/java/util/AbstractQueue.java Fri Mar 22 16:59:47 2013 +0100
1.2 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000
1.3 @@ -1,192 +0,0 @@
1.4 -/*
1.5 - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.6 - *
1.7 - * This code is free software; you can redistribute it and/or modify it
1.8 - * under the terms of the GNU General Public License version 2 only, as
1.9 - * published by the Free Software Foundation. Oracle designates this
1.10 - * particular file as subject to the "Classpath" exception as provided
1.11 - * by Oracle in the LICENSE file that accompanied this code.
1.12 - *
1.13 - * This code is distributed in the hope that it will be useful, but WITHOUT
1.14 - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.15 - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.16 - * version 2 for more details (a copy is included in the LICENSE file that
1.17 - * accompanied this code).
1.18 - *
1.19 - * You should have received a copy of the GNU General Public License version
1.20 - * 2 along with this work; if not, write to the Free Software Foundation,
1.21 - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.22 - *
1.23 - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.24 - * or visit www.oracle.com if you need additional information or have any
1.25 - * questions.
1.26 - */
1.27 -
1.28 -/*
1.29 - * This file is available under and governed by the GNU General Public
1.30 - * License version 2 only, as published by the Free Software Foundation.
1.31 - * However, the following notice accompanied the original version of this
1.32 - * file:
1.33 - *
1.34 - * Written by Doug Lea with assistance from members of JCP JSR-166
1.35 - * Expert Group and released to the public domain, as explained at
1.36 - * http://creativecommons.org/publicdomain/zero/1.0/
1.37 - */
1.38 -
1.39 -package java.util;
1.40 -
1.41 -/**
1.42 - * This class provides skeletal implementations of some {@link Queue}
1.43 - * operations. The implementations in this class are appropriate when
1.44 - * the base implementation does <em>not</em> allow <tt>null</tt>
1.45 - * elements. Methods {@link #add add}, {@link #remove remove}, and
1.46 - * {@link #element element} are based on {@link #offer offer}, {@link
1.47 - * #poll poll}, and {@link #peek peek}, respectively, but throw
1.48 - * exceptions instead of indicating failure via <tt>false</tt> or
1.49 - * <tt>null</tt> returns.
1.50 - *
1.51 - * <p>A <tt>Queue</tt> implementation that extends this class must
1.52 - * minimally define a method {@link Queue#offer} which does not permit
1.53 - * insertion of <tt>null</tt> elements, along with methods {@link
1.54 - * Queue#peek}, {@link Queue#poll}, {@link Collection#size}, and
1.55 - * {@link Collection#iterator}. Typically, additional methods will be
1.56 - * overridden as well. If these requirements cannot be met, consider
1.57 - * instead subclassing {@link AbstractCollection}.
1.58 - *
1.59 - * <p>This class is a member of the
1.60 - * <a href="{@docRoot}/../technotes/guides/collections/index.html">
1.61 - * Java Collections Framework</a>.
1.62 - *
1.63 - * @since 1.5
1.64 - * @author Doug Lea
1.65 - * @param <E> the type of elements held in this collection
1.66 - */
1.67 -public abstract class AbstractQueue<E>
1.68 - extends AbstractCollection<E>
1.69 - implements Queue<E> {
1.70 -
1.71 - /**
1.72 - * Constructor for use by subclasses.
1.73 - */
1.74 - protected AbstractQueue() {
1.75 - }
1.76 -
1.77 - /**
1.78 - * Inserts the specified element into this queue if it is possible to do so
1.79 - * immediately without violating capacity restrictions, returning
1.80 - * <tt>true</tt> upon success and throwing an <tt>IllegalStateException</tt>
1.81 - * if no space is currently available.
1.82 - *
1.83 - * <p>This implementation returns <tt>true</tt> if <tt>offer</tt> succeeds,
1.84 - * else throws an <tt>IllegalStateException</tt>.
1.85 - *
1.86 - * @param e the element to add
1.87 - * @return <tt>true</tt> (as specified by {@link Collection#add})
1.88 - * @throws IllegalStateException if the element cannot be added at this
1.89 - * time due to capacity restrictions
1.90 - * @throws ClassCastException if the class of the specified element
1.91 - * prevents it from being added to this queue
1.92 - * @throws NullPointerException if the specified element is null and
1.93 - * this queue does not permit null elements
1.94 - * @throws IllegalArgumentException if some property of this element
1.95 - * prevents it from being added to this queue
1.96 - */
1.97 - public boolean add(E e) {
1.98 - if (offer(e))
1.99 - return true;
1.100 - else
1.101 - throw new IllegalStateException("Queue full");
1.102 - }
1.103 -
1.104 - /**
1.105 - * Retrieves and removes the head of this queue. This method differs
1.106 - * from {@link #poll poll} only in that it throws an exception if this
1.107 - * queue is empty.
1.108 - *
1.109 - * <p>This implementation returns the result of <tt>poll</tt>
1.110 - * unless the queue is empty.
1.111 - *
1.112 - * @return the head of this queue
1.113 - * @throws NoSuchElementException if this queue is empty
1.114 - */
1.115 - public E remove() {
1.116 - E x = poll();
1.117 - if (x != null)
1.118 - return x;
1.119 - else
1.120 - throw new NoSuchElementException();
1.121 - }
1.122 -
1.123 - /**
1.124 - * Retrieves, but does not remove, the head of this queue. This method
1.125 - * differs from {@link #peek peek} only in that it throws an exception if
1.126 - * this queue is empty.
1.127 - *
1.128 - * <p>This implementation returns the result of <tt>peek</tt>
1.129 - * unless the queue is empty.
1.130 - *
1.131 - * @return the head of this queue
1.132 - * @throws NoSuchElementException if this queue is empty
1.133 - */
1.134 - public E element() {
1.135 - E x = peek();
1.136 - if (x != null)
1.137 - return x;
1.138 - else
1.139 - throw new NoSuchElementException();
1.140 - }
1.141 -
1.142 - /**
1.143 - * Removes all of the elements from this queue.
1.144 - * The queue will be empty after this call returns.
1.145 - *
1.146 - * <p>This implementation repeatedly invokes {@link #poll poll} until it
1.147 - * returns <tt>null</tt>.
1.148 - */
1.149 - public void clear() {
1.150 - while (poll() != null)
1.151 - ;
1.152 - }
1.153 -
1.154 - /**
1.155 - * Adds all of the elements in the specified collection to this
1.156 - * queue. Attempts to addAll of a queue to itself result in
1.157 - * <tt>IllegalArgumentException</tt>. Further, the behavior of
1.158 - * this operation is undefined if the specified collection is
1.159 - * modified while the operation is in progress.
1.160 - *
1.161 - * <p>This implementation iterates over the specified collection,
1.162 - * and adds each element returned by the iterator to this
1.163 - * queue, in turn. A runtime exception encountered while
1.164 - * trying to add an element (including, in particular, a
1.165 - * <tt>null</tt> element) may result in only some of the elements
1.166 - * having been successfully added when the associated exception is
1.167 - * thrown.
1.168 - *
1.169 - * @param c collection containing elements to be added to this queue
1.170 - * @return <tt>true</tt> if this queue changed as a result of the call
1.171 - * @throws ClassCastException if the class of an element of the specified
1.172 - * collection prevents it from being added to this queue
1.173 - * @throws NullPointerException if the specified collection contains a
1.174 - * null element and this queue does not permit null elements,
1.175 - * or if the specified collection is null
1.176 - * @throws IllegalArgumentException if some property of an element of the
1.177 - * specified collection prevents it from being added to this
1.178 - * queue, or if the specified collection is this queue
1.179 - * @throws IllegalStateException if not all the elements can be added at
1.180 - * this time due to insertion restrictions
1.181 - * @see #add(Object)
1.182 - */
1.183 - public boolean addAll(Collection<? extends E> c) {
1.184 - if (c == null)
1.185 - throw new NullPointerException();
1.186 - if (c == this)
1.187 - throw new IllegalArgumentException();
1.188 - boolean modified = false;
1.189 - for (E e : c)
1.190 - if (add(e))
1.191 - modified = true;
1.192 - return modified;
1.193 - }
1.194 -
1.195 -}