--- jsr166/src/main/java/util/AbstractQueue.java	2003/07/28 04:11:54	1.6
+++ jsr166/src/main/java/util/AbstractQueue.java	2013/01/16 01:59:47	1.38
@@ -1,31 +1,86 @@
 /*
  * Written by Doug Lea with assistance from members of JCP JSR-166
- * Expert Group and released to the public domain. Use, modify, and
- * redistribute this code in any way without acknowledgement.
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/publicdomain/zero/1.0/
  */
 
 package java.util;
 
 /**
- * AbstractQueue provides default implementations of add, remove, and
- * element based on offer, poll, and peek, respectively but that throw
- * exceptions instead of indicating failure via false or null returns.
- * The provided implementations all assume that the base implementation
- * does <em>not</em> allow <tt>null</tt> elements.
+ * This class provides skeletal implementations of some {@link Queue}
+ * operations. The implementations in this class are appropriate when
+ * the base implementation does <em>not</em> allow {@code null}
+ * elements.  Methods {@link #add add}, {@link #remove remove}, and
+ * {@link #element element} are based on {@link #offer offer}, {@link
+ * #poll poll}, and {@link #peek peek}, respectively, but throw
+ * exceptions instead of indicating failure via {@code false} or
+ * {@code null} returns.
+ *
+ * <p>A {@code Queue} implementation that extends this class must
+ * minimally define a method {@link Queue#offer} which does not permit
+ * insertion of {@code null} elements, along with methods {@link
+ * Queue#peek}, {@link Queue#poll}, {@link Collection#size}, and
+ * {@link Collection#iterator}.  Typically, additional methods will be
+ * overridden as well.  If these requirements cannot be met, consider
+ * instead subclassing {@link AbstractCollection}.
+ *
+ * <p>This class is a member of the
+ * <a href="{@docRoot}/../technotes/guides/collections/index.html">
+ * Java Collections Framework</a>.
+ *
  * @since 1.5
  * @author Doug Lea
+ * @param <E> the type of elements held in this collection
  */
+public abstract class AbstractQueue<E>
+    extends AbstractCollection<E>
+    implements Queue<E> {
+
+    /**
+     * Constructor for use by subclasses.
+     */
+    protected AbstractQueue() {
+    }
 
-public abstract class AbstractQueue<E> extends AbstractCollection<E> implements Queue<E> {
-
-    public boolean add(E x) {
-        if (offer(x))
+    /**
+     * Inserts the specified element into this queue if it is possible to do so
+     * immediately without violating capacity restrictions, returning
+     * {@code true} upon success and throwing an {@code IllegalStateException}
+     * if no space is currently available.
+     *
+     * <p>This implementation returns {@code true} if {@code offer} succeeds,
+     * else throws an {@code IllegalStateException}.
+     *
+     * @param e the element to add
+     * @return {@code true} (as specified by {@link Collection#add})
+     * @throws IllegalStateException if the element cannot be added at this
+     *         time due to capacity restrictions
+     * @throws ClassCastException if the class of the specified element
+     *         prevents it from being added to this queue
+     * @throws NullPointerException if the specified element is null and
+     *         this queue does not permit null elements
+     * @throws IllegalArgumentException if some property of this element
+     *         prevents it from being added to this queue
+     */
+    public boolean add(E e) {
+        if (offer(e))
             return true;
         else
             throw new IllegalStateException("Queue full");
     }
 
-    public E remove() throws NoSuchElementException {
+    /**
+     * Retrieves and removes the head of this queue.  This method differs
+     * from {@link #poll poll} only in that it throws an exception if this
+     * queue is empty.
+     *
+     * <p>This implementation returns the result of {@code poll}
+     * unless the queue is empty.
+     *
+     * @return the head of this queue
+     * @throws NoSuchElementException if this queue is empty
+     */
+    public E remove() {
         E x = poll();
         if (x != null)
             return x;
@@ -33,7 +88,18 @@ public abstract class AbstractQueue<E> e
             throw new NoSuchElementException();
     }
 
-    public E element() throws NoSuchElementException {
+    /**
+     * Retrieves, but does not remove, the head of this queue.  This method
+     * differs from {@link #peek peek} only in that it throws an exception if
+     * this queue is empty.
+     *
+     * <p>This implementation returns the result of {@code peek}
+     * unless the queue is empty.
+     *
+     * @return the head of this queue
+     * @throws NoSuchElementException if this queue is empty
+     */
+    public E element() {
         E x = peek();
         if (x != null)
             return x;
@@ -41,16 +107,57 @@ public abstract class AbstractQueue<E> e
             throw new NoSuchElementException();
     }
 
+    /**
+     * Removes all of the elements from this queue.
+     * The queue will be empty after this call returns.
+     *
+     * <p>This implementation repeatedly invokes {@link #poll poll} until it
+     * returns {@code null}.
+     */
     public void clear() {
         while (poll() != null)
             ;
     }
 
-    // why is this here? Won't Collection declare this itself??? - David
-    public abstract Iterator<E> iterator();
-}
-
-
-
-
+    /**
+     * Adds all of the elements in the specified collection to this
+     * queue.  Attempts to addAll of a queue to itself result in
+     * {@code IllegalArgumentException}. Further, the behavior of
+     * this operation is undefined if the specified collection is
+     * modified while the operation is in progress.
+     *
+     * <p>This implementation iterates over the specified collection,
+     * and adds each element returned by the iterator to this
+     * queue, in turn.  A runtime exception encountered while
+     * trying to add an element (including, in particular, a
+     * {@code null} element) may result in only some of the elements
+     * having been successfully added when the associated exception is
+     * thrown.
+     *
+     * @param c collection containing elements to be added to this queue
+     * @return {@code true} if this queue changed as a result of the call
+     * @throws ClassCastException if the class of an element of the specified
+     *         collection prevents it from being added to this queue
+     * @throws NullPointerException if the specified collection contains a
+     *         null element and this queue does not permit null elements,
+     *         or if the specified collection is null
+     * @throws IllegalArgumentException if some property of an element of the
+     *         specified collection prevents it from being added to this
+     *         queue, or if the specified collection is this queue
+     * @throws IllegalStateException if not all the elements can be added at
+     *         this time due to insertion restrictions
+     * @see #add(Object)
+     */
+    public boolean addAll(Collection<? extends E> c) {
+        if (c == null)
+            throw new NullPointerException();
+        if (c == this)
+            throw new IllegalArgumentException();
+        boolean modified = false;
+        for (E e : c)
+            if (add(e))
+                modified = true;
+        return modified;
+    }
 
+}