--- jsr166/src/main/java/util/LinkedList.java	2005/05/17 04:09:23	1.29
+++ jsr166/src/main/java/util/LinkedList.java	2006/05/28 23:36:29	1.45
@@ -1,7 +1,7 @@
 /*
  * %W% %E%
  *
- * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
+ * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
  */
 
@@ -25,18 +25,20 @@ package java.util;
  * list.  Operations that index into the list will traverse the list from
  * the beginning or the end, whichever is closer to the specified index.<p>
  *
- * <b>Note that this implementation is not synchronized.</b> If multiple
- * threads access a list concurrently, and at least one of the threads
- * modifies the list structurally, it <i>must</i> be synchronized
- * externally.  (A structural modification is any operation that adds or
- * deletes one or more elements; merely setting the value of an element is not
- * a structural modification.)  This is typically accomplished by
- * synchronizing on some object that naturally encapsulates the list.  If no
- * such object exists, the list should be "wrapped" using the
- * Collections.synchronizedList method.  This is best done at creation time,
- * to prevent accidental unsynchronized access to the list: <pre>
- *     List list = Collections.synchronizedList(new LinkedList(...));
- * </pre>
+ * <p><strong>Note that this implementation is not synchronized.</strong>
+ * If multiple threads access a linked list concurrently, and at least
+ * one of the threads modifies the list structurally, it <i>must</i> be
+ * synchronized externally.  (A structural modification is any operation
+ * that adds or deletes one or more elements; merely setting the value of
+ * an element is not a structural modification.)  This is typically
+ * accomplished by synchronizing on some object that naturally
+ * encapsulates the list.
+ *
+ * If no such object exists, the list should be "wrapped" using the
+ * {@link Collections#synchronizedList Collections.synchronizedList}
+ * method.  This is best done at creation time, to prevent accidental
+ * unsynchronized access to the list:<pre>
+ *   List list = Collections.synchronizedList(new LinkedList(...));</pre>
  *
  * <p>The iterators returned by this class's <tt>iterator</tt> and
  * <tt>listIterator</tt> methods are <i>fail-fast</i>: if the list is
@@ -57,7 +59,7 @@ package java.util;
  * should be used only to detect bugs.</i>
  *
  * <p>This class is a member of the
- * <a href="{@docRoot}/../guide/collections/index.html">
+ * <a href="{@docRoot}/../technotes/guides/collections/index.html">
  * Java Collections Framework</a>.
  *
  * @author  Josh Bloch
@@ -65,7 +67,6 @@ package java.util;
  * @see	    List
  * @see	    ArrayList
  * @see	    Vector
- * @see	    Collections#synchronizedList(List)
  * @since 1.2
  * @param <E> the type of elements held in this collection
  */
@@ -92,10 +93,10 @@ public class LinkedList<E>
      * @param  c the collection whose elements are to be placed into this list
      * @throws NullPointerException if the specified collection is null
      */
-     public LinkedList(Collection<? extends E> c) {
-	 this();
-	 addAll(c);
-     }
+    public LinkedList(Collection<? extends E> c) {
+	this();
+	addAll(c);
+    }
 
     /**
      * Returns the first element in this list.
@@ -144,19 +145,20 @@ public class LinkedList<E>
     }
 
     /**
-     * Inserts the given element at the beginning of this list.
+     * Inserts the specified element at the beginning of this list.
      *
-     * @param e the element to be inserted at the beginning of this list
+     * @param e the element to add
      */
     public void addFirst(E e) {
 	addBefore(e, header.next);
     }
 
     /**
-     * Appends the given element to the end of this list.  (Identical in
-     * function to the <tt>add</tt> method; included only for consistency.)
+     * Appends the specified element to the end of this list.
      *
-     * @param e the element to be inserted at the end of this list
+     * <p>This method is equivalent to {@link #add}.
+     *
+     * @param e the element to add
      */
     public void addLast(E e) {
 	addBefore(e, header);
@@ -187,8 +189,10 @@ public class LinkedList<E>
     /**
      * Appends the specified element to the end of this list.
      *
+     * <p>This method is equivalent to {@link #addLast}.
+     *
      * @param e element to be appended to this list
-     * @return <tt>true</tt> (as per the spec for {@link Collection#add})
+     * @return <tt>true</tt> (as specified by {@link Collection#add})
      */
     public boolean add(E e) {
 	addBefore(e, header);
@@ -232,10 +236,10 @@ public class LinkedList<E>
      * this list, in the order that they are returned by the specified
      * collection's iterator.  The behavior of this operation is undefined if
      * the specified collection is modified while the operation is in
-     * progress.  (This implies that the behavior of this call is undefined if
-     * the specified Collection is this list, and this list is nonempty.)
+     * progress.  (Note that this will occur if the specified collection is
+     * this list, and it's nonempty.)
      *
-     * @param c the elements to be inserted into this list
+     * @param c collection containing elements to be added to this list
      * @return <tt>true</tt> if this list changed as a result of the call
      * @throws NullPointerException if the specified collection is null
      */
@@ -253,7 +257,7 @@ public class LinkedList<E>
      *
      * @param index index at which to insert the first element
      *              from the specified collection
-     * @param c elements to be inserted into this list
+     * @param c collection containing elements to be added to this list
      * @return <tt>true</tt> if this list changed as a result of the call
      * @throws IndexOutOfBoundsException {@inheritDoc}
      * @throws NullPointerException if the specified collection is null
@@ -481,7 +485,7 @@ public class LinkedList<E>
      * Adds the specified element as the tail (last element) of this list.
      *
      * @param e the element to add
-     * @return <tt>true</tt> (as per the spec for {@link Queue#offer})
+     * @return <tt>true</tt> (as specified by {@link Queue#offer})
      * @since 1.5
      */
     public boolean offer(E e) {
@@ -493,7 +497,7 @@ public class LinkedList<E>
      * Inserts the specified element at the front of this list.
      *
      * @param e the element to insert
-     * @return <tt>true</tt> (as per the spec for {@link Deque#offerFirst})
+     * @return <tt>true</tt> (as specified by {@link Deque#offerFirst})
      * @since 1.6
      */
     public boolean offerFirst(E e) {
@@ -505,7 +509,7 @@ public class LinkedList<E>
      * Inserts the specified element at the end of this list.
      *
      * @param e the element to insert
-     * @return <tt>true</tt> (as per the spec for {@link Deque#offerLast})
+     * @return <tt>true</tt> (as specified by {@link Deque#offerLast})
      * @since 1.6
      */
     public boolean offerLast(E e) {
@@ -542,8 +546,8 @@ public class LinkedList<E>
     }
 
     /**
-     * Retrieves and removes the first element of this list, or
-     * <tt>null</tt> if this list is empty.
+     * Retrieves and removes the first element of this list,
+     * or returns <tt>null</tt> if this list is empty.
      *
      * @return the first element of this list, or <tt>null</tt> if
      *     this list is empty
@@ -556,8 +560,8 @@ public class LinkedList<E>
     }
 
     /**
-     * Retrieves and removes the last element of this list, or
-     * <tt>null</tt> if this list is empty.
+     * Retrieves and removes the last element of this list,
+     * or returns <tt>null</tt> if this list is empty.
      *
      * @return the last element of this list, or <tt>null</tt> if
      *     this list is empty
@@ -621,14 +625,14 @@ public class LinkedList<E>
      */
     public boolean removeLastOccurrence(Object o) {
         if (o==null) {
-            for (Entry e = header.previous; e != header; e = e.previous) {
+            for (Entry<E> e = header.previous; e != header; e = e.previous) {
                 if (e.element==null) {
                     remove(e);
                     return true;
                 }
             }
         } else {
-            for (Entry e = header.previous; e != header; e = e.previous) {
+            for (Entry<E> e = header.previous; e != header; e = e.previous) {
                 if (o.equals(e.element)) {
                     remove(e);
                     return true;
@@ -794,6 +798,27 @@ public class LinkedList<E>
     }
 
     /**
+     * @since 1.6
+     */
+    public Iterator<E> descendingIterator() {
+        return new DescendingIterator();
+    }
+
+    /** Adapter to provide descending iterators via ListItr.previous */
+    private class DescendingIterator implements Iterator {
+        final ListItr itr = new ListItr(size());
+	public boolean hasNext() {
+	    return itr.hasPrevious();
+	}
+	public E next() {
+            return itr.previous();
+        }
+	public void remove() {
+            itr.remove();
+        }
+    }
+
+    /**
      * Returns a shallow copy of this <tt>LinkedList</tt>. (The elements
      * themselves are not cloned.)
      *
@@ -827,7 +852,10 @@ public class LinkedList<E>
      * <p>The returned array will be "safe" in that no references to it are
      * maintained by this list.  (In other words, this method must allocate
      * a new array).  The caller is thus free to modify the returned array.
-     * 
+     *
+     * <p>This method acts as bridge between array-based and collection-based
+     * APIs.
+     *
      * @return an array containing all of the elements in this list
      *         in proper sequence
      */