--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/util/ListIterator.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,195 @@
+/*
+ * Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.util;
+
+/**
+ * An iterator for lists that allows the programmer
+ * to traverse the list in either direction, modify
+ * the list during iteration, and obtain the iterator's
+ * current position in the list. A {@code ListIterator}
+ * has no current element; its <I>cursor position</I> always
+ * lies between the element that would be returned by a call
+ * to {@code previous()} and the element that would be
+ * returned by a call to {@code next()}.
+ * An iterator for a list of length {@code n} has {@code n+1} possible
+ * cursor positions, as illustrated by the carets ({@code ^}) below:
+ * <PRE>
+ * Element(0) Element(1) Element(2) ... Element(n-1)
+ * cursor positions: ^ ^ ^ ^ ^
+ * </PRE>
+ * Note that the {@link #remove} and {@link #set(Object)} methods are
+ * <i>not</i> defined in terms of the cursor position; they are defined to
+ * operate on the last element returned by a call to {@link #next} or
+ * {@link #previous()}.
+ *
+ * <p>This interface is a member of the
+ * <a href="{@docRoot}/../technotes/guides/collections/index.html">
+ * Java Collections Framework</a>.
+ *
+ * @author Josh Bloch
+ * @see Collection
+ * @see List
+ * @see Iterator
+ * @see Enumeration
+ * @see List#listIterator()
+ * @since 1.2
+ */
+public interface ListIterator<E> extends Iterator<E> {
+ // Query Operations
+
+ /**
+ * Returns {@code true} if this list iterator has more elements when
+ * traversing the list in the forward direction. (In other words,
+ * returns {@code true} if {@link #next} would return an element rather
+ * than throwing an exception.)
+ *
+ * @return {@code true} if the list iterator has more elements when
+ * traversing the list in the forward direction
+ */
+ boolean hasNext();
+
+ /**
+ * Returns the next element in the list and advances the cursor position.
+ * This method may be called repeatedly to iterate through the list,
+ * or intermixed with calls to {@link #previous} to go back and forth.
+ * (Note that alternating calls to {@code next} and {@code previous}
+ * will return the same element repeatedly.)
+ *
+ * @return the next element in the list
+ * @throws NoSuchElementException if the iteration has no next element
+ */
+ E next();
+
+ /**
+ * Returns {@code true} if this list iterator has more elements when
+ * traversing the list in the reverse direction. (In other words,
+ * returns {@code true} if {@link #previous} would return an element
+ * rather than throwing an exception.)
+ *
+ * @return {@code true} if the list iterator has more elements when
+ * traversing the list in the reverse direction
+ */
+ boolean hasPrevious();
+
+ /**
+ * Returns the previous element in the list and moves the cursor
+ * position backwards. This method may be called repeatedly to
+ * iterate through the list backwards, or intermixed with calls to
+ * {@link #next} to go back and forth. (Note that alternating calls
+ * to {@code next} and {@code previous} will return the same
+ * element repeatedly.)
+ *
+ * @return the previous element in the list
+ * @throws NoSuchElementException if the iteration has no previous
+ * element
+ */
+ E previous();
+
+ /**
+ * Returns the index of the element that would be returned by a
+ * subsequent call to {@link #next}. (Returns list size if the list
+ * iterator is at the end of the list.)
+ *
+ * @return the index of the element that would be returned by a
+ * subsequent call to {@code next}, or list size if the list
+ * iterator is at the end of the list
+ */
+ int nextIndex();
+
+ /**
+ * Returns the index of the element that would be returned by a
+ * subsequent call to {@link #previous}. (Returns -1 if the list
+ * iterator is at the beginning of the list.)
+ *
+ * @return the index of the element that would be returned by a
+ * subsequent call to {@code previous}, or -1 if the list
+ * iterator is at the beginning of the list
+ */
+ int previousIndex();
+
+
+ // Modification Operations
+
+ /**
+ * Removes from the list the last element that was returned by {@link
+ * #next} or {@link #previous} (optional operation). This call can
+ * only be made once per call to {@code next} or {@code previous}.
+ * It can be made only if {@link #add} has not been
+ * called after the last call to {@code next} or {@code previous}.
+ *
+ * @throws UnsupportedOperationException if the {@code remove}
+ * operation is not supported by this list iterator
+ * @throws IllegalStateException if neither {@code next} nor
+ * {@code previous} have been called, or {@code remove} or
+ * {@code add} have been called after the last call to
+ * {@code next} or {@code previous}
+ */
+ void remove();
+
+ /**
+ * Replaces the last element returned by {@link #next} or
+ * {@link #previous} with the specified element (optional operation).
+ * This call can be made only if neither {@link #remove} nor {@link
+ * #add} have been called after the last call to {@code next} or
+ * {@code previous}.
+ *
+ * @param e the element with which to replace the last element returned by
+ * {@code next} or {@code previous}
+ * @throws UnsupportedOperationException if the {@code set} operation
+ * is not supported by this list iterator
+ * @throws ClassCastException if the class of the specified element
+ * prevents it from being added to this list
+ * @throws IllegalArgumentException if some aspect of the specified
+ * element prevents it from being added to this list
+ * @throws IllegalStateException if neither {@code next} nor
+ * {@code previous} have been called, or {@code remove} or
+ * {@code add} have been called after the last call to
+ * {@code next} or {@code previous}
+ */
+ void set(E e);
+
+ /**
+ * Inserts the specified element into the list (optional operation).
+ * The element is inserted immediately before the next element that
+ * would be returned by {@link #next}, if any, and after the next
+ * element that would be returned by {@link #previous}, if any. (If the
+ * list contains no elements, the new element becomes the sole element
+ * on the list.) The new element is inserted before the implicit
+ * cursor: a subsequent call to {@code next} would be unaffected, and a
+ * subsequent call to {@code previous} would return the new element.
+ * (This call increases by one the value that would be returned by a
+ * call to {@code nextIndex} or {@code previousIndex}.)
+ *
+ * @param e the element to insert
+ * @throws UnsupportedOperationException if the {@code add} method is
+ * not supported by this list iterator
+ * @throws ClassCastException if the class of the specified element
+ * prevents it from being added to this list
+ * @throws IllegalArgumentException if some aspect of this element
+ * prevents it from being added to this list
+ */
+ void add(E e);
+}