Initial revision

From-SVN: r102074

libjava/classpath/java/util/Iterator.java

@@ -0,0 +1,87 @@
+/* Iterator.java -- Interface for iterating over collections
+   Copyright (C) 1998, 2001, 2005  Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package java.util;
+
+/**
+ * An object which iterates over a collection. An Iterator is used to return
+ * the items once only, in sequence, by successive calls to the next method.
+ * It is also possible to remove elements from the underlying collection by
+ * using the optional remove method. Iterator is intended as a replacement
+ * for the Enumeration interface of previous versions of Java, which did not
+ * have the remove method and had less conveniently named methods.
+ *
+ * @author Original author unknown
+ * @author Eric Blake (ebb9@email.byu.edu)
+ * @see Collection
+ * @see ListIterator
+ * @see Enumeration
+ * @since 1.2
+ * @status updated to 1.4
+ */
+public interface Iterator
+{
+  /**
+   * Tests whether there are elements remaining in the collection. In other
+   * words, calling <code>next()</code> will not throw an exception.
+   *
+   * @return true if there is at least one more element in the collection
+   */
+  boolean hasNext();
+
+  /**
+   * Obtain the next element in the collection.
+   *
+   * @return the next element in the collection
+   * @throws NoSuchElementException if there are no more elements
+   */
+  Object next();
+
+  /**
+   * Remove from the underlying collection the last element returned by next
+   * (optional operation). This method can be called only once after each
+   * call to <code>next()</code>. It does not affect what will be returned
+   * by subsequent calls to next.
+   *
+   * @throws IllegalStateException if next has not yet been called or remove
+   *         has already been called since the last call to next.
+   * @throws UnsupportedOperationException if this Iterator does not support
+   *         the remove operation.
+   */
+  void remove();
+}