Enumeration.java   [plain text]


/* Enumeration.java -- Interface for enumerating lists of objects
   Copyright (C) 1998, 1999, 2001, 2005  Free Software Foundation, Inc.

This file is part of GNU Classpath.

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permission to link this library with independent modules to produce an
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package java.util;

/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
 * "The Java Language Specification", ISBN 0-201-63451-1.
 * Status:  Believed complete and correct
 */

/**
 * Interface for lists of objects that can be returned in sequence. Successive
 * objects are obtained by the nextElement method.
 * <p>
 * As of Java 1.2, the Iterator interface provides the same functionality, but
 * with shorter method names and a new optional method to remove items from the
 * list. If writing for 1.2, consider using Iterator instead. Enumerations over
 * the new collections classes, for use with legacy APIs that require them, can
 * be obtained by the enumeration method in class Collections.
 *
 * @author Warren Levy (warrenl@cygnus.com)
 * @author Eric Blake (ebb9@email.byu.edu)
 * @see Iterator
 * @see Hashtable
 * @see Vector
 * @since 1.0
 * @status updated to 1.4
 */
public interface Enumeration
{
  /**
   * Tests whether there are elements remaining in the enumeration.
   *
   * @return true if there is at least one more element in the enumeration,
   *         that is, if the next call to nextElement will not throw a
   *         NoSuchElementException.
   */
  boolean hasMoreElements();

  /**
   * Obtain the next element in the enumeration.
   *
   * @return the next element in the enumeration
   * @throws NoSuchElementException if there are no more elements
   */
  Object nextElement();
}