001    /* Cloneable.java -- Interface for marking objects cloneable by Object.clone()
002       Copyright (C) 1998, 1999, 2001, 2002, 2005  Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
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014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
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018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package java.lang;
040    
041    /**
042     * This interface should be implemented by classes wishing to
043     * support of override <code>Object.clone()</code>.  The default
044     * behaviour of <code>clone()</code> performs a shallow copy, but
045     * subclasses often change this to perform a deep copy.  Therefore,
046     * it is a good idea to document how deep your clone will go.
047     * If <code>clone()</code> is called on an object which does not
048     * implement this interface, a <code>CloneNotSupportedException</code>
049     * will be thrown.
050     *
051     * <p>This interface is simply a tagging interface; it carries no
052     * requirements on methods to implement.  However, it is typical for
053     * a Cloneable class to implement at least <code>equals</code>,
054     * <code>hashCode</code>, and <code>clone</code>, sometimes
055     * increasing the accessibility of clone to be public. The typical
056     * implementation of <code>clone</code> invokes <code>super.clone()</code>
057     * rather than a constructor, but this is not a requirement.
058     *
059     * <p>If an object that implement Cloneable should not be cloned,
060     * simply override the <code>clone</code> method to throw a
061     * <code>CloneNotSupportedException</code>.
062     *
063     * <p>All array types implement Cloneable, and have a public
064     * <code>clone</code> method that will never fail with a
065     * <code>CloneNotSupportedException</code>.
066     *
067     * @author Paul Fisher
068     * @author Eric Blake (ebb9@email.byu.edu)
069     * @author Warren Levy (warrenl@cygnus.com)
070     * @see Object#clone()
071     * @see CloneNotSupportedException
072     * @since 1.0
073     * @status updated to 1.4
074     */
075    public interface Cloneable
076    {
077      // Tagging interface only.
078    }