/*
* STANDARD ML OF NEW JERSEY COPYRIGHT NOTICE, LICENSE AND DISCLAIMER.
*
* Copyright (c) 1989-1998 by Lucent Technologies
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose and without fee is hereby granted, provided
* that the above copyright notice appear in all copies and that both the
* copyright notice and this permission notice and warranty disclaimer appear
* in supporting documentation, and that the name of Lucent Technologies, Bell
* Labs or any Lucent entity not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior permission.
*
* Lucent disclaims all warranties with regard to this software, including all
* implied warranties of merchantability and fitness. In no event shall Lucent
* be liable for any special, indirect or consequential damages or any damages
* whatsoever resulting from loss of use, data or profits, whether in an action
* of contract, negligence or other tortious action, arising out of or in
* connection with the use or performance of this software.
*
* Taken from this URL:
* http://www.smlnj.org/license.html
*
* This license is compatible with the GNU GPL (see section "Standard ML of New
* Jersey Copyright License"):
* http://www.gnu.org/licenses/license-list.html#StandardMLofNJ
*/
/*
* Copyright 1996-1999 by Scott Hudson, Frank Flannery, C. Scott Ananian
*/
package weka.core.parser.java_cup;
/** This class represents one part (either a symbol or an action) of a
* production. In this base class it contains only an optional label
* string that the user can use to refer to the part within actions.<p>
*
* This is an abstract class.
*
* @see weka.core.parser.java_cup.production
* @version last updated: 11/25/95
* @author Scott Hudson
*/
public abstract class production_part {
/*-----------------------------------------------------------*/
/*--- Constructor(s) ----------------------------------------*/
/*-----------------------------------------------------------*/
/** Simple constructor. */
public production_part(String lab)
{
_label = lab;
}
/*-----------------------------------------------------------*/
/*--- (Access to) Instance Variables ------------------------*/
/*-----------------------------------------------------------*/
/** Optional label for referring to the part within an action (null for
* no label).
*/
protected String _label;
/** Optional label for referring to the part within an action (null for
* no label).
*/
public String label() {return _label;}
/*-----------------------------------------------------------*/
/*--- General Methods ---------------------------------------*/
/*-----------------------------------------------------------*/
/** Indicate if this is an action (rather than a symbol). Here in the
* base class, we don't this know yet, so its an abstract method.
*/
public abstract boolean is_action();
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Equality comparison. */
public boolean equals(production_part other)
{
if (other == null) return false;
/* compare the labels */
if (label() != null)
return label().equals(other.label());
else
return other.label() == null;
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Generic equality comparison. */
public boolean equals(Object other)
{
if (!(other instanceof production_part))
return false;
else
return equals((production_part)other);
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Produce a hash code. */
public int hashCode()
{
return label()==null ? 0 : label().hashCode();
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Convert to a string. */
public String toString()
{
if (label() != null)
return label() + ":";
else
return " ";
}
/*-----------------------------------------------------------*/
}