/*
* 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 a shift action within the parse table.
* The action simply stores the state that it shifts to and responds
* to queries about its type.
*
* @version last updated: 11/25/95
* @author Scott Hudson
*/
public class shift_action extends parse_action {
/*-----------------------------------------------------------*/
/*--- Constructor(s) ----------------------------------------*/
/*-----------------------------------------------------------*/
/** Simple constructor.
* @param shft_to the state that this action shifts to.
*/
public shift_action(lalr_state shft_to) throws internal_error
{
/* sanity check */
if (shft_to == null)
throw new internal_error(
"Attempt to create a shift_action to a null state");
_shift_to = shft_to;
}
/*-----------------------------------------------------------*/
/*--- (Access to) Instance Variables ------------------------*/
/*-----------------------------------------------------------*/
/** The state we shift to. */
protected lalr_state _shift_to;
/** The state we shift to. */
public lalr_state shift_to() {return _shift_to;}
/*-----------------------------------------------------------*/
/*--- General Methods ---------------------------------------*/
/*-----------------------------------------------------------*/
/** Quick access to type of action. */
public int kind() {return SHIFT;}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Equality test. */
public boolean equals(shift_action other)
{
return other != null && other.shift_to() == shift_to();
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Generic equality test. */
public boolean equals(Object other)
{
if (other instanceof shift_action)
return equals((shift_action)other);
else
return false;
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Compute a hash code. */
public int hashCode()
{
/* use the hash code of the state we are shifting to */
return shift_to().hashCode();
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Convert to a string. */
public String toString() {return "SHIFT(to state " + shift_to().index() + ")";}
/*-----------------------------------------------------------*/
}