package com.sun.java_cup.internal;
/** This class serves as the base class for entries in a parse action table.
* Full entries will either be SHIFT(state_num), REDUCE(production), NONASSOC,
* or ERROR. Objects of this base class will default to ERROR, while
* the other three types will be represented by subclasses.
*
* @see com.sun.java_cup.internal.reduce_action
* @see com.sun.java_cup.internal.shift_action
* @version last updated: 7/2/96
* @author Frank Flannery
*/
public class parse_action {
/*-----------------------------------------------------------*/
/*--- Constructor(s) ----------------------------------------*/
/*-----------------------------------------------------------*/
/** Simple constructor. */
public parse_action()
{
/* nothing to do in the base class */
}
/*-----------------------------------------------------------*/
/*--- (Access to) Static (Class) Variables ------------------*/
/*-----------------------------------------------------------*/
/** Constant for action type -- error action. */
public static final int ERROR = 0;
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Constant for action type -- shift action. */
public static final int SHIFT = 1;
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Constants for action type -- reduce action. */
public static final int REDUCE = 2;
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Constants for action type -- reduce action. */
public static final int NONASSOC = 3;
/*-----------------------------------------------------------*/
/*--- General Methods ---------------------------------------*/
/*-----------------------------------------------------------*/
/** Quick access to the type -- base class defaults to error. */
public int kind() {return ERROR;}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Equality test. */
public boolean equals(parse_action other)
{
/* we match all error actions */
return other != null && other.kind() == ERROR;
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Generic equality test. */
public boolean equals(Object other)
{
if (other instanceof parse_action)
return equals((parse_action)other);
else
return false;
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Compute a hash code. */
public int hashCode()
{
/* all objects of this class hash together */
return 0xCafe123;
}
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
/** Convert to string. */
public String toString() {return "ERROR";}
/*-----------------------------------------------------------*/
}
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