/*
* @(#)BinaryLogicalExpression.java 1.13 95/11/12 Arthur van Hoff
*
* Copyright (c) 1994 Sun Microsystems, Inc. All Rights Reserved.
*
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file "copyright.html"
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*/
package sun.tools.tree;
import sun.tools.java.*;
import java.util.Hashtable;
abstract public
class BinaryLogicalExpression extends BinaryExpression {
/**
* constructor
*/
public BinaryLogicalExpression(int op, int where, Expression left, Expression right) {
super(op, where, Type.tBoolean, left, right);
}
/**
* Check a binary expression
*/
public long checkValue(Environment env, Context ctx,
long vset, Hashtable exp) {
ConditionVars cvars = new ConditionVars();
// evaluate the logical expression, determining which variables are
// set if the resulting value is true or false
checkCondition(env, ctx, vset, exp, cvars);
// return the intersection.
return cvars.vsTrue & cvars.vsFalse;
}
/*
* Every subclass of this class must define a genuine implementation
* of this method. It cannot inherit the method of Expression.
*/
abstract
public void checkCondition(Environment env, Context ctx, long vset,
Hashtable exp, ConditionVars cvars);
}