Milán Major

netscape-revival

1 branch
Code

sun-java/classsrc/sun/tools/tree/LengthExpression.java

/*
 * @(#)LengthExpression.java	1.11 95/09/14 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 sun.tools.asm.Assembler;
import java.util.Hashtable;

public
class LengthExpression extends UnaryExpression {
    /**
     * Constructor
     */
    public LengthExpression(int where, Expression right) {
	super(LENGTH, where, Type.tInt, right);
    }
 
    /**
     * Select the type of the expression
     */
    public long checkValue(Environment env, Context ctx, long vset, Hashtable exp) {
	vset = right.checkValue(env, ctx, vset, exp);
	if (!right.type.isType(TC_ARRAY)) {
	    env.error(where, "invalid.length", right.type);
	}
	return vset;
    }

    /**
     * Code
     */
    public void codeValue(Environment env, Context ctx, Assembler asm) {
	right.codeValue(env, ctx, asm);
	asm.add(where, opc_arraylength);
    }
}