/*
* $Id: ChainedComparisonNode.java,v 1.5 2002/09/16 08:05:04 jkl Exp $
*
* Copyright (c) 2002 Njet Communications Ltd. All Rights Reserved.
*
* Use is subject to license terms, as defined in
* Anvil Sofware License, Version 1.1. See LICENSE
* file, or http://njet.org/license-1.1.txt
*/
package anvil.script.expression;
import anvil.core.Any;
import anvil.core.Any.Op;
import anvil.codec.Code;
import anvil.codec.Source;
import anvil.script.compiler.ByteCompiler;
import anvil.script.Context;
import anvil.script.parser.ParserBaseConstants;
import java.io.IOException;
/**
* class ChainedComparisonNode
*
* @author: Jani Lehtim�ki
*/
public class ChainedComparisonNode extends MultiParent
implements ParserBaseConstants
{
private int[] _op;
public ChainedComparisonNode(Node[] child, int[] op)
{
super(child);
_op = op;
}
public int typeOf()
{
return Node.EXPR_COMPARISON_CHAIN;
}
public String getOp(int op)
{
switch(op) {
case LESS:
return "<";
case LESS_OR_EQUAL:
return "<=";
case GREATER_OR_EQUAL:
return ">=";
case GREATER:
return ">";
default:
return "";
}
}
public Any eval()
{
Any a = getChild(0).eval();
Any b;
int n = childs();
for(int i = 1; i < n; i++) {
b = getChild(i).eval();
switch(_op[i-1]) {
case LESS:
if (Op.test(a,b) >= 0) {
return Any.FALSE;
}
break;
case LESS_OR_EQUAL:
if (Op.test(a,b) > 0) {
return Any.FALSE;
}
break;
case GREATER_OR_EQUAL:
if (Op.test(a,b) < 0) {
return Any.FALSE;
}
break;
case GREATER:
if (Op.test(a,b) <= 0) {
return Any.FALSE;
}
break;
}
a = b;
}
return Any.TRUE;
}
public void compile(ByteCompiler context, int operation)
{
Code code = context.getCode();
int n = childs();
int testmethod = code.getPool().addMethodRef(
context.TYPE_ANY_OP, "test", "(Lanvil/core/Any;Lanvil/core/Any;)I");
Source isfalse = code.getSource();
for(int i=0; i<n; i++) {
if (i==0) {
getChild(i++).compile(context, GET);
}
getChild(i).compile(context, GET);
code.dup_x1();
code.invokestatic(testmethod);
switch(_op[i-1]) {
case LESS:
code.if_ge(isfalse);
break;
case LESS_OR_EQUAL:
code.if_gt(isfalse);
break;
case GREATER_OR_EQUAL:
code.if_lt(isfalse);
break;
case GREATER:
code.if_le(isfalse);
break;
default:
code.go_to(isfalse);
}
}
code.pop();
code.iconst(true);
Source toend = code.go_to();
isfalse.bind();
code.pop();
code.iconst(false);
toend.bind();
if (operation != GET_BOOLEAN) {
context.boolean2any();
}
}
}