/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.es.parser;
import com.caucho.es.ESException;
import com.caucho.es.ESString;
import java.io.IOException;
/**
* Expr is an intermediate form representing an expression.
*/
class PlusExpr extends Expr {
Expr left;
Expr right;
int op;
private PlusExpr(Block block, Expr left, Expr right)
{
super(block);
this.left = left;
this.right = right;
}
/**
* When possible, reorder the arguments to avoid allocating an extra
* char buffer.
*
* x + ("b" + y) -> (x + "b") + y
*/
static Expr create(Block block, Expr left, Expr right)
throws ESException
{
if (left instanceof LiteralExpr &&
right instanceof LiteralExpr &&
(left.getType() == TYPE_STRING || right.getType() == TYPE_STRING)) {
LiteralExpr leftLit = (LiteralExpr) left;
LiteralExpr rightLit = (LiteralExpr) right;
String string = leftLit.getLiteral().toString() + rightLit.getLiteral();
return new LiteralExpr(block, ESString.create(string));
}
if (! (right instanceof PlusExpr) ||
right.getType() != TYPE_STRING)
return new PlusExpr(block, left, right);
PlusExpr pright = (PlusExpr) right;
if (pright.left.getType() == TYPE_STRING)
return create(block, create(block, left, pright.left), pright.right);
else
return new PlusExpr(block, left, right);
}
int getType()
{
int ltype = left.getType();
int rtype = right.getType();
if (ltype == TYPE_INTEGER && rtype == TYPE_INTEGER)
return TYPE_INTEGER;
else if (ltype == TYPE_STRING || rtype == TYPE_STRING)
return TYPE_STRING;
else if (left.isNumeric() && right.isNumeric()) {
return TYPE_NUMBER;
}
else
return TYPE_ES;
}
void exprStatement(Function fun) throws ESException
{
left.exprStatement(fun);
right.exprStatement(fun);
}
void printInt32Impl() throws IOException
{
cl.print("(");
left.printInt32();
cl.print("+");
right.printInt32();
cl.print(")");
}
void printNumImpl() throws IOException
{
cl.print("(");
left.printNum();
cl.print("+");
right.printNum();
cl.print(")");
}
void printStringImpl() throws IOException
{
printCharBufferAppend();
cl.print(".close()");
}
void printCharBufferAppend() throws IOException
{
if (left instanceof PlusExpr && left.getType() == TYPE_STRING) {
((PlusExpr) left).printCharBufferAppend();
}
else {
cl.print("CharBuffer.allocate()");
cl.print(".append(");
left.printJavaString();
cl.print(")");
}
cl.print(".append(");
right.printJavaString();
cl.print(")");
}
void printImpl() throws IOException
{
left.print();
cl.print(".plus(");
right.print();
cl.print(")");
}
}