/*
* 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.xpath.expr;
import com.caucho.xml.XmlUtil;
import com.caucho.xpath.Expr;
import com.caucho.xpath.ExprEnvironment;
import com.caucho.xpath.XPathException;
import com.caucho.xpath.pattern.*;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import java.util.ArrayList;
public class ObjectExpr extends Expr {
private int _code;
private String _name;
private Expr _left;
private Expr _right;
private Expr _third;
public ObjectExpr(int code, ArrayList args)
{
_code = code;
if (args != null && args.size() > 0)
_left = (Expr) args.get(0);
if (args != null && args.size() > 1)
_right = (Expr) args.get(1);
if (args != null && args.size() > 2)
_third = (Expr) args.get(2);
if (_right == null || _third == null)
throw new NullPointerException();
}
public ObjectExpr(int code, String name)
{
_code = code;
_name = name;
}
/**
* Returns true if the expression evaluates to a node-set.
*/
public boolean isNodeSet()
{
return _code == SELF;
}
/**
* Returns true if the expression evaluates to a node-set.
*/
public boolean isString()
{
return _code == ATTRIBUTE;
}
/**
* Evaluates the expression as a boolean.
*
* @param node current node
* @param env the environment
*
* @return the boolean value
*/
public boolean evalBoolean(Node node, ExprEnvironment env)
throws XPathException
{
switch (_code) {
case IF:
if (_left.evalBoolean(node, env))
return _right.evalBoolean(node, env);
else
return _third.evalBoolean(node, env);
case ATTRIBUTE:
if (node instanceof Element)
return ! ((Element) node).getAttribute(_name).equals("");
else
return false;
case SELF:
return true;
default:
return toBoolean(evalObject(node, env));
}
}
/**
* Evaluates the expression as number.
*
* @param node current node
* @param env the environment
*/
public double evalNumber(Node node, ExprEnvironment env)
throws XPathException
{
switch (_code) {
case IF:
if (_left.evalBoolean(node, env))
return _right.evalNumber(node, env);
else
return _third.evalNumber(node, env);
case ATTRIBUTE:
if (node instanceof Element)
return toDouble(((Element) node).getAttribute(_name));
else
return Double.NaN;
case SELF:
return toDouble(XmlUtil.textValue(node));
default:
return toDouble(evalObject(node, env));
}
}
/**
* Evaluates the expression as string.
*
* @param node current node
* @param env the environment
*
* @return the string representation
*/
public String evalString(Node node, ExprEnvironment env)
throws XPathException
{
switch (_code) {
case IF:
if (_left.evalBoolean(node, env))
return _right.evalString(node, env);
else
return _third.evalString(node, env);
case ATTRIBUTE:
if (node instanceof Element)
return ((Element) node).getAttribute(_name);
else
return "";
case SELF:
return XmlUtil.textValue(node);
default:
return toString(evalObject(node, env));
}
}
/**
* Evaluates the expression as an object.
*
* @param node current node
* @param env the environment
*
* @return the object representation
*/
public Object evalObject(Node node, ExprEnvironment env)
throws XPathException
{
switch (_code) {
case IF:
if (_left.evalBoolean(node, env))
return _right.evalObject(node, env);
else
return _third.evalObject(node, env);
case SELF:
return node;
case ATTRIBUTE:
if (node instanceof Element)
return ((Element) node).getAttributeNode(_name);
else
return null;
default:
return null;
}
}
/**
* Evaluates the expression as a node set.
*
* @param node current node
* @param env the variable environment
*/
public NodeIterator evalNodeSet(Node node, ExprEnvironment env)
throws XPathException
{
switch (_code) {
case IF:
if (_left.evalBoolean(node, env))
return _right.evalNodeSet(node, env);
else
return _third.evalNodeSet(node, env);
case SELF:
return new SingleNodeIterator(env, node);
case ATTRIBUTE:
if (node instanceof Element)
return new SingleNodeIterator(env, ((Element) node).getAttributeNode(_name));
else
return new SingleNodeIterator(env, null);
default:
return null;
}
}
/**
* Convert from an expression to a pattern.
*/
protected AbstractPattern toNodeList()
{
switch (_code) {
case SELF:
return NodeTypePattern.create(new FromSelf(null), NodeTypePattern.ANY);
case ATTRIBUTE:
return new NodePattern(new FromAttributes(null),
_name, Node.ATTRIBUTE_NODE);
default:
return super.toNodeList();
}
}
public String toString()
{
switch (_code) {
case IF:
return "if(" + _left + "," + _right + "," + _third + ")";
case SELF:
return ".";
case ATTRIBUTE:
return "@" + _name;
default:
return super.toString();
}
}
}