com.ximpleware.extended.PathExpr Maven / Gradle / Ivy
/*
* Copyright (C) 2002-2012 XimpleWare, [email protected]
*
* This program 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.
*
* This program 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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
package com.ximpleware.extended;
import com.ximpleware.extended.xpath.Expr;
/**
* PathExpr implements the Path expression as defined
* in XPath spec
*
*/
public class PathExpr extends Expr {
Expr fe;
LocationPathExpr lpe;
//boolean first_time;
int evalState;
//FastIntBuffer fib;
intHash ih;
//public int getPositon(){
// return fib.size();
//}
public PathExpr(Expr f, LocationPathExpr l){
fe = f;
lpe = l;
//first_time = true;
evalState = 0;
//fib = new FastIntBuffer(8);
ih = new intHash();
}
public boolean evalBoolean(VTDNavHuge vn) {
boolean a = false;
vn.push2();
// record teh stack size
int size = vn.contextStack2.size;
try{
a = (evalNodeSet(vn) != -1);
}catch (Exception e){
}
//rewind stack
vn.contextStack2.size = size;
reset(vn);
vn.pop2();
return a;
}
public double evalNumber(VTDNavHuge vn) {
int a = -1;
vn.push2();
int size = vn.contextStack2.size;
try {
a =evalNodeSet(vn);
if (a!=-1){
if (vn.getTokenType(a)== VTDNavHuge.TOKEN_ATTR_NAME){
a ++;
}else if (vn.getTokenType(a)== VTDNavHuge.TOKEN_STARTING_TAG) {
a = vn.getText();
}
}
} catch (Exception e){
}
vn.contextStack2.size = size;
reset(vn);
vn.pop2();
try{
if (a!=-1) return vn.parseDouble(a);
}catch (NavExceptionHuge e){
}
return Double.NaN;
}
public int evalNodeSet(VTDNavHuge vn) throws XPathEvalExceptionHuge, NavExceptionHuge {
int a;
while (true) {
switch (evalState) {
case 0: //this state is teh initial state;
a = fe.evalNodeSet(vn);
if (a == -1){
evalState =4;
}
else
evalState = 1;
break;
case 1: // fe returns valid value, then iterate the locationPath
vn.push2();
a = lpe.evalNodeSet(vn);
if (a == -1) {
lpe.reset(vn);
evalState = 3;
} else {
evalState = 2;
if (isUnique(a))
return a;
}
break;
case 2:
a = lpe.evalNodeSet(vn);
if (a == -1) {
lpe.reset(vn);
evalState = 3;
} else{
if (isUnique(a))
return a;
//return a;
}
break;
case 3:
vn.pop2();
a = fe.evalNodeSet(vn);
if (a == -1)
evalState = 4;
else{
vn.push2();
evalState = 2;
}
break;
case 4:
return -1;
default:
throw new XPathEvalExceptionHuge(
"Invalid state evaluating PathExpr");
}
}
//return -1;
}
public String evalString(VTDNavHuge vn) {
vn.push2();
int size = vn.contextStack2.size;
int a = -1;
try {
a = evalNodeSet(vn);
if (a != -1) {
if (vn.getTokenType(a) == VTDNavHuge.TOKEN_ATTR_NAME) {
a++;
}
if (vn.getTokenType(a) == VTDNavHuge.TOKEN_STARTING_TAG) {
a = vn.getText();
}
}
} catch (Exception e) {
}
vn.contextStack2.size = size;
reset(vn);
vn.pop2();
try {
if (a != -1)
return vn.toString(a);
} catch (NavExceptionHuge e) {
}
return "";
}
// The improved version, use hashtable to check for uniqueness
public boolean isUnique(int i){
return ih.isUnique(i);
}
public void reset(VTDNavHuge vn) {
fe.reset(vn);
lpe.reset(vn);
//fib.clear();
ih.reset();
evalState = 0;
}
public String toString() {
return "("+fe +")/" + lpe;
}
public boolean isNumerical() {
return false;
}
public boolean isNodeSet() {
return true;
}
public boolean isString(){
return false;
}
public boolean isBoolean(){
return false;
}
// to support computer context size
// needs to add
public boolean requireContextSize(){
return false;
}
public void setContextSize(int size){
}
public void setPosition(int pos){
}
public int adjust(int n){
int i = fe.adjust(n);
lpe.adjust(n);
if (ih!=null && i==ih.e)
{}
else
ih = new intHash(i);
return i;
}
}