com.ximpleware.extended.intHash 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;
/**
*
* This is the implementation of a hash table for integers
* It is used by various XPath expressions to check for uniqueness
* of a node
*/
class intHash {
private int mask1 = 0x7ff;
//2048
private int mask2 = 0xfffff800;
private int pageSizeE = 4; // 32 * 4 bytes
protected FastIntBuffer[] storage;
private int hashWidth = 1<<11;
private int maxDepth;
protected int e;
/**
* Test whether the input i is unique;
* if not, insert into the hash table and return false
* otherwise, return true
*/
public boolean isUnique(int i){
int temp = i & mask1;
if (temp>maxDepth){
maxDepth = temp;
}
if (storage[temp]==null) {
storage[temp]= new FastIntBuffer(pageSizeE);
storage[temp].append(i);
return true;
}
else{
int size = storage[temp].size();
for (int j=0;j