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XimpleWare's VTD-XML is, far and away, the industry's most advanced and powerful XML processing model for SOA and Cloud Computing
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/*
* Copyright (C) 2002-2016 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.
*/
/*VTD-XML is protected by US patent 7133857, 7260652, an 7761459*/
package com.ximpleware.extended;
import java.io.*;
import java.nio.*;
import java.nio.channels.*;
/**
*
* XMLMemMappedBuffer maps an XML document into memory using memory map.
* It avoids the complete loading of the document in memory thus making it
* possible to process very large files. But the trade off is potentially
* lower performance due to disk IO.
*/
public class XMLMemMappedBuffer implements IByteBuffer {
MappedByteBuffer input[];
FileChannel fc;
RandomAccessFile raf;
String fn;
long length;
public XMLMemMappedBuffer(){
}
public long length(){
return length;
}
public byte byteAt(long index){
return input[(int)(index>>30)].get((int)(index & 0x3fffffff));
}
public void readFile(String fileName) throws java.io.IOException, ParseExceptionHuge {
File f = new File(fileName);
fn = fileName;
long l = f.length();
length = l;
if (l>= (1L<< 38)){
throw new ParseExceptionHuge("document too big > 256 Gbyte");
}
raf = new RandomAccessFile(fileName, "r");
fc = raf.getChannel();
int pageNumber = (int)(l>>30)+(((l & 0x3fffffffL)==0)?0:1);
input = new MappedByteBuffer[pageNumber];
long l2 =0;
for (int i=0;i