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/*
* ===========================================
* Java Pdf Extraction Decoding Access Library
* ===========================================
*
* Project Info: http://www.idrsolutions.com
* Help section for developers at http://www.idrsolutions.com/support/
*
* (C) Copyright 1997-2015 IDRsolutions and Contributors.
*
* This file is part of JPedal/JPDF2HTML5
*
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* ---------------
* RandomAccessMemoryMapBuffer.java
* ---------------
*/
package org.jpedal.io;
import org.jpedal.utils.LogWriter;
import java.io.*;
public class RandomAccessMemoryMapBuffer implements RandomAccessBuffer {
//private byte[] data;
private long pointer;
private int length;
private File file;
private RandomAccessFile buf;
public RandomAccessMemoryMapBuffer(final InputStream in)
{
this.pointer = -1;
length=0;
FileOutputStream to=null;
BufferedInputStream from=null;
try {
file=File.createTempFile("page",".bin", new File(ObjectStore.temp_dir));
//file.deleteOnExit();
to =new java.io.FileOutputStream(file);
from=new BufferedInputStream(in);
//write
final byte[] buffer = new byte[65535];
int bytes_read;
while ((bytes_read = from.read(buffer)) != -1){
to.write(buffer, 0, bytes_read);
length += bytes_read;
}
} catch (final Exception e) {
//tell user and log
if(LogWriter.isOutput()) {
LogWriter.writeLog("Exception: " + e.getMessage());
}
//
}
//close streams
try {
if(to!=null) {
to.close();
}
if(from!=null) {
from.close();
}
} catch (final Exception e) {
if(LogWriter.isOutput()) {
LogWriter.writeLog("Exception " + e + " closing files");
}
}
try {
init();
} catch (final Exception e) {
//tell user and log
if(LogWriter.isOutput()) {
LogWriter.writeLog("Exception: " + e.getMessage());
}
//
}
}
private void init() throws Exception{
// Create a read-only memory-mapped file
buf=new RandomAccessFile(file, "r");
}
@Override
public long getFilePointer() throws IOException {
return pointer;
}
@Override
public void seek(final long pos) throws IOException {
if ( checkPos(pos) ) {
this.pointer = pos;
} else {
throw new IOException("Position out of bounds");
}
}
@Override
public void close() throws IOException {
if(buf!=null){
buf.close();
buf=null;
}
this.pointer = -1;
if(file!=null && file.exists()){
file.delete();
}
}
/**/
@Override
protected void finalize(){
try {
super.finalize();
} catch (final Throwable e) {
//tell user and log
if(LogWriter.isOutput()) {
LogWriter.writeLog("Exception: " + e.getMessage());
}
//
}
//ensure removal actual file
try {
close();
} catch (final IOException e) {
//tell user and log
if(LogWriter.isOutput()) {
LogWriter.writeLog("Exception: " + e.getMessage());
}
//
}
} /**/
@Override
public long length() throws IOException {
if (buf!=null) {
return length;
} else {
throw new IOException("Data buffer not initialized.");
}
}
@Override
public int read() throws IOException {
if (checkPos(this.pointer)) {
buf.seek(pointer++);
return b2i(buf.readByte());
} else {
return -1;
}
}
private int peek() throws IOException {
if (checkPos(this.pointer)) {
buf.seek(pointer++);
return b2i(buf.readByte());
} else {
return -1;
}
}
/**
* return next line (returns null if no line)
*/
@Override
public String readLine() throws IOException {
if (this.pointer >= this.length - 1) {
return null;
} else {
final StringBuilder buf = new StringBuilder();
int c;
while ((c = read()) >= 0) {
if ((c == 10) || (c == 13)) {
if (((peek() == 10) || (peek() == 13)) && (peek() != c)) {
read();
}
break;
}
buf.append((char) c);
}
return buf.toString();
}
}
@Override
public int read(final byte[] b) throws IOException {
if (buf==null) {
throw new IOException("Data buffer not initialized.");
}
if (pointer<0 || pointer>=length) {
return -1;
}
int length=this.length-(int)pointer;
if(length>b.length) {
length = b.length;
}
//replaced inefficient code with an improved performance version (up to ~60 %)
//buf.seek(pointer);
//buf.read(b);
//pointer += b.length;
for (int i=0; i=0) {
return b;
}
return 256+b;
}
private boolean checkPos(final long pos) throws IOException {
return ( (pos>=0) && (pos