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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/java-pdf-library-support/
*
* (C) Copyright 1997-2013, IDRsolutions and Contributors.
*
* This file is part of JPedal
*
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 java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.RandomAccessFile;
import org.jpedal.utils.LogWriter;
public class RandomAccessMemoryMapBuffer implements RandomAccessBuffer {
// private byte[] data;
private long pointer;
private int length = 0;
private File file;
private RandomAccessFile buf;
public RandomAccessMemoryMapBuffer(InputStream in) {
this.pointer = -1;
this.length = 0;
FileOutputStream to = null;
BufferedInputStream from = null;
try {
this.file = File.createTempFile("page", ".bin", new File(ObjectStore.temp_dir));
// file.deleteOnExit();
to = new java.io.FileOutputStream(this.file);
from = new BufferedInputStream(in);
// write
byte[] buffer = new byte[65535];
int bytes_read;
while ((bytes_read = from.read(buffer)) != -1) {
to.write(buffer, 0, bytes_read);
this.length = this.length + bytes_read;
}
}
catch (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 (Exception e) {
if (LogWriter.isOutput()) LogWriter.writeLog("Exception " + e + " closing files");
}
try {
init();
}
catch (Exception e) {
// tell user and log
if (LogWriter.isOutput()) LogWriter.writeLog("Exception: " + e.getMessage());
}
}
public RandomAccessMemoryMapBuffer(byte[] data) {
this.pointer = -1;
this.length = data.length;
try {
this.file = File.createTempFile("page", ".bin", new File(ObjectStore.temp_dir));
// file.deleteOnExit();
java.io.FileOutputStream a = new java.io.FileOutputStream(this.file);
a.write(data);
a.flush();
a.close();
init();
}
catch (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
this.buf = new RandomAccessFile(this.file, "r");
}
@Override
public long getFilePointer() throws IOException {
return this.pointer;
}
@Override
public void seek(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 (this.buf != null) {
this.buf.close();
this.buf = null;
}
this.pointer = -1;
if (this.file != null && this.file.exists()) {
this.file.delete();
}
}
/**/@Override
public void finalize() {
try {
super.finalize();
}
catch (Throwable e) {
// tell user and log
if (LogWriter.isOutput()) LogWriter.writeLog("Exception: " + e.getMessage());
}
// ensure removal actual file
try {
close();
}
catch (IOException e) {
// tell user and log
if (LogWriter.isOutput()) LogWriter.writeLog("Exception: " + e.getMessage());
}
} /**/
@Override
public long length() throws IOException {
if (this.buf != null) {
return this.length;
}
else {
throw new IOException("Data buffer not initialized.");
}
}
@Override
public int read() throws IOException {
if (checkPos(this.pointer)) {
this.buf.seek(this.pointer++);
return b2i(this.buf.readByte());
}
else {
return -1;
}
}
private int peek() throws IOException {
if (checkPos(this.pointer)) {
this.buf.seek(this.pointer++);
return b2i(this.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 {
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(byte[] b) throws IOException {
if (this.buf == null) throw new IOException("Data buffer not initialized.");
if (this.pointer < 0 || this.pointer >= this.length) return -1;
int length = this.length - (int) this.pointer;
if (length > b.length) length = b.length;
// replaced inefficient code with an highly improved performance (up to ~60 %)
this.buf.seek(this.pointer);
this.buf.read(b);
this.pointer += b.length;
return length;
}
private static int b2i(byte b) {
if (b >= 0) return b;
return 256 + b;
}
private boolean checkPos(long pos) throws IOException {
return ((pos >= 0) && (pos < length()));
}
/* returns the byte data */
@Override
public byte[] getPdfBuffer() {
byte[] bytes = new byte[this.length];
try {
this.buf.seek(0);
this.buf.read(bytes);
}
catch (IOException e) {
// tell user and log
if (LogWriter.isOutput()) LogWriter.writeLog("Exception: " + e.getMessage());
}
return bytes;
}
}