org.jpedal.linear.LinearParser Maven / Gradle / Ivy
/*
* ===========================================
* 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
*
* ---------------
* LinearParser.java
* ---------------
*/
package org.jpedal.linear;
import org.jpedal.FileAccess;
import org.jpedal.exception.PdfException;
import org.jpedal.io.*;
import org.jpedal.objects.raw.LinearizedObject;
import org.jpedal.objects.raw.PageObject;
import org.jpedal.objects.raw.PdfDictionary;
import org.jpedal.objects.raw.PdfObject;
import org.jpedal.parser.PdfStreamDecoder;
import org.jpedal.utils.LogWriter;
import org.jpedal.utils.NumberUtils;
import org.jpedal.utils.repositories.FastByteArrayOutputStream;
import java.io.*;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.HashMap;
import java.util.Map;
public class LinearParser {
/**flag if we have tested - reset for every file*/
public boolean isLinearizationTested;
private PageObject linObject;
private final Map linObjects=new HashMap();
private int linearPageCount=-1;
/**present if file Linearized*/
private PdfObject linearObj;
/**
* hold all data in Linearized Obj
*/
private LinearizedHintTable linHintTable;
private int E=-1;
public org.jpedal.linear.LinearThread linearizedBackgroundReaderer;
public void closePdfFile() {
E=-1;
linearObj=null;
isLinearizationTested =false;
linObjects.clear();
if(linearizedBackgroundReaderer!=null && linearizedBackgroundReaderer.isAlive()){
linearizedBackgroundReaderer.interrupt();
}
//wait to die
while(linearizedBackgroundReaderer !=null && linearizedBackgroundReaderer.isAlive() && !linearizedBackgroundReaderer.isInterrupted()){
try{
Thread.sleep(500);
}catch(final Exception e){
//tell user and log
if(LogWriter.isOutput()) {
LogWriter.writeLog("Exception: " + e.getMessage());
}
//
}
}
linHintTable=null;
}
private void testForLinearlized(final byte[] buffer, final PdfObjectReader currentPdfFile) {
int start=0,end=0;
boolean isLinear=false;
isLinearizationTested =true;
//scan for Linearized in text
final int len=buffer.length;
for(int i=0;i1 && linHintTable!=null){
final Integer key= rawPage;
//cached data
if(linObjects.containsKey(key)){
linObject=(PageObject)linObjects.get(key);
return true;
}
final int objID=linHintTable.getPageObjectRef(rawPage);
//return if Page data not available
final byte[] pageData=linHintTable.getObjData(objID);
if(pageData!=null){
/**
* turn page into obj
*/
linObject=new PageObject(objID+" 0 R");
linObject.setStatus(PdfObject.UNDECODED_DIRECT);
linObject.setUnresolvedData(pageData, PdfDictionary.Page);
linObject.isDataExternal(true);
final PdfFileReader objectReader=currentPdfFile.getObjectReader();
//see if object and all refs loaded otherwise exit
if(!ObjectDecoder.resolveFully(linObject, objectReader)) {
isPageAvailable = false;
} else{ //cache once available
/**
* check content as well
*/
if(linObject!=null){
final byte[] b_data=currentPdfFile.getObjectReader().readPageIntoStream(linObject);
if(b_data==null){
isPageAvailable=false;
}else{
//check Resources
final PdfObject Resources=linObject.getDictionary(PdfDictionary.Resources);
if(Resources==null){
linObject=null;
isPageAvailable=false;
}else if(!ObjectDecoder.resolveFully(Resources, objectReader)){
linObject=null;
isPageAvailable=false;
}else{
Resources.isDataExternal(true);
new PdfStreamDecoder(currentPdfFile).readResources(Resources,true);
if(!Resources.isFullyResolved()){
linObject=null;
isPageAvailable=false;
}
}
}
}
if(isPageAvailable && linObject!=null){
linObjects.put(key,linObject);
}
}
}else {
isPageAvailable = false;
}
}else {
linObject = null;
}
}catch(final Exception e){
//tell user and log
if(LogWriter.isOutput()) {
LogWriter.writeLog("Exception: " + e.getMessage());
}
//
isPageAvailable=false;
}
return isPageAvailable;
}
public byte[] readLinearData(final PdfObjectReader currentPdfFile, final File tempURLFile, final InputStream is, final FileAccess fileAccess) throws IOException {
final FileChannel fos = new RandomAccessFile(tempURLFile,"rws").getChannel();
fos.force(true);
final FastByteArrayOutputStream bos=new FastByteArrayOutputStream(8192);
// Download buffer
final byte[] buffer = new byte[4096];
int read,bytesRead=0;
byte[] b;
//main loop to read all the file bytes (carries on in thread if linearized)
while ((read = is.read(buffer)) != -1) {
if(read>0){
synchronized (fos){
b=new byte[read];
System.arraycopy(buffer,0,b,0,read);
final ByteBuffer f=ByteBuffer.wrap(b);
fos.write(f);
}
}
bytesRead += read;
//see if number of bytes loaded
if(E!=-1){
bos.write(buffer,0,read);
//once correct number of bytes for Linearized object read, start background thread to read rest and process Linearized/page 1
if(E57) //if its not a number value it looks suspicious
{
contentIsDodgy = true;
}
i++;
}
//trap for content not correct
if(!contentIsDodgy){
final int number= NumberUtils.parseInt(keyStart2, i, hintStream);
//generation
while(hintStream[i]==10 || hintStream[i]==13 || hintStream[i]==32 || hintStream[i]==47 || hintStream[i]==60) {
i++;
}
keyStart2=i;
//move cursor to end of reference
while(i<10 && hintStream[i]!=10 && hintStream[i]!=13 && hintStream[i]!=32 && hintStream[i]!=47 && hintStream[i]!=60 && hintStream[i]!=62) {
i++;
}
final int generation= NumberUtils.parseInt(keyStart2, i, hintStream);
while(i © 2015 - 2025 Weber Informatics LLC | Privacy Policy