/**
* Copyright (c) 2003-2005, www.pdfbox.org
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. Neither the name of pdfbox; nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* http://www.pdfbox.org
*
*/
package org.pdfbox.pdfwriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Set;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import org.pdfbox.persistence.util.COSObjectKey;
import org.pdfbox.cos.COSBase;
import org.pdfbox.cos.COSFloat;
import org.pdfbox.cos.ICOSVisitor;
import org.pdfbox.cos.COSName;
import org.pdfbox.cos.COSString;
import org.pdfbox.cos.COSBoolean;
import org.pdfbox.cos.COSArray;
import org.pdfbox.cos.COSDocument;
import org.pdfbox.cos.COSStream;
import org.pdfbox.cos.COSObject;
import org.pdfbox.encryption.DocumentEncryption;
import org.pdfbox.exceptions.COSVisitorException;
import org.pdfbox.exceptions.CryptographyException;
import org.pdfbox.cos.COSDictionary;
import org.pdfbox.cos.COSInteger;
import org.pdfbox.cos.COSNull;
import org.pdfbox.pdmodel.PDDocument;
import org.apache.log4j.Logger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* this class acts on a in-memory representation of a pdf document.
*
* todo no support for incremental updates
* todo single xref section only
* todo no linearization
*
* @author Michael Traut
* @author Ben Litchfield (ben@benlitchfield.com)
* @version $Revision: 1.32 $
*/
public class COSWriter implements ICOSVisitor
{
private static Logger log = Logger.getLogger( COSWriter.class );
/**
* The dictionary open token.
*/
public static final byte[] DICT_OPEN = "<<".getBytes();
/**
* The dictionary close token.
*/
public static final byte[] DICT_CLOSE = ">>".getBytes();
/**
* space character.
*/
public static final byte[] SPACE = " ".getBytes();
/**
* The start to a PDF comment.
*/
public static final byte[] COMMENT = "%".getBytes();
/**
* The output version of the PDF.
*/
public static final byte[] VERSION = "PDF-1.4".getBytes();
/**
* Garbage bytes used to create the PDF header.
*/
public static final byte[] GARBAGE = new byte[] {(byte)0xf6, (byte)0xe4, (byte)0xfc, (byte)0xdf};
/**
* The EOF constant.
*/
public static final byte[] EOF = "%%EOF".getBytes();
// pdf tokens
/**
* The reference token.
*/
public static final byte[] REFERENCE = "R".getBytes();
/**
* The XREF token.
*/
public static final byte[] XREF = "xref".getBytes();
/**
* The xref free token.
*/
public static final byte[] XREF_FREE = "f".getBytes();
/**
* The xref used token.
*/
public static final byte[] XREF_USED = "n".getBytes();
/**
* The trailer token.
*/
public static final byte[] TRAILER = "trailer".getBytes();
/**
* The start xref token.
*/
public static final byte[] STARTXREF = "startxref".getBytes();
/**
* The starting object token.
*/
public static final byte[] OBJ = "obj".getBytes();
/**
* The end object token.
*/
public static final byte[] ENDOBJ = "endobj".getBytes();
/**
* The array open token.
*/
public static final byte[] ARRAY_OPEN = "[".getBytes();
/**
* The array close token.
*/
public static final byte[] ARRAY_CLOSE = "]".getBytes();
/**
* The open stream token.
*/
public static final byte[] STREAM = "stream".getBytes();
/**
* The close stream token.
*/
public static final byte[] ENDSTREAM = "endstream".getBytes();
private NumberFormat formatXrefOffset = new DecimalFormat("0000000000");
/**
* The decimal format for the xref object generation number data.
*/
private NumberFormat formatXrefGeneration = new DecimalFormat("00000");
private NumberFormat formatDecimal = NumberFormat.getNumberInstance( Locale.US );
// the stream where we create the pdf output
private OutputStream output;
// the stream used to write standard cos data
private COSStandardOutputStream standardOutput;
// the start position of the x ref section
private long startxref = 0;
// the current object number
private long number = 0;
// maps the object to the keys generated in the writer
// these are used for indirect refrences in other objects
//A hashtable is used on purpose over a hashmap
//so that null entries will not get added.
private Map objectKeys = new Hashtable();
// the list of x ref entries to be made so far
private List xRefEntries = new ArrayList();
//A list of objects to write.
private List objectsToWrite = new ArrayList();
//a list of objects already written
private Set writtenObjects = new HashSet();
//An 'actual' is any COSBase that is not a COSObject.
//need to keep a list of the actuals that are added
//as well as the objects because there is a problem
//when adding a COSObject and then later adding
//the actual for that object, so we will track
//actuals separately.
private Set actualsAdded = new HashSet();
private COSObjectKey currentObjectKey = null;
private PDDocument document = null;
private DocumentEncryption enc = null;
/**
* COSWriter constructor comment.
*
* @param os The wrapped output stream.
*/
public COSWriter(OutputStream os)
{
super();
setOutput(os);
setStandardOutput(new COSStandardOutputStream(getOutput()));
formatDecimal.setMaximumFractionDigits( 10 );
formatDecimal.setGroupingUsed( false );
}
/**
* add an entry in the x ref table for later dump.
*
* @param entry The new entry to add.
*/
protected void addXRefEntry(COSWriterXRefEntry entry)
{
getXRefEntries().add(entry);
}
/**
* This will close the stream.
*
* @throws IOException If the underlying stream throws an exception.
*/
public void close() throws IOException
{
if (getStandardOutput() != null)
{
getStandardOutput().close();
}
if (getOutput() != null)
{
getOutput().close();
}
}
/**
* This will get the current object number.
*
* @return The current object number.
*/
protected long getNumber()
{
return number;
}
/**
* This will get all available object keys.
*
* @return A map of all object keys.
*/
public java.util.Map getObjectKeys()
{
return objectKeys;
}
/**
* This will get the output stream.
*
* @return The output stream.
*/
protected java.io.OutputStream getOutput()
{
return output;
}
/**
* This will get the standard output stream.
*
* @return The standard output stream.
*/
protected COSStandardOutputStream getStandardOutput()
{
return standardOutput;
}
/**
* This will get the current start xref.
*
* @return The current start xref.
*/
protected long getStartxref()
{
return startxref;
}
/**
* This will get the xref entries.
*
* @return All available xref entries.
*/
protected java.util.List getXRefEntries()
{
return xRefEntries;
}
/**
* This will set the current object number.
*
* @param newNumber The new object number.
*/
protected void setNumber(long newNumber)
{
number = newNumber;
}
/**
* This will set the output stream.
*
* @param newOutput The new output stream.
*/
private void setOutput( OutputStream newOutput )
{
output = newOutput;
}
/**
* This will set the standard output stream.
*
* @param newStandardOutput The new standard output stream.
*/
private void setStandardOutput(COSStandardOutputStream newStandardOutput)
{
standardOutput = newStandardOutput;
}
/**
* This will set the start xref.
*
* @param newStartxref The new start xref attribute.
*/
protected void setStartxref(long newStartxref)
{
startxref = newStartxref;
}
/**
* This will write the body of the document.
*
* @param doc The document to write the body for.
*
* @throws IOException If there is an error writing the data.
* @throws COSVisitorException If there is an error generating the data.
*/
protected void doWriteBody(COSDocument doc) throws IOException, COSVisitorException
{
COSDictionary trailer = doc.getTrailer();
COSDictionary root = (COSDictionary)trailer.getDictionaryObject( COSName.ROOT );
COSDictionary info = (COSDictionary)trailer.getDictionaryObject( COSName.getPDFName( "Info" ) );
COSDictionary encrypt = (COSDictionary)trailer.getDictionaryObject( COSName.getPDFName( "Encrypt" ) );
if( root != null )
{
addObjectToWrite( root );
}
if( info != null )
{
addObjectToWrite( info );
}
while( objectsToWrite.size() > 0 )
{
COSBase nextObject = (COSBase)objectsToWrite.remove( 0 );
doWriteObject( nextObject );
}
document.clearWillEncryptWhenSaving();
if( encrypt != null )
{
addObjectToWrite( encrypt );
}
while( objectsToWrite.size() > 0 )
{
COSBase nextObject = (COSBase)objectsToWrite.remove( 0 );
doWriteObject( nextObject );
}
// write all objects
/**
for (Iterator i = doc.getObjects().iterator(); i.hasNext();)
{
COSObject obj = (COSObject) i.next();
doWriteObject(obj);
}**/
}
private void addObjectToWrite( COSBase object )
{
COSBase actual = object;
if( actual instanceof COSObject )
{
actual = ((COSObject)actual).getObject();
}
if( !writtenObjects.contains( object ) &&
!objectsToWrite.contains( object ) &&
!actualsAdded.contains( actual ) )
{
objectsToWrite.add( object );
if( actual != null )
{
actualsAdded.add( actual );
}
}
}
/**
* This will write a COS object.
*
* @param obj The object to write.
*
* @throws COSVisitorException If there is an error visiting objects.
*/
public void doWriteObject( COSBase obj ) throws COSVisitorException
{
try
{
writtenObjects.add( obj );
// find the physical reference
currentObjectKey = getObjectKey( obj );
// add a x ref entry
addXRefEntry( new COSWriterXRefEntry(getStandardOutput().getPos(), obj, currentObjectKey));
// write the object
getStandardOutput().write(String.valueOf(currentObjectKey.getNumber()).getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(String.valueOf(currentObjectKey.getGeneration()).getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(OBJ);
getStandardOutput().writeEOL();
obj.accept( this );
getStandardOutput().writeEOL();
getStandardOutput().write(ENDOBJ);
getStandardOutput().writeEOL();
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* This will write the header to the PDF document.
*
* @param doc The document to get the data from.
*
* @throws IOException If there is an error writing to the stream.
*/
protected void doWriteHeader(COSDocument doc) throws IOException
{
getStandardOutput().write( doc.getHeaderString().getBytes() );
getStandardOutput().writeEOL();
getStandardOutput().write(COMMENT);
getStandardOutput().write(GARBAGE);
getStandardOutput().writeEOL();
}
/**
* This will write the trailer to the PDF document.
*
* @param doc The document to create the trailer for.
*
* @throws IOException If there is an IOError while writing the document.
* @throws COSVisitorException If there is an error while generating the data.
*/
protected void doWriteTrailer(COSDocument doc) throws IOException, COSVisitorException
{
getStandardOutput().write(TRAILER);
getStandardOutput().writeEOL();
COSDictionary trailer = doc.getTrailer();
//sort xref, needed only if object keys not regenerated
Collections.sort(getXRefEntries());
COSWriterXRefEntry lastEntry = (COSWriterXRefEntry)getXRefEntries().get( getXRefEntries().size()-1);
trailer.setInt(COSName.getPDFName("Size"), (int)lastEntry.getKey().getNumber()+1);
trailer.removeItem( COSName.PREV );
/**
COSObject catalog = doc.getCatalog();
if (catalog != null)
{
trailer.setItem(COSName.getPDFName("Root"), catalog);
}
*/
trailer.accept(this);
getStandardOutput().write(STARTXREF);
getStandardOutput().writeEOL();
getStandardOutput().write(String.valueOf(getStartxref()).getBytes());
getStandardOutput().writeEOL();
getStandardOutput().write(EOF);
}
/**
* write the x ref section for the pdf file
*
* currently, the pdf is reconstructed from the scratch, so we write a single section
*
* todo support for incremental writing?
*
* @param doc The document to write the xref from.
*
* @throws IOException If there is an error writing the data to the stream.
*/
protected void doWriteXRef(COSDocument doc) throws IOException
{
String offset;
String generation;
// sort xref, needed only if object keys not regenerated
Collections.sort(getXRefEntries());
COSWriterXRefEntry lastEntry = (COSWriterXRefEntry)getXRefEntries().get( getXRefEntries().size()-1 );
// remember the position where x ref is written
setStartxref(getStandardOutput().getPos());
//
getStandardOutput().write(XREF);
getStandardOutput().writeEOL();
// write start object number and object count for this x ref section
// we assume starting from scratch
getStandardOutput().write(String.valueOf(0).getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(String.valueOf(lastEntry.getKey().getNumber() + 1).getBytes());
getStandardOutput().writeEOL();
// write initial start object with ref to first deleted object and magic generation number
offset = formatXrefOffset.format(0);
generation = formatXrefGeneration.format(65535);
getStandardOutput().write(offset.getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(generation.getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(XREF_FREE);
getStandardOutput().writeCRLF();
// write entry for every object
long lastObjectNumber = 0;
for (Iterator i = getXRefEntries().iterator(); i.hasNext();)
{
COSWriterXRefEntry entry = (COSWriterXRefEntry) i.next();
while( lastObjectNumber<entry.getKey().getNumber()-1 )
{
offset = formatXrefOffset.format(0);
generation = formatXrefGeneration.format(65535);
getStandardOutput().write(offset.getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(generation.getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(XREF_FREE);
getStandardOutput().writeCRLF();
lastObjectNumber++;
}
lastObjectNumber = entry.getKey().getNumber();
offset = formatXrefOffset.format(entry.getOffset());
generation = formatXrefGeneration.format(entry.getKey().getGeneration());
getStandardOutput().write(offset.getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(generation.getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(entry.isFree() ? XREF_FREE : XREF_USED);
getStandardOutput().writeCRLF();
}
}
/**
* This will get the object key for the object.
*
* @param obj The object to get the key for.
*
* @return The object key for the object.
*/
private COSObjectKey getObjectKey( COSBase obj )
{
COSBase actual = obj;
if( actual instanceof COSObject )
{
actual = ((COSObject)obj).getObject();
}
COSObjectKey key = null;
if( actual != null )
{
key = (COSObjectKey)objectKeys.get(actual);
}
if( key == null )
{
key = (COSObjectKey)objectKeys.get(obj);
}
if (key == null)
{
setNumber(getNumber()+1);
key = new COSObjectKey(getNumber(),0);
objectKeys.put(obj, key);
if( actual != null )
{
objectKeys.put(actual, key);
}
}
return key;
}
/**
* visitFromArray method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromArray( COSArray obj ) throws COSVisitorException
{
try
{
int count = 0;
getStandardOutput().write(ARRAY_OPEN);
for (Iterator i = obj.iterator(); i.hasNext();)
{
COSBase current = (COSBase) i.next();
if( current instanceof COSDictionary )
{
addObjectToWrite( current );
writeReference( current );
}
else if( current instanceof COSObject )
{
COSBase subValue = ((COSObject)current).getObject();
if( subValue instanceof COSDictionary || subValue == null )
{
addObjectToWrite( current );
writeReference( current );
}
else
{
subValue.accept( this );
}
}
else if( current == null )
{
COSNull.NULL.accept( this );
}
else
{
current.accept(this);
}
count++;
if (i.hasNext())
{
if (count % 10 == 0)
{
getStandardOutput().writeEOL();
}
else
{
getStandardOutput().write(SPACE);
}
}
}
getStandardOutput().write(ARRAY_CLOSE);
getStandardOutput().writeEOL();
return null;
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromBoolean method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromBoolean(COSBoolean obj) throws COSVisitorException
{
try
{
obj.writePDF( getStandardOutput() );
return null;
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromDictionary method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromDictionary(COSDictionary obj) throws COSVisitorException
{
try
{
getStandardOutput().write(DICT_OPEN);
getStandardOutput().writeEOL();
for (Iterator i = obj.keyList().iterator(); i.hasNext();)
{
COSName name = (COSName) i.next();
COSBase value = obj.getItem(name);
if (value != null)
{
// this is purely defensive, if entry is set to null instead of removed
if( value != null )
{
name.accept(this);
getStandardOutput().write(SPACE);
}
if( value == null )
{
log.debug( "Value is null" );
//then we won't write anything, there are a couple cases
//were the value of an entry in the COSDictionary will
//be a dangling reference that points to nothing
//so we will just not write out the entry if that is the case
}
else if( value instanceof COSDictionary )
{
addObjectToWrite( value );
writeReference( value );
}
else if( value instanceof COSObject )
{
COSBase subValue = ((COSObject)value).getObject();
if( subValue instanceof COSDictionary || subValue == null )
{
addObjectToWrite( value );
writeReference( value );
}
else
{
subValue.accept( this );
}
}
else
{
value.accept(this);
}
getStandardOutput().writeEOL();
}
}
getStandardOutput().write(DICT_CLOSE);
getStandardOutput().writeEOL();
return null;
}
catch( IOException e )
{
throw new COSVisitorException(e);
}
}
/**
* The visit from document method.
*
* @param doc The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromDocument(COSDocument doc) throws COSVisitorException
{
try
{
doWriteHeader(doc);
doWriteBody(doc);
doWriteXRef(doc);
doWriteTrailer(doc);
return null;
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromFloat method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromFloat(COSFloat obj) throws COSVisitorException
{
try
{
obj.writePDF( getStandardOutput() );
return null;
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromFloat method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromInt(COSInteger obj) throws COSVisitorException
{
try
{
obj.writePDF( getStandardOutput() );
return null;
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromName method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromName(COSName obj) throws COSVisitorException
{
try
{
obj.writePDF( getStandardOutput() );
return null;
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromNull method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromNull(COSNull obj) throws COSVisitorException
{
try
{
obj.writePDF( getStandardOutput() );
return null;
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromObjRef method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*/
public void writeReference(COSBase obj) throws COSVisitorException
{
try
{
COSObjectKey key = getObjectKey(obj);
getStandardOutput().write(String.valueOf(key.getNumber()).getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(String.valueOf(key.getGeneration()).getBytes());
getStandardOutput().write(SPACE);
getStandardOutput().write(REFERENCE);
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
}
/**
* visitFromStream method comment.
*
* @param obj The object that is being visited.
*
* @throws COSVisitorException If there is an exception while visiting this object.
*
* @return null
*/
public Object visitFromStream(COSStream obj) throws COSVisitorException
{
try
{
if( document.willEncryptWhenSaving() )
{
enc.decryptStream( obj, currentObjectKey.getNumber(), currentObjectKey.getGeneration() );
}
InputStream input = obj.getFilteredStream();
// set the length of the stream and write stream dictionary
COSObject lengthObject = new COSObject( null );
obj.setItem(COSName.LENGTH, lengthObject);
//obj.accept(this);
// write the stream content
visitFromDictionary( obj );
getStandardOutput().write(STREAM);
getStandardOutput().writeCRLF();
byte[] buffer = new byte[1024];
int amountRead = 0;
int totalAmountWritten = 0;
while( (amountRead = input.read(buffer,0,1024)) != -1 )
{
getStandardOutput().write( buffer, 0, amountRead );
totalAmountWritten += amountRead;
}
lengthObject.setObject( new COSInteger( totalAmountWritten ) );
getStandardOutput().writeCRLF();
getStandardOutput().write(ENDSTREAM);
getStandardOutput().writeEOL();
return null;
}
catch( Exception e )
{
throw new COSVisitorException(e);
}
}
/**
* visitFromString method comment.
*
* @param obj The object that is being visited.
*
* @return null
*
* @throws COSVisitorException If there is an exception while visiting this object.
*/
public Object visitFromString(COSString obj) throws COSVisitorException
{
try
{
if( document.willEncryptWhenSaving() )
{
try
{
enc.decryptString( obj, currentObjectKey.getNumber(), currentObjectKey.getGeneration() );
}
catch( Exception e )
{
throw new COSVisitorException( e );
}
}
obj.writePDF( getStandardOutput() );
}
catch (IOException e)
{
throw new COSVisitorException(e);
}
return null;
}
/**
* This will write the pdf document.
*
* @param doc The document to write.
*
* @throws COSVisitorException If an error occurs while generating the data.
*/
public void write(COSDocument doc) throws COSVisitorException
{
PDDocument pdDoc = new PDDocument( doc );
write( pdDoc );
}
/**
* This will write the pdf document.
*
* @param doc The document to write.
*
* @throws COSVisitorException If an error occurs while generating the data.
*/
public void write(PDDocument doc) throws COSVisitorException
{
document = doc;
if( document.willEncryptWhenSaving() )
{
try
{
enc = new DocumentEncryption(document);
enc.initForEncryption();
}
catch( CryptographyException e )
{
throw new COSVisitorException( e );
}
catch( IOException e )
{
throw new COSVisitorException( e );
}
}
COSDocument cosDoc = document.getDocument();
COSDictionary trailer = cosDoc.getTrailer();
COSArray idArray = (COSArray)trailer.getDictionaryObject( "ID" );
if( idArray == null )
{
try
{
//algothim says to use time/path/size/values in doc to generate
//the id. We don't have path or size, so do the best we can
MessageDigest md = MessageDigest.getInstance( "MD5" );
md.update( Long.toString( System.currentTimeMillis()).getBytes() );
COSDictionary info = (COSDictionary)trailer.getDictionaryObject( "Info" );
if( info != null )
{
Iterator values = info.getValues().iterator();
while( values.hasNext() )
{
md.update( values.next().toString().getBytes() );
}
}
idArray = new COSArray();
COSString id = new COSString( md.digest() );
idArray.add( id );
idArray.add( id );
trailer.setItem( "ID", idArray );
}
catch( NoSuchAlgorithmException e )
{
throw new COSVisitorException( e );
}
}
/*
List objects = doc.getObjects();
Iterator iter = objects.iterator();
long maxNumber = 0;
while( iter.hasNext() )
{
COSObject object = (COSObject)iter.next();
if( object.getObjectNumber() != null &&
object.getGenerationNumber() != null )
{
COSObjectKey key = new COSObjectKey( object.getObjectNumber().longValue(),
object.getGenerationNumber().longValue() );
objectKeys.put( object.getObject(), key );
objectKeys.put( object, key );
maxNumber = Math.max( key.getNumber(), maxNumber );
setNumber( maxNumber );
}
}*/
cosDoc.accept(this);
}
}