/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pdfbox.pdmodel.common;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.cos.COSStream;
import org.apache.pdfbox.filter.Filter;
import org.apache.pdfbox.filter.FilterManager;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.common.filespecification.PDFileSpecification;
/**
* A PDStream represents a stream in a PDF document. Streams are tied to a single
* PDF document.
*
* @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
* @version $Revision: 1.17 $
*/
public class PDStream implements COSObjectable
{
private COSStream stream;
/**
* This will create a new PDStream object.
*/
protected PDStream()
{
//should only be called by PDMemoryStream
}
/**
* This will create a new PDStream object.
*
* @param document The document that the stream will be part of.
*/
public PDStream( PDDocument document )
{
stream = new COSStream( document.getDocument().getScratchFile() );
}
/**
* Constructor.
*
* @param str The stream parameter.
*/
public PDStream( COSStream str )
{
stream = str;
}
/**
* Constructor. Reads all data from the input stream and embeds it into the
* document, this will close the InputStream.
*
* @param doc The document that will hold the stream.
* @param str The stream parameter.
* @throws IOException If there is an error creating the stream in the document.
*/
public PDStream( PDDocument doc, InputStream str ) throws IOException
{
this( doc, str, false );
}
/**
* Constructor. Reads all data from the input stream and embeds it into the
* document, this will close the InputStream.
*
* @param doc The document that will hold the stream.
* @param str The stream parameter.
* @param filtered True if the stream already has a filter applied.
* @throws IOException If there is an error creating the stream in the document.
*/
public PDStream( PDDocument doc, InputStream str, boolean filtered ) throws IOException
{
OutputStream output = null;
try
{
stream = new COSStream( doc.getDocument().getScratchFile() );
if( filtered )
{
output = stream.createFilteredStream();
}
else
{
output = stream.createUnfilteredStream();
}
byte[] buffer = new byte[ 1024 ];
int amountRead = -1;
while( (amountRead = str.read(buffer)) != -1 )
{
output.write( buffer, 0, amountRead );
}
}
finally
{
if( output != null )
{
output.close();
}
if( str != null )
{
str.close();
}
}
}
/**
* If there are not compression filters on the current stream then this
* will add a compression filter, flate compression for example.
*/
public void addCompression()
{
List filters = getFilters();
if( filters == null )
{
filters = new ArrayList();
filters.add( COSName.FLATE_DECODE );
setFilters( filters );
}
}
/**
* Create a pd stream from either a regular COSStream on a COSArray of cos streams.
* @param base Either a COSStream or COSArray.
* @return A PDStream or null if base is null.
* @throws IOException If there is an error creating the PDStream.
*/
public static PDStream createFromCOS( COSBase base ) throws IOException
{
PDStream retval = null;
if( base instanceof COSStream )
{
retval = new PDStream( (COSStream)base );
}
else if( base instanceof COSArray )
{
if (((COSArray)base).size() > 0) {
retval = new PDStream( new COSStreamArray( (COSArray)base ) );
}
}
else
{
if( base != null )
{
throw new IOException( "Contents are unknown type:" + base.getClass().getName() );
}
}
return retval;
}
/**
* Convert this standard java object to a COS object.
*
* @return The cos object that matches this Java object.
*/
public COSBase getCOSObject()
{
return stream;
}
/**
* This will get a stream that can be written to.
*
* @return An output stream to write data to.
*
* @throws IOException If an IO error occurs during writing.
*/
public OutputStream createOutputStream() throws IOException
{
return stream.createUnfilteredStream();
}
/**
* This will get a stream that can be read from.
*
* @return An input stream that can be read from.
*
* @throws IOException If an IO error occurs during reading.
*/
public InputStream createInputStream() throws IOException
{
return stream.getUnfilteredStream();
}
/**
* This will get a stream with some filters applied but not others. This is useful
* when doing images, ie filters = [flate,dct], we want to remove flate but leave dct
*
* @param stopFilters A list of filters to stop decoding at.
* @return A stream with decoded data.
* @throws IOException If there is an error processing the stream.
*/
public InputStream getPartiallyFilteredStream( List stopFilters ) throws IOException
{
FilterManager manager = stream.getFilterManager();
InputStream is = stream.getFilteredStream();
ByteArrayOutputStream os = new ByteArrayOutputStream();
List filters = getFilters();
String nextFilter = null;
boolean done = false;
for( int i=0; i<filters.size() && !done; i++ )
{
os.reset();
nextFilter = (String)filters.get( i );
if( stopFilters.contains( nextFilter ) )
{
done = true;
}
else
{
Filter filter = manager.getFilter( COSName.getPDFName(nextFilter) );
filter.decode( is, os, stream, i );
is = new ByteArrayInputStream( os.toByteArray() );
}
}
return is;
}
/**
* Get the cos stream associated with this object.
*
* @return The cos object that matches this Java object.
*/
public COSStream getStream()
{
return stream;
}
/**
* This will get the length of the filtered/compressed stream. This is readonly in the
* PD Model and will be managed by this class.
*
* @return The length of the filtered stream.
*/
public int getLength()
{
return stream.getInt( "Length", 0 );
}
/**
* This will get the list of filters that are associated with this stream. Or
* null if there are none.
* @return A list of all encoding filters to apply to this stream.
*/
public List getFilters()
{
List retval = null;
COSBase filters = stream.getFilters();
if( filters instanceof COSName )
{
COSName name = (COSName)filters;
retval = new COSArrayList( name.getName(), name, stream, COSName.FILTER );
}
else if( filters instanceof COSArray )
{
retval = COSArrayList.convertCOSNameCOSArrayToList( (COSArray)filters );
}
return retval;
}
/**
* This will set the filters that are part of this stream.
*
* @param filters The filters that are part of this stream.
*/
public void setFilters( List filters )
{
COSBase obj = COSArrayList.convertStringListToCOSNameCOSArray( filters );
stream.setItem( COSName.FILTER, obj );
}
/**
* Get the list of decode parameters. Each entry in the list will refer to
* an entry in the filters list.
*
* @return The list of decode parameters.
*
* @throws IOException if there is an error retrieving the parameters.
*/
public List getDecodeParms() throws IOException
{
List retval = null;
COSBase dp = stream.getDictionaryObject( COSName.DECODE_PARMS );
if( dp == null )
{
//See PDF Ref 1.5 implementation note 7, the DP is sometimes used instead.
dp = stream.getDictionaryObject( COSName.DP );
}
if( dp instanceof COSDictionary )
{
Map map = COSDictionaryMap.convertBasicTypesToMap( (COSDictionary)dp );
retval = new COSArrayList(map, dp, stream, COSName.DECODE_PARMS );
}
else if( dp instanceof COSArray )
{
COSArray array = (COSArray)dp;
List actuals = new ArrayList();
for( int i=0; i<array.size(); i++ )
{
actuals.add(
COSDictionaryMap.convertBasicTypesToMap(
(COSDictionary)array.getObject( i ) ) );
}
retval = new COSArrayList(actuals, array);
}
return retval;
}
/**
* This will set the list of decode parameterss.
*
* @param decodeParams The list of decode parameterss.
*/
public void setDecodeParms( List decodeParams )
{
stream.setItem(
COSName.DECODE_PARMS, COSArrayList.converterToCOSArray( decodeParams ) );
}
/**
* This will get the file specification for this stream. This is only
* required for external files.
*
* @return The file specification.
*
* @throws IOException If there is an error creating the file spec.
*/
public PDFileSpecification getFile() throws IOException
{
COSBase f = stream.getDictionaryObject( COSName.F );
PDFileSpecification retval = PDFileSpecification.createFS( f );
return retval;
}
/**
* Set the file specification.
* @param f The file specification.
*/
public void setFile( PDFileSpecification f )
{
stream.setItem( COSName.F, f );
}
/**
* This will get the list of filters that are associated with this stream. Or
* null if there are none.
* @return A list of all encoding filters to apply to this stream.
*/
public List getFileFilters()
{
List retval = null;
COSBase filters = stream.getDictionaryObject( COSName.F_FILTER );
if( filters instanceof COSName )
{
COSName name = (COSName)filters;
retval = new COSArrayList( name.getName(), name, stream, COSName.F_FILTER );
}
else if( filters instanceof COSArray )
{
retval = COSArrayList.convertCOSNameCOSArrayToList( (COSArray)filters );
}
return retval;
}
/**
* This will set the filters that are part of this stream.
*
* @param filters The filters that are part of this stream.
*/
public void setFileFilters( List filters )
{
COSBase obj = COSArrayList.convertStringListToCOSNameCOSArray( filters );
stream.setItem( COSName.F_FILTER, obj );
}
/**
* Get the list of decode parameters. Each entry in the list will refer to
* an entry in the filters list.
*
* @return The list of decode parameters.
*
* @throws IOException if there is an error retrieving the parameters.
*/
public List getFileDecodeParams() throws IOException
{
List retval = null;
COSBase dp = stream.getDictionaryObject( COSName.F_DECODE_PARMS );
if( dp instanceof COSDictionary )
{
Map map = COSDictionaryMap.convertBasicTypesToMap( (COSDictionary)dp );
retval = new COSArrayList(map, dp, stream, COSName.F_DECODE_PARMS );
}
else if( dp instanceof COSArray )
{
COSArray array = (COSArray)dp;
List actuals = new ArrayList();
for( int i=0; i<array.size(); i++ )
{
actuals.add(
COSDictionaryMap.convertBasicTypesToMap(
(COSDictionary)array.getObject( i ) ) );
}
retval = new COSArrayList(actuals, array);
}
return retval;
}
/**
* This will set the list of decode params.
*
* @param decodeParams The list of decode params.
*/
public void setFileDecodeParams( List decodeParams )
{
stream.setItem(
"FDecodeParams", COSArrayList.converterToCOSArray( decodeParams ) );
}
/**
* This will copy the stream into a byte array.
*
* @return The byte array of the filteredStream
* @throws IOException When getFilteredStream did not work
*/
public byte[] getByteArray() throws IOException
{
ByteArrayOutputStream output = new ByteArrayOutputStream();
byte[] buf = new byte[1024];
InputStream is = null;
try
{
is = createInputStream();
int amountRead = -1;
while( (amountRead = is.read( buf )) != -1)
{
output.write( buf, 0, amountRead );
}
}
finally
{
if( is != null )
{
is.close();
}
}
return output.toByteArray();
}
/**
* A convenience method to get this stream as a string. Uses
* the default system encoding.
*
* @return a String representation of this (input) stream, with the
* platform default encoding.
*
* @throws IOException if there is an error while converting the stream
* to a string.
*/
public String getInputStreamAsString() throws IOException
{
byte[] bStream = getByteArray();
return new String(bStream);
}
/**
* Get the metadata that is part of the document catalog. This will
* return null if there is no meta data for this object.
*
* @return The metadata for this object.
*/
public PDMetadata getMetadata()
{
PDMetadata retval = null;
COSStream mdStream = (COSStream)stream.getDictionaryObject( COSName.METADATA );
if( mdStream != null )
{
retval = new PDMetadata( mdStream );
}
return retval;
}
/**
* Set the metadata for this object. This can be null.
*
* @param meta The meta data for this object.
*/
public void setMetadata( PDMetadata meta )
{
stream.setItem( COSName.METADATA, meta );
}
/**
* Get the decoded stream length.
*
* @since Apache PDFBox 1.1.0
* @see <a href="https://issues.apache.org/jira/browse/PDFBOX-636">PDFBOX-636</a>
* @return the decoded stream length
*/
public int getDecodedStreamLength()
{
return this.stream.getInt(COSName.DL);
}
/**
* Set the decoded stream length.
*
* @since Apache PDFBox 1.1.0
* @see <a href="https://issues.apache.org/jira/browse/PDFBOX-636">PDFBOX-636</a>
* @param decodedStreamLength the decoded stream length
*/
public void setDecodedStreamLength(int decodedStreamLength)
{
this.stream.setInt(COSName.DL, decodedStreamLength);
}
}