org.apache.pdfbox.pdmodel.common

Class PDStream

java.lang.Object

org.apache.pdfbox.pdmodel.common.PDStream

All Implemented Interfaces:

COSObjectable

Direct Known Subclasses:

PDEmbeddedFile, PDMemoryStream, PDMetadata, PDObjectStream

public class PDStream
extends Object
implements COSObjectable

A PDStream represents a stream in a PDF document. Streams are tied to a single PDF document.

Version:

$Revision: 1.17 $

Author:

Ben Litchfield

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PDStream() This will create a new PDStream object.
	PDStream(COSStream str) Constructor.
	PDStream(PDDocument document) This will create a new PDStream object.
	PDStream(PDDocument doc, InputStream str) Constructor.
	PDStream(PDDocument doc, InputStream str, boolean filtered) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	addCompression() If there are not compression filters on the current stream then this will add a compression filter, flate compression for example.
static PDStream	createFromCOS(COSBase base) Create a pd stream from either a regular COSStream on a COSArray of cos streams.
InputStream	createInputStream() This will get a stream that can be read from.
OutputStream	createOutputStream() This will get a stream that can be written to.
byte[]	getByteArray() This will copy the stream into a byte array.
COSBase	getCOSObject() Convert this standard java object to a COS object.
int	getDecodedStreamLength() Get the decoded stream length.
List<Object>	getDecodeParms() Get the list of decode parameters.
PDFileSpecification	getFile() This will get the file specification for this stream.
List<Object>	getFileDecodeParams() Get the list of decode parameters.
List<String>	getFileFilters() This will get the list of filters that are associated with this stream.
List<COSName>	getFilters() This will get the list of filters that are associated with this stream.
String	getInputStreamAsString() A convenience method to get this stream as a string.
int	getLength() This will get the length of the filtered/compressed stream.
PDMetadata	getMetadata() Get the metadata that is part of the document catalog.
InputStream	getPartiallyFilteredStream(List<String> stopFilters) This will get a stream with some filters applied but not others.
COSStream	getStream() Get the cos stream associated with this object.
void	setDecodedStreamLength(int decodedStreamLength) Set the decoded stream length.
void	setDecodeParms(List<?> decodeParams) This will set the list of decode parameterss.
void	setFile(PDFileSpecification f) Set the file specification.
void	setFileDecodeParams(List<?> decodeParams) This will set the list of decode params.
void	setFileFilters(List<String> filters) This will set the filters that are part of this stream.
void	setFilters(List<COSName> filters) This will set the filters that are part of this stream.
void	setMetadata(PDMetadata meta) Set the metadata for this object.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PDStream

protected PDStream()

This will create a new PDStream object.

PDStream

public PDStream(PDDocument document)

This will create a new PDStream object.

Parameters:

document - The document that the stream will be part of.

PDStream

public PDStream(COSStream str)

Constructor.

Parameters:

str - The stream parameter.

PDStream

public PDStream(PDDocument doc,
        InputStream str)
         throws IOException

Constructor. Reads all data from the input stream and embeds it into the document, this will close the InputStream.

Parameters:

doc - The document that will hold the stream.

str - The stream parameter.

Throws:

IOException - If there is an error creating the stream in the document.

PDStream

public PDStream(PDDocument doc,
        InputStream str,
        boolean filtered)
         throws IOException

Constructor. Reads all data from the input stream and embeds it into the document, this will close the InputStream.

Parameters:

doc - The document that will hold the stream.

str - The stream parameter.

filtered - True if the stream already has a filter applied.

Throws:

IOException - If there is an error creating the stream in the document.

Method Detail

addCompression

public void addCompression()

If there are not compression filters on the current stream then this will add a compression filter, flate compression for example.

createFromCOS

public static PDStream createFromCOS(COSBase base)
                              throws IOException

Create a pd stream from either a regular COSStream on a COSArray of cos streams.

Parameters:

base - Either a COSStream or COSArray.

Returns:

A PDStream or null if base is null.

Throws:

IOException - If there is an error creating the PDStream.

getCOSObject

public COSBase getCOSObject()

Convert this standard java object to a COS object.

Specified by:

getCOSObject in interface COSObjectable

Returns:

The cos object that matches this Java object.

createOutputStream

public OutputStream createOutputStream()
                                throws IOException

This will get a stream that can be written to.

Returns:

An output stream to write data to.

Throws:

IOException - If an IO error occurs during writing.

createInputStream

public InputStream createInputStream()
                              throws IOException

This will get a stream that can be read from.

Returns:

An input stream that can be read from.

Throws:

IOException - If an IO error occurs during reading.

getPartiallyFilteredStream

public InputStream getPartiallyFilteredStream(List<String> stopFilters)
                                       throws IOException

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

Parameters:

stopFilters - A list of filters to stop decoding at.

Returns:

A stream with decoded data.

Throws:

IOException - If there is an error processing the stream.

getStream

public COSStream getStream()

Get the cos stream associated with this object.

Returns:

The cos object that matches this Java object.

getLength

public int getLength()

This will get the length of the filtered/compressed stream. This is readonly in the PD Model and will be managed by this class.

Returns:

The length of the filtered stream.

getFilters

public List<COSName> getFilters()

This will get the list of filters that are associated with this stream. Or null if there are none.

Returns:

A list of all encoding filters to apply to this stream.

setFilters

public void setFilters(List<COSName> filters)

This will set the filters that are part of this stream.

Parameters:

filters - The filters that are part of this stream.

getDecodeParms

public List<Object> getDecodeParms()
                            throws IOException

Get the list of decode parameters. Each entry in the list will refer to an entry in the filters list.

Returns:

The list of decode parameters.

Throws:

IOException - if there is an error retrieving the parameters.

setDecodeParms

public void setDecodeParms(List<?> decodeParams)

This will set the list of decode parameterss.

Parameters:

decodeParams - The list of decode parameterss.

getFile

public PDFileSpecification getFile()
                            throws IOException

This will get the file specification for this stream. This is only required for external files.

Returns:

The file specification.

Throws:

IOException - If there is an error creating the file spec.

setFile

public void setFile(PDFileSpecification f)

Set the file specification.

Parameters:

f - The file specification.

getFileFilters

public List<String> getFileFilters()

This will get the list of filters that are associated with this stream. Or null if there are none.

Returns:

A list of all encoding filters to apply to this stream.

setFileFilters

public void setFileFilters(List<String> filters)

This will set the filters that are part of this stream.

Parameters:

filters - The filters that are part of this stream.

getFileDecodeParams

public List<Object> getFileDecodeParams()
                                 throws IOException

Get the list of decode parameters. Each entry in the list will refer to an entry in the filters list.

Returns:

The list of decode parameters.

Throws:

IOException - if there is an error retrieving the parameters.

setFileDecodeParams

public void setFileDecodeParams(List<?> decodeParams)

This will set the list of decode params.

Parameters:

decodeParams - The list of decode params.

getByteArray

public byte[] getByteArray()
                    throws IOException

This will copy the stream into a byte array.

Returns:

The byte array of the filteredStream

Throws:

IOException - When getFilteredStream did not work

getInputStreamAsString

public String getInputStreamAsString()
                              throws IOException

A convenience method to get this stream as a string. Uses the default system encoding.

Returns:

a String representation of this (input) stream.

Throws:

IOException - if there is an error while converting the stream to a string.

getMetadata

public PDMetadata getMetadata()

Get the metadata that is part of the document catalog. This will return null if there is no meta data for this object.

Returns:

The metadata for this object.

Throws:

IllegalStateException - if the value of the metadata entry is different from a stream or null

setMetadata

public void setMetadata(PDMetadata meta)

Set the metadata for this object. This can be null.

Parameters:

meta - The meta data for this object.

getDecodedStreamLength

public int getDecodedStreamLength()

Get the decoded stream length.

Returns:

the decoded stream length

Since:

Apache PDFBox 1.1.0

See Also:

PDFBOX-636

setDecodedStreamLength

public void setDecodedStreamLength(int decodedStreamLength)

Set the decoded stream length.

Parameters:

decodedStreamLength - the decoded stream length

Since:

Apache PDFBox 1.1.0

See Also:

PDFBOX-636