Package org.apache.pdfbox.cos

Class COSStream

java.lang.Object

org.apache.pdfbox.cos.COSBase

org.apache.pdfbox.cos.COSDictionary

org.apache.pdfbox.cos.COSStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, COSUpdateInfo, COSObjectable

public class COSStream
extends COSDictionary
implements java.io.Closeable

This class represents a stream object in a PDF document.

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	closeStreamCache
private boolean	isWriting
private static org.apache.commons.logging.Log	LOG
private RandomAccess	randomAccess
private RandomAccessReadView	randomAccessReadView
private RandomAccessStreamCache	streamCache

Fields inherited from class org.apache.pdfbox.cos.COSDictionary

items

Constructor Summary

Constructors

Constructor	Description
COSStream()	Creates a new stream with an empty dictionary.
COSStream(RandomAccessStreamCache streamCache)	Creates a new stream with an empty dictionary.
COSStream(RandomAccessStreamCache streamCache, RandomAccessReadView randomAccessReadView)	Creates a new stream with an empty dictionary.

Method Summary

Modifier and Type	Method	Description
void	accept(ICOSVisitor visitor)	visitor pattern double dispatch method.
private void	checkClosed()	Throws if the random access backing store has been closed.
void	close()	Called by PDFBox when the PDDocument is closed, this closes the stream and removes the data.
COSInputStream	createInputStream()	Returns a new InputStream which reads the decoded stream data.
COSInputStream	createInputStream(DecodeOptions options)
java.io.OutputStream	createOutputStream()	Returns a new OutputStream for writing stream data, using the current filters.
java.io.OutputStream	createOutputStream(COSBase filters)	Returns a new OutputStream for writing stream data, using and the given filters.
java.io.InputStream	createRawInputStream()	Returns a new InputStream which reads the encoded PDF stream data.
java.io.OutputStream	createRawOutputStream()	Returns a new OutputStream for writing encoded PDF data.
RandomAccessRead	createView()	Returns a new RandomAccessRead which reads the decoded stream data.
private java.util.List<Filter>	getFilterList()	Returns the list of filters.
COSBase	getFilters()	This will return the filters to apply to the byte stream.
long	getLength()	Returns the length of the encoded stream.
private RandomAccessStreamCache	getStreamCache()
boolean	hasData()	Indicates whether the stream contains any data or not.
java.lang.String	toTextString()	Returns the contents of the stream as a PDF "text string".

Methods inherited from class org.apache.pdfbox.cos.COSDictionary

addAll, asUnmodifiableDictionary, clear, containsKey, containsKey, containsValue, entrySet, forEach, getBoolean, getBoolean, getBoolean, getCOSArray, getCOSDictionary, getCOSDictionary, getCOSName, getCOSName, getCOSObject, getCOSStream, getDate, getDate, getDate, getDate, getDictionaryObject, getDictionaryObject, getDictionaryObject, getEmbeddedDate, getEmbeddedDate, getEmbeddedInt, getEmbeddedInt, getEmbeddedString, getEmbeddedString, getFlag, getFloat, getFloat, getFloat, getFloat, getIndirectObjectKeys, getIndirectObjectKeys, getInt, getInt, getInt, getInt, getInt, getInt, getItem, getItem, getItem, getKeyForValue, getLong, getLong, getLong, getLong, getNameAsString, getNameAsString, getNameAsString, getNameAsString, getObjectFromPath, getString, getString, getString, getString, getUpdateState, getValues, keySet, removeItem, setBoolean, setBoolean, setDate, setDate, setEmbeddedDate, setEmbeddedInt, setEmbeddedString, setFlag, setFloat, setFloat, setInt, setInt, setItem, setItem, setItem, setItem, setLong, setLong, setName, setName, setString, setString, size, toString

Methods inherited from class org.apache.pdfbox.cos.COSBase

getCOSObject, getKey, isDirect, setDirect, setKey

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.pdfbox.pdmodel.common.COSObjectable

getCOSObject

Methods inherited from interface org.apache.pdfbox.cos.COSUpdateInfo

isNeedToBeUpdated, setNeedToBeUpdated, toIncrement

Field Detail

randomAccess

private RandomAccess randomAccess

streamCache

private RandomAccessStreamCache streamCache

closeStreamCache

private boolean closeStreamCache

isWriting

private boolean isWriting

randomAccessReadView

private RandomAccessReadView randomAccessReadView

LOG

private static final org.apache.commons.logging.Log LOG

Constructor Detail

COSStream

public COSStream()

Creates a new stream with an empty dictionary.

Try to avoid using this constructor because it creates a new scratch file in memory. Instead, use document.getDocument().createCOSStream() which will use the existing scratch file (in memory or in temp file) of the document.

COSStream

public COSStream(RandomAccessStreamCache streamCache)

Creates a new stream with an empty dictionary. Data is stored in the given scratch file.

Parameters:

streamCache - Stream cache for writing stream data.

COSStream

public COSStream(RandomAccessStreamCache streamCache,
                 RandomAccessReadView randomAccessReadView)
          throws java.io.IOException

Creates a new stream with an empty dictionary. Data is read from the given random accessview. Written data is stored in the given scratch file.

Parameters:

streamCache - Stream cache for writing stream data.

randomAccessReadView - source for the data to be read

Throws:

java.io.IOException - if the length of the random access view isn't available

Method Detail

checkClosed

private void checkClosed()
                  throws java.io.IOException

Throws if the random access backing store has been closed. Helpful for catching cases where a user tries to use a COSStream which has outlived its COSDocument.

Throws:

java.io.IOException

getStreamCache

private RandomAccessStreamCache getStreamCache()
                                        throws java.io.IOException

Throws:

java.io.IOException

createRawInputStream

public java.io.InputStream createRawInputStream()
                                         throws java.io.IOException

Returns a new InputStream which reads the encoded PDF stream data. Experts only!

Returns:

InputStream containing raw, encoded PDF stream data.

Throws:

java.io.IOException - If the stream could not be read.

createInputStream

public COSInputStream createInputStream()
                                 throws java.io.IOException

Returns a new InputStream which reads the decoded stream data.

Returns:

InputStream containing decoded stream data.

Throws:

java.io.IOException - If the stream could not be read.

createInputStream

public COSInputStream createInputStream(DecodeOptions options)
                                 throws java.io.IOException

Throws:

java.io.IOException

createView

public RandomAccessRead createView()
                            throws java.io.IOException

Returns a new RandomAccessRead which reads the decoded stream data.

Returns:

RandomAccessRead containing decoded stream data.

Throws:

java.io.IOException - If the stream could not be read.

createOutputStream

public java.io.OutputStream createOutputStream()
                                        throws java.io.IOException

Returns a new OutputStream for writing stream data, using the current filters.

Returns:

OutputStream for un-encoded stream data.

Throws:

java.io.IOException - If the output stream could not be created.

createOutputStream

public java.io.OutputStream createOutputStream(COSBase filters)
                                        throws java.io.IOException

Returns a new OutputStream for writing stream data, using and the given filters.

Parameters:

filters - COSArray or COSName of filters to be used.

Returns:

OutputStream for un-encoded stream data.

Throws:

java.io.IOException - If the output stream could not be created.

createRawOutputStream

public java.io.OutputStream createRawOutputStream()
                                           throws java.io.IOException

Returns a new OutputStream for writing encoded PDF data. Experts only!

Returns:

OutputStream for raw PDF stream data.

Throws:

java.io.IOException - If the output stream could not be created.

getFilterList

private java.util.List<Filter> getFilterList()
                                      throws java.io.IOException

Returns the list of filters.

Throws:

java.io.IOException

getLength

public long getLength()

Returns the length of the encoded stream.

Returns:

length in bytes

getFilters

public COSBase getFilters()

This will return the filters to apply to the byte stream. The method will return

• null if no filters are to be applied
• a COSName if one filter is to be applied
• a COSArray containing COSNames if multiple filters are to be applied

Returns:

the COSBase object representing the filters

toTextString

public java.lang.String toTextString()

Returns the contents of the stream as a PDF "text string".

Returns:

the PDF string representation of the stream content

accept

public void accept(ICOSVisitor visitor)
            throws java.io.IOException

Description copied from class: COSDictionary

visitor pattern double dispatch method.

Overrides:

accept in class COSDictionary

Parameters:

visitor - The object to notify when visiting this object.

Throws:

java.io.IOException - If there is an error visiting this object.

close

public void close()
           throws java.io.IOException

Called by PDFBox when the PDDocument is closed, this closes the stream and removes the data. You will usually not need this.

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Throws:

java.io.IOException - if something went wrong when closing the stream

hasData

public boolean hasData()

Indicates whether the stream contains any data or not.

Returns:

true if the stream contains any data