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:
Closeable, AutoCloseable, COSUpdateInfo, COSObjectable
public class COSStream extends COSDictionary implements Closeable
This class represents a stream object in a PDF document.

  • Field Details

    • 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 Details

    • 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 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:
      IOException - if the length of the random access view isn't available

  • Method Details

    • checkClosed

      private void checkClosed() throws 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:
      IOException

    • getStreamCache

      private RandomAccessStreamCache getStreamCache() throws IOException
      Throws:
      IOException

    • createRawInputStream

      public InputStream createRawInputStream() throws IOException
      Returns a new InputStream which reads the encoded PDF stream data. Experts only!
      Returns:
      InputStream containing raw, encoded PDF stream data.
      Throws:
      IOException - If the stream could not be read.

    • createInputStream

      public COSInputStream createInputStream() throws IOException
      Returns a new InputStream which reads the decoded stream data.
      Returns:
      InputStream containing decoded stream data.
      Throws:
      IOException - If the stream could not be read.

    • createInputStream

      public COSInputStream createInputStream(DecodeOptions options) throws IOException
      Throws:
      IOException

    • createView

      public RandomAccessRead createView() throws IOException
      Returns a new RandomAccessRead which reads the decoded stream data.
      Returns:
      RandomAccessRead containing decoded stream data.
      Throws:
      IOException - If the stream could not be read.

    • createOutputStream

      public OutputStream createOutputStream() throws IOException
      Returns a new OutputStream for writing stream data, using the current filters.
      Returns:
      OutputStream for un-encoded stream data.
      Throws:
      IOException - If the output stream could not be created.

    • createOutputStream

      public OutputStream createOutputStream(COSBase filters) throws 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:
      IOException - If the output stream could not be created.

    • createRawOutputStream

      public OutputStream createRawOutputStream() throws IOException
      Returns a new OutputStream for writing encoded PDF data. Experts only!
      Returns:
      OutputStream for raw PDF stream data.
      Throws:
      IOException - If the output stream could not be created.

    • getFilterList

      private List<Filter> getFilterList() throws IOException
      Returns the list of filters.
      Throws:
      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 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 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:
      IOException - If there is an error visiting this object.

    • close

      public void close() throws 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 AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      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