Class LayerBStreamedEXTDTAReaderInputStream

java.lang.Object
java.io.InputStream
org.apache.derby.impl.drda.EXTDTAReaderInputStream
org.apache.derby.impl.drda.LayerBStreamedEXTDTAReaderInputStream
All Implemented Interfaces:
Closeable, AutoCloseable

final class LayerBStreamedEXTDTAReaderInputStream extends EXTDTAReaderInputStream
Implementation of InputStream which get EXTDTA from the DDMReader. This class can be used to stream LOBs from Network client to the Network server. Furthermore, this class is used when layer B streaming is carried out and expects corresponding DDMReader start layer B streaming when the object of this class is instantiated.
  • Field Details

    • reader

      private final DDMReader reader
      DDMReader. Used to get more data.
    • currentBuffer

      private ByteArrayInputStream currentBuffer
      Current data buffer
  • Constructor Details

    • LayerBStreamedEXTDTAReaderInputStream

      LayerBStreamedEXTDTAReaderInputStream(DDMReader reader, boolean readStatusByte) throws DRDAProtocolException
      Constructor
      Parameters:
      reader - The reader to get data from
      readStatusByte - whether or not to read the trailing Derby-specific EXTDTA stream status byte
      Throws:
      DRDAProtocolException - if thrown while initializing current buffer.
  • Method Details

    • read

      public final int read() throws IOException
      Reads the next byte of data from the input stream.

      This subclass of InputStream implements this method by reading the next byte from the current buffer. If there is more data, it will be requested a new buffer from the DDMReader.

      Specified by:
      read in class InputStream
      Returns:
      the next byte of data, or -1 if the end of the stream is reached.
      Throws:
      IOException - if an I/O error occurs.
      See Also:
    • read

      public final int read(byte[] b, int off, int len) throws IOException
      Reads up to len bytes of data from the input stream into an array of bytes. An attempt is made to read as many as len bytes, but a smaller number may be read, possibly zero. The number of bytes actually read is returned as an integer. This subclass implements this method by calling this method on the current buffer, which is an instance of ByteArrayInputStream. If the current buffer does not have any data, it will be requested a new buffer from the DDMReader.
      Overrides:
      read in class InputStream
      Parameters:
      b - the buffer into which the data is read.
      off - the start offset in array b at which the data is written.
      len - the maximum number of bytes to read.
      Returns:
      the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
      Throws:
      IOException - if an I/O error occurs.
      NullPointerException - if b is null.
      See Also:
    • available

      public final int available()
      Returns the number of bytes that can be read (or skipped over) from this input stream without blocking by the next caller of a method for this input stream.

      This subclass implements this method by calling available on the current buffer, which is a ByteInputStreamReader.

      Overrides:
      available in class InputStream
      Returns:
      the number of bytes that can be read from this input stream without blocking.
    • onClientSideStreamingError

      protected void onClientSideStreamingError()
      Description copied from class: EXTDTAReaderInputStream
      Performs necessary clean up when an error is signalled by the client.
      Specified by:
      onClientSideStreamingError in class EXTDTAReaderInputStream