Interface StreamHeaderGenerator

All Known Implementing Classes:
CharStreamHeaderGenerator, ClobStreamHeaderGenerator
public interface StreamHeaderGenerator
Generates stream headers encoding the length of the stream.

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    expectsCharCount()
    Tells if the header encodes a character or byte count.
    int
    generateInto(byte[] buf, int offset, long valueLength)
    Generates the header for the specified length and writes it into the provided buffer, starting at the specified offset.
    int
    generateInto(ObjectOutput out, long valueLength)
    Generates the header for the specified length and writes it into the destination stream.
    int
    getMaxHeaderLength()
    Returns the maximum length of the header.
    int
    writeEOF(byte[] buffer, int offset, long valueLength)
    Writes a Derby-specific end-of-stream marker to the buffer for a stream of the specified length, if required.
    int
    writeEOF(ObjectOutput out, long valueLength)
    Writes a Derby-specific end-of-stream marker to the destination stream for the specified length, if required.

  • Method Details

    • expectsCharCount

      boolean expectsCharCount()
      Tells if the header encodes a character or byte count.
      Returns:
      true if the character count is encoded into the header, false if the byte count is encoded into the header.

    • generateInto

      int generateInto(byte[] buf, int offset, long valueLength)
      Generates the header for the specified length and writes it into the provided buffer, starting at the specified offset.
      Parameters:
      buf - the buffer to write into
      offset - starting offset in the buffer
      valueLength - the length of the stream, can be in either bytes or characters depending on the header format
      Returns:
      The number of bytes written into the buffer.

    • generateInto

      int generateInto(ObjectOutput out, long valueLength) throws IOException
      Generates the header for the specified length and writes it into the destination stream.
      Parameters:
      out - the destination stream
      valueLength - the length of the stream, can be in either bytes or characters depending on the header format
      Returns:
      The number of bytes written to the destination stream.
      Throws:
      IOException - if writing to the destination stream fails

    • writeEOF

      int writeEOF(byte[] buffer, int offset, long valueLength)
      Writes a Derby-specific end-of-stream marker to the buffer for a stream of the specified length, if required.
      Parameters:
      buffer - the buffer to write into
      offset - starting offset in the buffer
      valueLength - the length of the stream, can be in either bytes or characters depending on the header format
      Returns:
      Number of bytes written (zero or more).

    • writeEOF

      int writeEOF(ObjectOutput out, long valueLength) throws IOException
      Writes a Derby-specific end-of-stream marker to the destination stream for the specified length, if required.
      Parameters:
      out - the destination stream
      valueLength - the length of the stream, can be in either bytes or characters depending on the header format
      Returns:
      Number of bytes written (zero or more).
      Throws:
      IOException - if writing to the destination stream fails

    • getMaxHeaderLength

      int getMaxHeaderLength()
      Returns the maximum length of the header.
      Returns:
      Max header length in bytes.