Class WrappedOutputStream

java.lang.Object
java.io.OutputStream
java.io.FilterOutputStream
cardmanager.impl.networking.WrappedOutputStream
All Implemented Interfaces:
Closeable, Flushable, AutoCloseable

public class WrappedOutputStream extends FilterOutputStream
This output stream works in conjunction with the WrappedInputStream to introduce a protocol for sending arbitrary length data in a uniform way. This output stream allows variable length data to be inserted into an existing output stream so that it can be read by an input stream without reading too many bytes (in case of buffering by the input stream).

This output stream is used like any normal output stream. The protocol is introduced by the WrappedOutputStream and does not need to be known by the user of this class. However, for those that are interested, the method is described below.

The output stream writes the requested bytes as packets of binary information. The packet consists of a header and payload. The header is two bytes of a single unsigned short (written in network order) that specifies the length of bytes in the payload. A header value of 0 indicates that the stream is "closed".

Note: For this wrapped output stream to be used, the application must call close() to end the output.

See Also:
  • Field Details

    • DEFAULT_BUFFER_SIZE

      public static final int DEFAULT_BUFFER_SIZE
      Default buffer size (1024).
      See Also:
    • fBuffer

      protected byte[] fBuffer
      Buffer.
    • fPosition

      protected int fPosition
      Buffer position.
    • fDataOutputStream

      protected DataOutputStream fDataOutputStream
      Data output stream. This stream is used to output the block sizes into the data stream that are read by the WrappedInputStream.

      Note: The data output stream is only used for writing the byte count for performance reasons. We avoid the method indirection for writing the byte data.

  • Constructor Details

    • WrappedOutputStream

      public WrappedOutputStream(OutputStream stream)
      Constructs a wrapper for the given output stream.
    • WrappedOutputStream

      public WrappedOutputStream(OutputStream stream, int bufferSize)
      Constructs a wrapper for the given output stream with the given buffer size.
  • Method Details

    • write

      public void write(int b) throws IOException
      Writes a single byte to the output.

      Note: Single bytes written to the output stream will be buffered

      Overrides:
      write in class FilterOutputStream
      Throws:
      IOException
    • write

      public void write(byte[] b, int offset, int length) throws IOException
      Writes an array of bytes to the output.
      Overrides:
      write in class FilterOutputStream
      Throws:
      IOException
    • flush

      public void flush() throws IOException
      Flushes the output buffer, writing all bytes currently in the buffer to the output.
      Specified by:
      flush in interface Flushable
      Overrides:
      flush in class FilterOutputStream
      Throws:
      IOException
    • close

      public void close() throws IOException
      Closes the output stream. This method must be called when done writing all data to the output stream.

      Note: This method does not close the actual output stream, only makes the input stream see the stream closed. Do not write bytes after closing the output stream.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class FilterOutputStream
      Throws:
      IOException
    • flush0

      public void flush0() throws IOException
      Flushes the output buffer, writing all bytes currently in the buffer to the output. This method does not call the flush() method of the output stream; it merely writes the remaining bytes in the buffer.
      Throws:
      IOException