Package com.Ostermiller.util

Class CircularByteBuffer

java.lang.Object
com.Ostermiller.util.CircularByteBuffer
public class CircularByteBuffer extends Object
Implements the Circular Buffer producer/consumer model for bytes. More information about this class is available from ostermiller.org.

Using this class is a simpler alternative to using a PipedInputStream and a PipedOutputStream. PipedInputStreams and PipedOutputStreams don't support the mark operation, don't allow you to control buffer sizes that they use, and have a more complicated API that requires instantiating two classes and connecting them.

This class is thread safe.

Since:
ostermillerutils 1.00.00
Author:
Stephen Ostermiller https://ostermiller.org/contact.pl?regarding=Java+Utilities
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    INFINITE_SIZE
    A buffer that will grow as things are added.

  • Constructor Summary

    Constructors
    Constructor
    Description
    CircularByteBuffer()
    Create a new buffer with a default capacity.
    CircularByteBuffer(boolean blockingWrite)
    Create a new buffer with a default capacity and given blocking behavior.
    CircularByteBuffer(int size)
    Create a new buffer with given capacity.
    CircularByteBuffer(int size, boolean blockingWrite)
    Create a new buffer with the given capacity and blocking behavior.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    clear()
    Make this buffer ready for reuse.
    int
    getAvailable()
    Get number of bytes that are available to be read.
    InputStream
    getInputStream()
    Retrieve a InputStream that can be used to empty this buffer.
    OutputStream
    getOutputStream()
    Retrieve a OutputStream that can be used to fill this buffer.
    int
    getSize()
    Get the capacity of this buffer.
    int
    getSpaceLeft()
    Get the number of bytes this buffer has free for writing.

    Methods inherited from class java.lang.Object

    equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • INFINITE_SIZE

      public static final int INFINITE_SIZE
      A buffer that will grow as things are added.
      Since:
      ostermillerutils 1.00.00
      See Also:

  • Constructor Details

    • CircularByteBuffer

      public CircularByteBuffer()
      Create a new buffer with a default capacity. Writing to a full buffer will block until space is available rather than throw an exception.
      Since:
      ostermillerutils 1.00.00

    • CircularByteBuffer

      public CircularByteBuffer(int size)
      Create a new buffer with given capacity. Writing to a full buffer will block until space is available rather than throw an exception.

      Note that the buffer may reserve some bytes for special purposes and capacity number of bytes may not be able to be written to the buffer.

      Note that if the buffer is of INFINITE_SIZE it will neither block or throw exceptions, but rather grow without bound.

      Parameters:
      size - desired capacity of the buffer in bytes or CircularByteBuffer.INFINITE_SIZE.
      Since:
      ostermillerutils 1.00.00

    • CircularByteBuffer

      public CircularByteBuffer(boolean blockingWrite)
      Create a new buffer with a default capacity and given blocking behavior.
      Parameters:
      blockingWrite - true writing to a full buffer should block until space is available, false if an exception should be thrown instead.
      Since:
      ostermillerutils 1.00.00

    • CircularByteBuffer

      public CircularByteBuffer(int size, boolean blockingWrite)
      Create a new buffer with the given capacity and blocking behavior.

      Note that the buffer may reserve some bytes for special purposes and capacity number of bytes may not be able to be written to the buffer.

      Note that if the buffer is of INFINITE_SIZE it will neither block or throw exceptions, but rather grow without bound.

      Parameters:
      size - desired capacity of the buffer in bytes or CircularByteBuffer.INFINITE_SIZE.
      blockingWrite - true writing to a full buffer should block until space is available, false if an exception should be thrown instead.
      Since:
      ostermillerutils 1.00.00

  • Method Details

    • clear

      public void clear()
      Make this buffer ready for reuse. The contents of the buffer will be cleared and the streams associated with this buffer will be reopened if they had been closed.
      Since:
      ostermillerutils 1.00.00

    • getOutputStream

      public OutputStream getOutputStream()
      Retrieve a OutputStream that can be used to fill this buffer.

      Write methods may throw a BufferOverflowException if the buffer is not large enough. A large enough buffer size must be chosen so that this does not happen or the caller must be prepared to catch the exception and try again once part of the buffer has been consumed.

      Returns:
      the producer for this buffer.
      Since:
      ostermillerutils 1.00.00

    • getInputStream

      public InputStream getInputStream()
      Retrieve a InputStream that can be used to empty this buffer.

      This InputStream supports marks at the expense of the buffer size.

      Returns:
      the consumer for this buffer.
      Since:
      ostermillerutils 1.00.00

    • getAvailable

      public int getAvailable()
      Get number of bytes that are available to be read.

      Note that the number of bytes available plus the number of bytes free may not add up to the capacity of this buffer, as the buffer may reserve some space for other purposes.

      Returns:
      the size in bytes of this buffer
      Since:
      ostermillerutils 1.00.00

    • getSpaceLeft

      public int getSpaceLeft()
      Get the number of bytes this buffer has free for writing.

      Note that the number of bytes available plus the number of bytes free may not add up to the capacity of this buffer, as the buffer may reserve some space for other purposes.

      Returns:
      the available space in bytes of this buffer
      Since:
      ostermillerutils 1.00.00

    • getSize

      public int getSize()
      Get the capacity of this buffer.

      Note that the number of bytes available plus the number of bytes free may not add up to the capacity of this buffer, as the buffer may reserve some space for other purposes.

      Returns:
      the size in bytes of this buffer
      Since:
      ostermillerutils 1.00.00