Package org.jcsp.util.ints

Class InfiniteBufferInt

java.lang.Object
org.jcsp.util.ints.InfiniteBufferInt
All Implemented Interfaces:
Serializable, Cloneable, ChannelDataStoreInt
public class InfiniteBufferInt extends Object implements ChannelDataStoreInt, Serializable
This is used to create a buffered integer channel that always accepts and never loses any input.

Description

InfiniteBufferInt is an implementation of ChannelDataStoreInt that yields a FIFO buffered semantics for a channel. When empty, the channel blocks readers. However, its capacity is infinite (expanding to whatever is needed so far as the underlying memory system will permit). So, it never gets full and blocks a writer. See the static construction methods of Channel (Channel.one2oneInt(org.jcsp.util.ints.ChannelDataStoreInt) etc.).

The getState method returns EMPTY or NONEMPTYFULL, but never FULL.

An initial size for the buffer can be specified during construction.

See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private int[]
    buffer
    The storage for the buffered ints
    private int
    counter
    The number of ints stored in the InfiniteBufferInt
    private static final int
    DEFAULT_SIZE
    The default size of the buffer
    private int
    firstIndex
    The index of the oldest element (when counter > 0)
    private int
    initialSize
    The initial size of the buffer
    private int
    lastIndex
    The index of the next free element (when counter invalid input: '<' buffer.length)

    Fields inherited from interface org.jcsp.util.ints.ChannelDataStoreInt

    EMPTY, FULL, NONEMPTYFULL

  • Constructor Summary

    Constructors
    Constructor
    Description
    InfiniteBufferInt()
    Construct a new InfiniteBufferInt with the default size (of 8).
    InfiniteBufferInt(int initialSize)
    Construct a new InfiniteBufferInt with the specified initial size.

  • Method Summary

    Modifier and Type
    Method
    Description
    Object
    clone()
    Returns a new (and EMPTY) InfiniteBufferInt with the same creation parameters as this one.
    void
    endGet()
    Removes the oldest integer from the buffer.
    int
    get()
    Returns the oldest int from the InfiniteBufferInt and removes it.
    int
    getState()
    Returns the current state of the InfiniteBufferInt.
    void
    put(int value)
    Puts a new int into the InfiniteBufferInt.
    void
    removeAll()
     
    int
    startGet()
    Returns the oldest integer from the buffer but does not remove it.

    Methods inherited from class java.lang.Object

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

  • Field Details

    • DEFAULT_SIZE

      private static final int DEFAULT_SIZE
      The default size of the buffer
      See Also:

    • initialSize

      private int initialSize
      The initial size of the buffer

    • buffer

      private int[] buffer
      The storage for the buffered ints

    • counter

      private int counter
      The number of ints stored in the InfiniteBufferInt

    • firstIndex

      private int firstIndex
      The index of the oldest element (when counter > 0)

    • lastIndex

      private int lastIndex
      The index of the next free element (when counter invalid input: '<' buffer.length)

  • Constructor Details

    • InfiniteBufferInt

      public InfiniteBufferInt()
      Construct a new InfiniteBufferInt with the default size (of 8).

    • InfiniteBufferInt

      public InfiniteBufferInt(int initialSize)
      Construct a new InfiniteBufferInt with the specified initial size.
      Parameters:
      initialSize - the number of ints the InfiniteBufferInt can initially store.
      Throws:
      BufferIntSizeError - if initialSize is zero or negative. Note: no action should be taken to try/catch this exception - application code generating it is in error and needs correcting.

  • Method Details

    • get

      public int get()
      Returns the oldest int from the InfiniteBufferInt and removes it.

      Pre-condition: getState must not currently return EMPTY.

      Specified by:
      get in interface ChannelDataStoreInt
      Returns:
      the oldest int from the InfiniteBufferInt

    • startGet

      public int startGet()
      Returns the oldest integer from the buffer but does not remove it. Pre-condition: getState must not currently return EMPTY.
      Specified by:
      startGet in interface ChannelDataStoreInt
      Returns:
      the oldest int from the Buffer
      See Also:

    • endGet

      public void endGet()
      Removes the oldest integer from the buffer.
      Specified by:
      endGet in interface ChannelDataStoreInt
      See Also:

    • put

      public void put(int value)
      Puts a new int into the InfiniteBufferInt.

      Implementation note: if InfiniteBufferInt is full, a new internal buffer with double the capacity is constructed and the old data copied across.

      Specified by:
      put in interface ChannelDataStoreInt
      Parameters:
      value - the int to put into the InfiniteBufferInt

    • getState

      public int getState()
      Returns the current state of the InfiniteBufferInt.
      Specified by:
      getState in interface ChannelDataStoreInt
      Returns:
      the current state of the InfiniteBufferInt (EMPTY or NONEMPTYFULL)

    • clone

      public Object clone()
      Returns a new (and EMPTY) InfiniteBufferInt with the same creation parameters as this one.

      Note: Only the initial size and structure of the InfiniteBufferInt is cloned, not any stored data.

      Specified by:
      clone in interface ChannelDataStoreInt
      Overrides:
      clone in class Object
      Returns:
      the cloned instance of this InfiniteBufferInt.

    • removeAll

      public void removeAll()
      Specified by:
      removeAll in interface ChannelDataStoreInt