com.revolsys.parallel.channel.store

Class Buffer<T>

java.lang.Object

com.revolsys.parallel.channel.ChannelValueStore<T>

com.revolsys.parallel.channel.store.Buffer<T>

All Implemented Interfaces:

Cloneable

public class Buffer<T>
extends ChannelValueStore<T>

Description

The Buffer class is an implementation of ChannelValueStore which allows more than one Object to be sent across the Channel at any one time. The Buffer will store the Objects and allow them to be read in the same order as they were written.

The getState method will return EMPTY if the Channel does not contain any Objects, FULL if it cannot accept more data and NONEMPTYFULL otherwise.

Author:

P.D.Austin

Field Summary

Fields inherited from class com.revolsys.parallel.channel.ChannelValueStore

EMPTY, FULL, NONEMPTYFULL

Constructor Summary

Constructors

Constructor and Description
Buffer() Construct a new Buffer with no maximum size.
Buffer(int maxSize) Construct a new Buffer with the specified maximum size.
Buffer(Queue<T> buffer) Construct a new Buffer with the no maximum size.
Buffer(Queue<T> buffer, int maxSize) Construct a new Buffer with the specified maximum size.

Method Summary

Methods

Modifier and Type	Method and Description
void	clear() Empty the buffer.
protected Object	clone() Returns a new Object with the same creation parameters as this Object.
protected T	get() Returns the first Object from the Buffer and removes the Object from the Buffer.
protected int	getState() Returns the current state of the Buffer, should be called to ensure the Pre-conditions of the other methods are not broken.
protected void	put(T value) Puts a new Object into the Buffer.
boolean	remove(T object) Remove the object from the buffer.
int	size() The number of items in the buffer.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Buffer

public Buffer()

Construct a new Buffer with no maximum size.

Buffer

public Buffer(int maxSize)

Construct a new Buffer with the specified maximum size.

Parameters:

maxSize - The maximum number of Objects the Buffer can store

Buffer

public Buffer(Queue<T> buffer)

Construct a new Buffer with the no maximum size.

Parameters:

buffer - The buffer to store the elements in.

Buffer

public Buffer(Queue<T> buffer,
      int maxSize)

Construct a new Buffer with the specified maximum size.

Parameters:

buffer - The buffer to store the elements in.

size - The maximum number of Objects the Buffer can store

Method Detail

clear

public void clear()

Empty the buffer.

clone

protected Object clone()

Returns a new Object with the same creation parameters as this Object. This method should be overridden by subclasses to return a new Object that is the same type as this Object. The new instance should be created by constructing a new instance with the same parameters as the original. NOTE: Only the sizes of the data should be cloned not the stored data.

Specified by:

clone in class ChannelValueStore<T>

Returns:

The cloned instance of this Object.

get

protected T get()

Returns the first Object from the Buffer and removes the Object from the Buffer.

NOTE: getState should be called before this method to check that the state is not EMPTY. If the state is EMPTY the Buffer will be left in an undefined state.

Pre-condition: The state must not be EMPTY

Specified by:

get in class ChannelValueStore<T>

Returns:

The next available Object from the Buffer

getState

protected int getState()

Returns the current state of the Buffer, should be called to ensure the Pre-conditions of the other methods are not broken.

Specified by:

getState in class ChannelValueStore<T>

Returns:

The current state of the Buffer (EMPTY, NONEMPTYFULL or FULL)

put

protected void put(T value)

Puts a new Object into the Buffer.

NOTE: getState should be called before this method to check that the state is not FULL. If the state is FULL the Buffer will be left in an undefined state.

Pre-condition: The state must not be FULL

Specified by:

put in class ChannelValueStore<T>

Parameters:

value - The object to put in the Buffer

remove

public boolean remove(T object)

Remove the object from the buffer.

Parameters:

object - The object to remove.

Returns:

True if the object was removed.

size

public int size()

The number of items in the buffer.

Returns:

The number of items in the buffer.

toString

public String toString()

Overrides:

toString in class Object