org.bibalex.daf.handlers.filehandler
Class FTPThreadsPool

java.lang.Object
  org.bibalex.daf.handlers.filehandler.FTPThreadsPool

 class FTPThreadsPool
extends java.lang.Object

A pool of FTP Threads, maintaining a fixed number of connections to the server an reducing the cost of recreating threads. This class is a Singlton (Only one instance can be instantiated).

Author:

Fadi.Edward

Field Summary

private static FTPThreadsPool	currentInstance
private java.util.Hashtable<java.lang.String,FTPThread>	freeThreads
private java.lang.String	hostName
private FileHandlerObservable	observable
private java.lang.String	password
private int	poolSize
private java.util.Hashtable<java.lang.String,FTPThread>	usedThreads
private java.lang.String	userName

Constructor Summary

private	FTPThreadsPool(java.lang.String hostName, java.lang.String userName, java.lang.String password, int poolSize) Private Constructor, preventing any external instantiation of new objects.
private	FTPThreadsPool(java.lang.String hostName, java.lang.String userName, java.lang.String password, int poolSize, FileHandlerObservable observable) Private Constructor, preventing any external instantiation of new objects.

Method Summary

private FTPThread	createThread() Create a new Thread.
void	finalize() Releases all used threads.
(package private) FTPThread	getThread() Retreives a thread, if there exists free threads one of them is returned, if not and the pool size wasn't reached a new thread is created, elsewise this method sends a wait() signal and halts.
static FTPThreadsPool	getThreadsPool(java.lang.String hostName, java.lang.String userName, java.lang.String password, int poolSize) Implementing a Singleton pattern in retrieving the instance of the Class.
static FTPThreadsPool	getThreadsPool(java.lang.String hostName, java.lang.String userName, java.lang.String password, int poolSize, FileHandlerObservable observable) Implementing a Singleton pattern in retrieving the instance of the Class.
void	releaseThread(FTPThread threadCopier) Release a thread to be returned to the Free Threads Hash.

Methods inherited from class java.lang.Object

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

Field Detail

hostName

private java.lang.String hostName

userName

private java.lang.String userName

password

private java.lang.String password

poolSize

private int poolSize

usedThreads

private java.util.Hashtable<java.lang.String,FTPThread> usedThreads

freeThreads

private java.util.Hashtable<java.lang.String,FTPThread> freeThreads

currentInstance

private static FTPThreadsPool currentInstance

observable

private FileHandlerObservable observable

Constructor Detail

FTPThreadsPool

private FTPThreadsPool(java.lang.String hostName,
                       java.lang.String userName,
                       java.lang.String password,
                       int poolSize)

Private Constructor, preventing any external instantiation of new objects.

Parameters:

hostName - Host Network Name or IP.

userName - User Name.

password - Password.

poolSize - Pool Size.

FTPThreadsPool

private FTPThreadsPool(java.lang.String hostName,
                       java.lang.String userName,
                       java.lang.String password,
                       int poolSize,
                       FileHandlerObservable observable)

Private Constructor, preventing any external instantiation of new objects.

Parameters:

hostName - Host Network Name or IP.

userName - User Name.

password - Password.

poolSize - Pool Size.

observable - FileHandlerObservable object to be assigned to the threads

Method Detail

getThreadsPool

public static FTPThreadsPool getThreadsPool(java.lang.String hostName,
                                            java.lang.String userName,
                                            java.lang.String password,
                                            int poolSize)

Implementing a Singleton pattern in retrieving the instance of the Class.

Parameters:

hostName - Host Network Name or IP.

userName - User Name.

password - Password.

poolSize - Pool Size.

Returns:

The FTPThreadsPool instance.

getThreadsPool

public static FTPThreadsPool getThreadsPool(java.lang.String hostName,
                                            java.lang.String userName,
                                            java.lang.String password,
                                            int poolSize,
                                            FileHandlerObservable observable)

Implementing a Singleton pattern in retrieving the instance of the Class.

Parameters:

hostName - Host Network Name or IP.

userName - User Name.

password - Password.

poolSize - Pool Size.

observable - FileHandlerObservable object to be assigned to the threads

Returns:

The FTPThreadsPool instance.

finalize

public void finalize()

Releases all used threads.

Overrides:

finalize in class java.lang.Object

releaseThread

public void releaseThread(FTPThread threadCopier)

Release a thread to be returned to the Free Threads Hash.

Parameters:

threadCopier - The thread to be freed.

createThread

private FTPThread createThread()

Create a new Thread. This method is only called when the pool size wasn't reached and there is no free threads.

Returns:

an FTPThread thread.

getThread

FTPThread getThread()

Retreives a thread, if there exists free threads one of them is returned, if not and the pool size wasn't reached a new thread is created, elsewise this method sends a wait() signal and halts.

Returns:

an FTPThread instance.