com.antelmann.db.remote
Class ChangeNotificationClient

java.lang.Object
  com.antelmann.db.remote.ChangeNotificationClient

All Implemented Interfaces:

Closeable

public class ChangeNotificationClient
extends Object
implements Closeable

provides an easy mechanism to setup a client for change notification on a database.

Since:

16.11.2008, 16:39:08

Author:

holger Antelmann

See Also:

ChangeNotificationServer, RemoteDBChangeNotifier, RemoteDatabaseChangeHandler

Constructor Summary

ChangeNotificationClient(NetConnection con, Database<?> db, boolean deliverChanges)
starts a client daemon thread that listens to changes; if deliverChanges is true, this client also propagates changes from the database to the server using a notifier.

ChangeNotificationClient(String databaseName, Database<?> db, String server, boolean deliverChanges)

ChangeNotificationClient(String databaseName, Database<?> db, String server, int port, boolean deliverChanges)
creates a SocketConnection to the server based on the given parameters and calls the constructor that takes a NetConnection

Method Summary

void	addListener(DatabaseChangeListener l) convenience method; delegates to the monitor
void	close() stops/closes both, notifier and handler; removes all listeners and sets all member variables to null
protected void	finalize()
MessageDelegator	getDelegator() returns the delegator that uses the RemoteDatabaseChangeHandler, which has been started in its own daemon thread at construction time
Thread	getDelegatorThread() returns the thread that runs the delegator
RemoteDatabaseChangeHandler	getHandler()
RemoteDBChangeNotifier	getNotifier() this is non-null only if this instance was created with deliverChanges set to true
boolean	removeListener(DatabaseChangeListener l) convenience method; delegates to the monitor
void	setNotificationFilter(RemoteDBChangeFilter filter)

Methods inherited from class java.lang.Object

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

Constructor Detail

ChangeNotificationClient

public ChangeNotificationClient(String databaseName,
                                Database<?> db,
                                String server,
                                boolean deliverChanges)
                         throws IOException

Throws:

IOException

ChangeNotificationClient

public ChangeNotificationClient(String databaseName,
                                Database<?> db,
                                String server,
                                int port,
                                boolean deliverChanges)
                         throws IOException

creates a SocketConnection to the server based on the given parameters and calls the constructor that takes a NetConnection

Parameters:

databaseName - the name of the database that must correspond to the database name used by the ChangeNotificationServer

db - the database used to deliver the RemoteDBUpdateEvent instances

server - the host that runs the ChangeNotificationServer

port - the port on which the server runs

deliverChanges - if set to true, a DatabaseChangeMonitor is deployed to propagate changes from the given database to the server for notification.

Throws:

IOException

ChangeNotificationClient

public ChangeNotificationClient(NetConnection con,
                                Database<?> db,
                                boolean deliverChanges)
                         throws IOException

starts a client daemon thread that listens to changes; if deliverChanges is true, this client also propagates changes from the database to the server using a notifier. The handler is run by a MessageDelegator in a daemon thread. The notifier (a RemoteDBChangeNotifier) is enabled through a DatabaseChangeMonitor instance if applicable. Note that if this also client delivers changes, it will receive updates only if the server is set to send notifications to the same connection that delivered it.

Parameters:

con - the connection to the ChangeNotificationServer

db - the database used to deliver the RemoteDBUpdateEvent instances

deliverChanges - if set to true, a DatabaseChangeMonitor is deployed to propagate changes from the given database to the server for notification.

Throws:

IOException

See Also:

ChangeNotificationServer.setDeliverToSelf(boolean), DatabaseChangeMonitor

Method Detail

setNotificationFilter

public void setNotificationFilter(RemoteDBChangeFilter filter)
                           throws IOException

Throws:

IOException

getNotifier

public RemoteDBChangeNotifier getNotifier()

this is non-null only if this instance was created with deliverChanges set to true

getDelegatorThread

public Thread getDelegatorThread()

returns the thread that runs the delegator

See Also:

getDelegator()

getHandler

public RemoteDatabaseChangeHandler getHandler()

getDelegator

public MessageDelegator getDelegator()

returns the delegator that uses the RemoteDatabaseChangeHandler, which has been started in its own daemon thread at construction time

See Also:

getDelegatorThread()

addListener

public void addListener(DatabaseChangeListener l)

convenience method; delegates to the monitor

removeListener

public boolean removeListener(DatabaseChangeListener l)

convenience method; delegates to the monitor

close

public void close()

stops/closes both, notifier and handler; removes all listeners and sets all member variables to null

Specified by:

close in interface Closeable

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable