SK.gnome.dwarf.thread
Class Handler

java.lang.Object
  SK.gnome.dwarf.GenericService
      SK.gnome.dwarf.thread.ThreadService
          SK.gnome.dwarf.thread.Handler

All Implemented Interfaces:

java.lang.Runnable, Service, Stoppable

Direct Known Subclasses:

NioTCPHandler, TCPHandler, UDPHandler

public abstract class Handler

extends ThreadService

implements Stoppable

Abstract service for handling the client requests.

This class processes the client requests. It works in cooperation with the MultiThreadServer.

In order to develop a real handler the abstract handle(Object) method must be overriden.

Field Summary

Fields inherited from class SK.gnome.dwarf.thread.ThreadService

daemon, thread

Fields inherited from class SK.gnome.dwarf.GenericService

initParameters, parent

Fields inherited from interface SK.gnome.dwarf.Service

INITIALIZED, LOG_DEBUG, LOG_ERROR, LOG_FATAL, LOG_INFO, LOG_TRACE, LOG_WARN, LOG_XFER, SHUTDOWN, STARTED, STOPPED

Constructor Summary

Handler(java.lang.String name)
Creates a new Handler.

Method Summary

protected boolean	enableThread() Enables or disables the service thread.
protected abstract void	handle(java.lang.Object obj) Handles the client request.
void	init(Server parent) Initializes the service.
protected void	loop() Performs the handling operation.
void	start() Starts the service.

Methods inherited from class SK.gnome.dwarf.thread.ThreadService

finish, run, setDaemon, shutdown, stop

Methods inherited from class SK.gnome.dwarf.GenericService

getAuthenticator, getAuthFacility, getFullName, getInitParameter, getInitParameterNames, getLogFacility, getLogger, getName, getParameters, getPrincipal, getShutdownTimeout, getState, log, log, login, logout, setAuthFacility, setInitParameters, setLogFacility, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

Handler

public Handler(java.lang.String name)

Creates a new Handler.

Method Detail

init

public void init(Server parent)
          throws ServiceException

Initializes the service.

It requires that the parent server is an instance of MultiThreadServer class.

Specified by:

init in interface Service

Overrides:

init in class GenericService

Throws:

ServiceException

start

public void start()
           throws ServiceException

Description copied from class: ThreadService

Starts the service.

If the ThreadService.enableThread() method returns true, it creates and starts a new thread. The thread's name corresponds to the service name and the thread's Runnable target is the service itself since it implements the Runnable interface. The reference to the thread object is stored in the ThreadService.thread field.

It throws a IllegalStateException if the ThreadService.thread field is not null and its isAlive() method returns true.

Specified by:

start in interface Service

Overrides:

start in class ThreadService

Throws:

ServiceException

enableThread

protected boolean enableThread()

Enables or disables the service thread.

This method always returns true, so the new thread is always started.

Overrides:

enableThread in class ThreadService

Returns:

true if the thread is enabled

loop

protected void loop()

Performs the handling operation.

First calls the parent server's MultiThreadServer.dequeue(int) method and then passes the obtained request object to the handle(Object) method for further processing. After that handler returns the obtained request to the server via its MultiThreadServer.finish(Object) method.

Overrides:

loop in class ThreadService

handle

protected abstract void handle(java.lang.Object obj)

Handles the client request.

The abstract method for processing the client requests. It must be overriden in order to implement a real handler. The client request is generally represented by the obj argument. Since it is an instance of the basic java.lang.Object class, it can represent an arbitrary client request.