SK.gnome.dwarf.tcpip
Class Listener

java.lang.Object
  SK.gnome.dwarf.GenericService
      SK.gnome.dwarf.thread.ThreadService
          SK.gnome.dwarf.tcpip.Listener

All Implemented Interfaces:

java.lang.Runnable, Service

Direct Known Subclasses:

TCPListener, UDPListener

public abstract class Listener

extends ThreadService

Abstract service for receiving client requests.

This service just defines a set of common methods for a network listener. Subclasses must further add the required network listening functionality.

The setAddress(InetAddress) and setPort(int) methods can be used to setup an internet address and port on which the listener will receive the client requests. The setAllowedHosts(InetHostSet) and setDeniedHosts(InetHostSet) may be used to specify which clients will be accepted or rejected by the listener.

The protected method acceptHost(InetAddress) tests the given address against the internal sets of allowed and denied hosts, and returns true if a request from the given address may be accepted by the listener and forwarded to the server for further processing. This method may be overriden to implement a custom behaviour.

Field Summary

protected java.net.InetAddress	address The internet address to listen on.
protected InetHostSet	allowedHosts The set of allowed host ranges.
protected InetHostSet	deniedHosts The set of denied host ranges.
protected int	port The network port to listen on.

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

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

Method Summary

protected boolean	acceptHost(java.net.InetAddress address) Decides whether to accept a request from the given address.
void	setAddress(java.net.InetAddress address) Sets the internet address to listen on.
void	setAllowedHosts(InetHostSet hosts) Sets the allowed host ranges.
void	setDeniedHosts(InetHostSet hosts) Sets the denied host ranges.
void	setPort(int port) Sets the port to listen on.

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

enableThread, finish, loop, run, setDaemon, shutdown, start, stop

Methods inherited from class SK.gnome.dwarf.GenericService

getAuthenticator, getAuthFacility, getFullName, getInitParameter, getInitParameterNames, getLogFacility, getLogger, getName, getParameters, getPrincipal, getShutdownTimeout, getState, init, 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

Field Detail

address

protected java.net.InetAddress address

The internet address to listen on.

port

protected int port

The network port to listen on.

allowedHosts

protected InetHostSet allowedHosts

The set of allowed host ranges.

See Also:

setAllowedHosts(InetHostSet)

deniedHosts

protected InetHostSet deniedHosts

The set of denied host ranges.

See Also:

setDeniedHosts(InetHostSet)

Constructor Detail

Listener

public Listener(java.lang.String name)

Creates a new Listener.

Method Detail

setAddress

public void setAddress(java.net.InetAddress address)

Sets the internet address to listen on.

Parameters:

address - the internet address

See Also:

address

setPort

public void setPort(int port)

Sets the port to listen on.

Parameters:

port - the port

See Also:

port

setAllowedHosts

public void setAllowedHosts(InetHostSet hosts)

Sets the allowed host ranges.

Parameters:

hosts - the host range list

See Also:

acceptHost(InetAddress), InetHostSet

setDeniedHosts

public void setDeniedHosts(InetHostSet hosts)

Sets the denied host ranges.

Parameters:

hosts - the host range list

See Also:

acceptHost(InetAddress), InetHostSet

acceptHost

protected boolean acceptHost(java.net.InetAddress address)

Decides whether to accept a request from the given address.

The decision is based on the sets of allowed/denied host ranges. The current alghoritm works as follows: if the allowedHosts is not null and does not imply the given address, the method return false, otherwise the deniedHosts is consulted. If it is not null and implies the given address, false is returned, otherwise true is returned.

This method can be overriden to customize the listener's way of accepting client request.