org.soulwing.snmp

Interface SnmpListener

public interface SnmpListener

A component that listens for SNMP notifications (traps, informs) and makes them available to registered handlers.

Conceptually, a listener represents a provider component that listens for incoming SNMP notifications at the transport layer of the network. Typically, an implementation binds a socket to an IP address and port and receives all incoming SNMP notifications received on that socket.

A listener maintains an ordered collection of handlers, based on a priority specified when each handler is registered. When an SNMP notification is received, registered handlers are invoked in priority order. When a handler indicates that it handled the event (via the return value of SnmpNotificationHandler.handleNotification(SnmpNotificationEvent)), handlers of lower priority are not invoked.

The listener can be used to implement a strategy for handling different types of notifications, where a given handler supports one notification type (or perhaps a set of closely related types). For each received notification, the listener will ask each registered handler (in priority order) to handle the notification, stopping with the first handler that claims to have done so.

Author:

Carl Harris

Method Summary

Methods

Modifier and Type	Method and Description
void	addHandler(SnmpNotificationHandler handler) Adds a notification handler.
void	addHandler(SnmpNotificationHandler handler, int priority) Adds a notification handler.
void	close() Closes this listener.
void	removeHandler(SnmpNotificationHandler handler) Removes a notification handler.

Method Detail

addHandler

void addHandler(SnmpNotificationHandler handler)

Adds a notification handler.

The handler will be added to the collection such that it is notified after all previously registered handlers.

This method has no effect if a handler identical to handler is already registered.

Parameters:

handler - the handler to add

addHandler

void addHandler(SnmpNotificationHandler handler,
              int priority)

Adds a notification handler.

The handler will be added to the collection, such that it is notified after all previously registered handlers whose priority is less than or equal to the specified priority.

This method has no effect if a handler identical to handler is already registered.

Parameters:

handler - the handler to add

priority - priority for the handler

removeHandler

void removeHandler(SnmpNotificationHandler handler)

Removes a notification handler.

This method has no effect if handler is not registered

Parameters:

handler - the handler to remove

close

void close()

Closes this listener.

After the listener has been closed, no further notifications will be distributed to handlers.