talx.controller.extended
Class GossipInterceptor

java.lang.Object
  talx.controller.extended.GossipInterceptor

All Implemented Interfaces:

Interceptor, TALFeature

public class GossipInterceptor

extends java.lang.Object

implements Interceptor

Constructor Summary

GossipInterceptor()

Method Summary

boolean	claim(java.awt.event.ActionEvent ev, Controller c) Determines whether this feature is responsible for the action.
void	controllerChange(ControllerChangeEvent ev)
void	controllerChangeFinished(ChangeFinishedEvent ev)
void	initialize(Controller c) Allows the interceptor to change the gui state.
void	release() Releases all system resources held by this object.

Methods inherited from class java.lang.Object

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

Constructor Detail

GossipInterceptor

public GossipInterceptor()

Method Detail

claim

public boolean claim(java.awt.event.ActionEvent ev,
                     Controller c)
              throws ActionVetoException

Description copied from interface: Interceptor

Determines whether this feature is responsible for the action. In response to this method, the feature can:

• Claim the action and update the volatile state
• Not claim the action and not update the volatile state
• Veto the Action and not update the volatile state

Each feature can manage its own state in any way, including updating its state in response to unclaimed or vetoed actions. However, a feature may not update the volatile state without claiming the action. This is because the controller will not fire a changeFinishedEvent if the action is vetoed. Since, by not claiming the state, a feature leaves open the possibilty that another feature will veto it, it is only safe to update the state on actions that it claims. Once an action is claimed, the controller fires a changeFinishedEvent and stops propagating the action through the chain of responsibility.

Interceptors that wish to make some minor change to the gui state but not stop other effects from an action must make their change, refire the action via the controller's doAction() method, and then claim the action. Obviously, such interceptors must remember the action event to prevent them from reacting to it the next time.

Unlike ActionHandlers, which are stateless, Interceptors must manage their own state.

Specified by:

claim in interface Interceptor

Returns:

true to claim the action, false otherwise.

Throws:

ActionVetoException - to veto the action.

initialize

public void initialize(Controller c)

Description copied from interface: Interceptor

Allows the interceptor to change the gui state. This method is called in the controller init method just after the controller restores the state but before it fires the first controller change event.

Specified by:

initialize in interface Interceptor

release

public void release()

Description copied from interface: TALFeature

Releases all system resources held by this object. The general contract of pluggable features is that once their release method is called, they should be elligible for garbage collection. The exceptions to this are references to this object held in the ActionDispatcher and in the Transport model. Both of those objects are cleared by the system. However, in all other cases, if this object subscribed to a listener interface, it must unsubscribe in this method. This method should block until all object clean-up has been accomplished. This includes closing all open files, etc. Once the object has returned from the release method, the system may go down without further warning.

Specified by:

release in interface TALFeature

controllerChange

public void controllerChange(ControllerChangeEvent ev)

controllerChangeFinished

public void controllerChangeFinished(ChangeFinishedEvent ev)