one.world.core
Class Event

java.lang.Object
  |
  +--one.world.core.Tuple
        |
        +--one.world.core.Event

All Implemented Interfaces:

Cloneable, Serializable

Direct Known Subclasses:

AnnounceEvent, BindingRequest, BindingResponse, ChunkRequest, ChunkResponse, DynamicTuple, ElectionEvent, EmptyEvent, ExceptionalEvent, HttpEvent, IdEvent, IdsEvent, IteratorRequest, IteratorResponse, JoinRequest, JoinResponse, ListenResponse, LogEvent, Message, PingPongEvent, QueryResponse, RemoteEvent, ResolutionRequest, ResolutionResponse, TupleEvent, TypedEvent

public abstract class Event

extends Tuple

The superclass of all events. Event objects are tuples that encapsulate all necessary state when notifying an EventHandler of the occurence of some logical event.

Version:

$Revision: 1.14 $

See Also:

Serialized Form

Field Summary

Object	closure The closure for this event.
EventHandler	source The source for this event.

Fields inherited from class one.world.core.Tuple

CLOSURE, id, ID, META_DATA, metaData, SOURCE

Constructor Summary

Event()
Create a new, empty event.

Event(EventHandler source, Object closure)
Create a new event with the specified source and closure.

Event(Guid id, EventHandler source, Object closure)
Create a new event with the specified ID, source, and closure.

Method Summary

void	validate() Validate this event.

Methods inherited from class one.world.core.Tuple

clone, containsNonSymbolicHandler, equals, fields, get, getMetaData, getType, hasField, hashCode, hasMetaData, remove, set, setMetaData, toString, wrap

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

source

public EventHandler source

The source for this event. The source of an event indicates the resource that originally creates the event. Typically, this field points to an event handler that can be used for call-backs in request-response interactions. The source of an event must not be null.

closure

public Object closure

The closure for this event. The closure of an event is an opaque object that is simply passed through. Typically, a "client" in a request-response interaction uses the closure to distinguish between several response events processed by the same event handler.

Constructor Detail

Event

public Event()

Create a new, empty event.

Event

public Event(EventHandler source,
             Object closure)

Create a new event with the specified source and closure. This constructor creates a new event with the specified source and closure. The ID field is assigned a new GUID.

Parameters:

source - The source for the new event.

closure - The closure for the new event.

Event

public Event(Guid id,
             EventHandler source,
             Object closure)

Create a new event with the specified ID, source, and closure.

Parameters:

id - The ID for the new event.

source - The source for the new event.

closure - The closure for the new event.

Method Detail

validate

public void validate()
              throws TupleException

Validate this event. This method ensures that the source of an event is not null. It also validates the closure, if that object is validatable. Classes that override this method must first call the corresponding method in their superclass.

Overrides:

validate in class Tuple

Following copied from class: one.world.core.Tuple

Throws:

TupleException - Signals that the tuple is either malformed (i.e., does not conform to the tuple specification) or invalid (i.e., does not conform to the semantic constraints of its type).

See Also:

MalformedTupleException, InvalidTupleException, Type.validate(Class)