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Target

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pentaho.type.action.impl. Target

The Target class is a mixin class that builds upon EventSource to implement the ITarget interface.

It provides a generic action Execution implementation which delegates to the event observers of each of the execution phases.

The event observers have the following signature:

function(event, action) {

  // assert event instanceof pentaho.type.action.Execution;

  // assert action === event.action;
  // assert action instanceof pentaho.type.action.Base;

  // assert this === event.target;
  // assert this instanceof pentaho.type.action.ITarget;
}

The do phase event observer can return a Promise.

AMD Module 

require(["pentaho/type/action/impl/Target"], function(Target) { /* code goes here */ });

Extends

Implements

Constructor

Name Description
new Target()
Abstract

This class was not designed to be constructed directly. It was designed to be used as a mixin.

Classes

Name Summary
GenericActionExecution

The GenericActionExecution class is an inner class of Target that assumes that that the execution target is a Target.

Methods

Name Description
_createActionExecution(action) : pentaho.type.action.Execution
Protected

Creates an action execution for a given action.
_createGenericActionExecution(action) : pentaho.type.action.Execution
Protected

Creates a generic action execution for a given action.
_emit(event) : pentaho.lang.Event
Protected

Emits an unstructured event and returns it, unless it was canceled.
_emitActionPhaseDoEvent(actionExecution) : Promise
Protected

Emits the do phase event of an action execution.
_emitActionPhaseFinallyEvent(actionExecution)
Protected

Emits the finally phase event of an action execution.
_emitActionPhaseInitEvent(actionExecution)
Protected

Emits the init phase event of an action execution.
_emitActionPhaseWillEvent(actionExecution)
Protected

Emits the will phase event of an action execution.
_emitGeneric(source, eventArgs, type, phase, keyArgs) : boolean
Protected

Emits an event given an arbitrary payload object, its type and phase. Returns the event payload object, unless the event is canceled.
_emitGenericAllAsync(source, eventArgs, type, phase, keyArgs) : Promise.<object>
Protected

Emits an event asynchronously, given an arbitrary payload object, its type and phase, and succeeding if every listener succeeds.
_emitSafe(event) : pentaho.lang.Event
Protected

Variation of the _emit method in which errors thrown by event listeners are caught and logged.
_hasListeners(type, phase) : boolean
Protected

Determines if there are any registrations for a given event type and, optionally, phase.
act(action) : pentaho.type.action.Execution

Executes or starts execution of a given action in this target and returns the corresponding action execution instance.
off(typeOrHandle, observer)

Removes one registration given its handle, or all registrations of a given event type (or types) and observer (or listener function).
on(type, observer, keyArgs) : pentaho.lang.IEventRegistrationHandle

Registers an observer (or listener function) for an event(s) of a given type(s).

Constructor Details

new Target()
Abstract

This class was not designed to be constructed directly. It was designed to be used as a mixin.

Source: javascript/web/pentaho/type/action/impl/Target.js, line 89

Methods Details

_createActionExecution(action) : pentaho.type.action.Execution
Protected

Creates an action execution for a given action.

The default implementation delegates to [_createGenericActionExecution]{pentaho.type.action.impl.Target#_createGenericActionExecution}.

Source: javascript/web/pentaho/type/action/impl/Target.js, line 156

Parameters:
Name Default Value Summary
action : pentaho.type.action.Base

The action which will be executed.
Returns:
Name Description
pentaho.type.action.Execution

The action execution.

See also: pentaho.type.action.ITarget#act

_createGenericActionExecution(action) : pentaho.type.action.Execution
Protected

Creates a generic action execution for a given action.

The implementation returns an instance of Target.GenericActionExecution.

Source: javascript/web/pentaho/type/action/impl/Target.js, line 172

Parameters:
Name Default Value Summary
action : pentaho.type.action.Base

The action which will be executed.
Returns:
Name Description
pentaho.type.action.Execution

The action execution.
_emit(event) : pentaho.lang.Event
Protected

Emits an unstructured event and returns it, unless it was canceled.

When this method is called, the listeners of existing registrations are notified synchronously, by priority order and then registration order, until either the event is canceled or all of the listeners have been notified.

It is safe to register or unregister to/from an event type while it is being emitted. However, changes are only taken into account in subsequent emissions.

If a listener function throws an error, the event processing is interrupted. No more registrations are processed and the error is passed to the caller.

Source: javascript/web/pentaho/lang/EventSource.js, line 269

Inherited From: pentaho.lang.EventSource#_emit

Parameters:
Name Default Value Summary
event : pentaho.lang.Event

The event object.
Returns:
Name Description
pentaho.lang.Event | null

The given event object or null, when canceled.

See also: pentaho.lang.EventSource#_emitSafe , pentaho.lang.EventSource#_emitGeneric

_emitActionPhaseDoEvent(actionExecution) : Promise
Protected

Emits the do phase event of an action execution.

The default implementation delegates to _emitGenericAllAsync, when the action is asynchronous. Delegates to _emitGeneric, otherwise.

Source: javascript/web/pentaho/type/action/impl/Target.js, line 230

Parameters:
Name Default Value Summary
actionExecution : pentaho.type.action.Execution

The action execution.
Returns:
Name Description
Promise | null

A promise to the completion of the asynchronous do listener, of an asynchronous action, or null.
_emitActionPhaseFinallyEvent(actionExecution)
Protected

Emits the finally phase event of an action execution.

The default implementation delegates to _emitGeneric.

Source: javascript/web/pentaho/type/action/impl/Target.js, line 254

Parameters:
Name Default Value Summary
actionExecution : pentaho.type.action.Execution

The action execution.
_emitActionPhaseInitEvent(actionExecution)
Protected

Emits the init phase event of an action execution.

The default implementation delegates to _emitGeneric.

Source: javascript/web/pentaho/type/action/impl/Target.js, line 188

Parameters:
Name Default Value Summary
actionExecution : pentaho.type.action.Execution

The action execution.
_emitActionPhaseWillEvent(actionExecution)
Protected

Emits the will phase event of an action execution.

The default implementation delegates to _emitGeneric.

Source: javascript/web/pentaho/type/action/impl/Target.js, line 206

Parameters:
Name Default Value Summary
actionExecution : pentaho.type.action.Execution

The action execution.
_emitGeneric(source, eventArgs, type, phase, keyArgs) : boolean
Protected

Emits an event given an arbitrary payload object, its type and phase. Returns the event payload object, unless the event is canceled.

Source: javascript/web/pentaho/lang/EventSource.js, line 325

Inherited From: pentaho.lang.EventSource#_emitGeneric

Parameters:
Name Default Value Summary
source : object

The this value of listener functions.
eventArgs : Array

The arguments of listener functions.
type : nonEmptyString

The type of the event.
phase : nonEmptyString
Optional

The phase of the event. For unstructured events don't specify this argument (or specify a Nully value).
keyArgs : Object
Optional

The keyword arguments' object.

Parameters:
Name Default Value Summary
isCanceled : function
Optional

A predicate that indicates if the given event args are in a canceled state. Its this value is the value of source.
errorHandler : function
Optional

When specified with a null value, no error handling is performed and errors thrown by listeners are thrown back to this method's caller. When unspecified or specified as undefined, defaults to a function that simply logs the listener errors, and lets execution continue to the following listeners. The function arguments are: the error, the eventArgs, the event type and the event phase. Its this value is the value of source.
interceptor : function
Optional
 null

A function which is called for each event listener function, with the arguments listener, source, eventArgs and the index of the listener.
Returns:
Name Description
boolean

false when the event is canceled; true, otherwise.
_emitGenericAllAsync(source, eventArgs, type, phase, keyArgs) : Promise.<object>
Protected

Emits an event asynchronously, given an arbitrary payload object, its type and phase, and succeeding if every listener succeeds.

Listeners are called in parallel.

Returns a promise that is fulfilled or rejected with the event payload object. If any listener throws or rejects, the returned promise is rejected as well.

Source: javascript/web/pentaho/lang/EventSource.js, line 454

Inherited From: pentaho.lang.EventSource#_emitGenericAllAsync

Parameters:
Name Default Value Summary
source : object

The this value of listener functions.
eventArgs : Array

The arguments of listener functions.
type : nonEmptyString

The type of the event.
phase : nonEmptyString
Optional

The phase of the event. For unstructured events don't specify this argument (or specify a Nully value).
keyArgs : Object
Optional

The keyword arguments' object.

Parameters:
Name Default Value Summary
isCanceled : function
Optional

A predicate that indicates if the given event args are in a canceled state. Its this value is the value of source.
getCancellationReason : function
Optional

A function that given the event args returns its a cancellation reason, usually an Error. Its this value is the value of source.
errorHandler : function
Optional

When specified with a null value, no error handling is performed. Errors thrown by, or promises rejected by, any listeners cause the whole event to be rejected.

When unspecified or specified as undefined, defaults to a function that simply logs any listener errors, yet always succeeding.

The function arguments are: the error, the event, the event type and the event phase.
Returns:
Name Description
Promise.<object>

A promise. When fulfilled, it is with the value undefined. When rejected due to a thrown error, the rejection reason is that error. When explicitly rejected by the error handler, the given rejection reason is preserved. When rejected due to a cancellation, the rejection reason is the cancellation reason, if any.
_emitSafe(event) : pentaho.lang.Event
Protected

Variation of the _emit method in which errors thrown by event listeners are caught and logged.

If an event listener throws an error, the following event listeners are still processed.

Source: javascript/web/pentaho/lang/EventSource.js, line 291

Inherited From: pentaho.lang.EventSource#_emitSafe

Parameters:
Name Default Value Summary
event : pentaho.lang.Event

The event object.
Returns:
Name Description
pentaho.lang.Event | null

The given event object or null, when canceled.

See also: pentaho.lang.EventSource#_emit , pentaho.lang.EventSource#_emitGeneric

_hasListeners(type, phase) : boolean
Protected

Determines if there are any registrations for a given event type and, optionally, phase.

This method can be used to avoid creating expensive event objects for an event type and, optionally, phase, that don't have registrations.

Source: javascript/web/pentaho/lang/EventSource.js, line 218

Inherited From: pentaho.lang.EventSource#_hasListeners

Parameters:
Name Default Value Summary
type : nonEmptyString

The type of the event.
phase : nonEmptyString
Optional

The phase of a structured event. For unstructured events don't specify this argument. For structured events, if this argument is not specified, the result will be true if there are any listeners, for any of the phases.
Returns:
Name Description
boolean

true if the event has any listeners for the given event type and phase; false, otherwise.

Examples

if(this._hasListeners("click")) {

 var event = new Event("click", this, true);

 if(this._emit(event)) {
 // ...
 }
}
if(this._hasListeners("select")) {

 var event = new Event("select");

 if(this._emitGeneric(this, [event], "select", "will")) {

 // Select ...

 this._emitGeneric(this, [event], "select", "finally");
 }
}
Implements:
act(action) : pentaho.type.action.Execution

Executes or starts execution of a given action in this target and returns the corresponding action execution instance.

This method can be given synchronous or asynchronous actions. To wait for the result of an asynchronous action, obtain the promise property of the returned action execution instance.

Source: doc-js/pentaho/type/action/ITarget.jsdoc, line 37

Parameters:
Name Default Value Summary
action : pentaho.type.action.Base | pentaho.type.action.spec.IBase

The action or action specification to execute.
Returns:
Name Description
pentaho.type.action.Execution

The resulting action execution.
Implements:
off(typeOrHandle, observer)

Removes one registration given its handle, or all registrations of a given event type (or types) and observer (or listener function).

To remove an event registration, it is sufficient to call the dispose method of the registration handle returned by on, upon registration. Alternatively, as a convenience syntax, the registration handle can be passed as the single argument to this method.

It is safe to unregister from an event type while it is being emitted. However, any registrations removed during the current emission will still execute.

Specifying an event registration handle that has already been disposed of has no effect. Specifying an event type and observer (or listener function) that have no registrations has no effect.

Source: doc-js/pentaho/lang/IEventSource.jsdoc, line 131

Inherited From: pentaho.lang.EventSource#off

Parameters:
Name Default Value Summary
typeOrHandle : nonEmptyString | Array.<nonEmptyString> | pentaho.lang.IEventRegistrationHandle

The type or types of events, or an event registration handle to dispose of. When a string, it can be a comma-separated list of event types.
observer : pentaho.lang.IEventObserver | pentaho.lang.EventListener | pentaho.lang.EventListenerAsync

The event observer (or listener function). Required when typeOrHandle is not an event registration handle; ignored, otherwise.

See also: pentaho.lang.IEventSource#on

Implements:
on(type, observer, keyArgs) : pentaho.lang.IEventRegistrationHandle

Registers an observer (or listener function) for an event(s) of a given type(s).

Optionally, a listening priority may be specified to adjust the order by which an observer is notified, relative to other listeners.

Note that if an observer is registered more than once to the same event type, a new registration is created each time and its listeners will be called once per registration.

It is safe to register for an event type while it is being emitted. However, new registrations are only taken into account in subsequent emissions.

When type represents multiple event types, the returned event registration handle is a composite registration for all of the event types.

This method is compatible with the dojo/on API.

Source: doc-js/pentaho/lang/IEventSource.jsdoc, line 90

Inherited From: pentaho.lang.EventSource#on

Parameters:
Name Default Value Summary
type : nonEmptyString | Array.<nonEmptyString>

The type or types of events. When a string, it can be a comma-separated list of event types.
observer : pentaho.lang.IEventObserver | pentaho.lang.EventListener | pentaho.lang.EventListenerAsync

The event observer (or listener function).
keyArgs : object
Optional

Keyword arguments.

Parameters:
Name Default Value Summary
priority : number
Optional
 0

The listening priority. Higher priority observers are notified of an event before any lower priority observers. The priority can be set to -Infinity or Infinity. In case two observers are assigned the same priority, the registration order determines which is notified first.
Returns:
Name Description
pentaho.lang.IEventRegistrationHandle

An event registration handle that can be used for later removal.

See also: pentaho.lang.IEventSource#off

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