com.smartgwt.client.util

Class CancellationController

java.lang.Object

com.smartgwt.client.core.BaseClass

com.smartgwt.client.util.CancellationController

All Implemented Interfaces:

com.google.gwt.event.shared.HasHandlers

public class CancellationController
extends BaseClass

Provides a mechanism for canceling asynchronous operations.

Field Summary

Fields inherited from class com.smartgwt.client.core.BaseClass

config, configOnly, factoryCreated, factoryProperties, id, scClassName

Constructor Summary

Constructors

Constructor and Description
CancellationController()
CancellationController(com.google.gwt.core.client.JavaScriptObject jsObj)

Method Summary

Modifier and Type	Method and Description
java.lang.Boolean	cancel() Requests cancellation of all asynchronous operations that are polling canceled or observing this method.
java.lang.Boolean	cancel(java.lang.String reason) Requests cancellation of all asynchronous operations that are polling canceled or observing this method.
com.google.gwt.core.client.JavaScriptObject	create()
CancellationController	createSubController() Creates a new CancellationController which is canceled whenever this CancellationController is canceled.
java.lang.Boolean	getCanceled() Whether cancel() has been called.
java.lang.String	getCancellationReason() The reason, if any, passed to the first call to cancel().
com.google.gwt.core.client.JavaScriptObject	getJsObj()
com.google.gwt.core.client.JavaScriptObject	getOrCreateJsObj()
static CancellationController	getOrCreateRef(com.google.gwt.core.client.JavaScriptObject jsObj)
boolean	isCreated()
void	setJavaScriptObject(com.google.gwt.core.client.JavaScriptObject jsObj)

Methods inherited from class com.smartgwt.client.core.BaseClass

addDynamicProperty, addDynamicProperty, addDynamicProperty, addDynamicProperty, applyFactoryProperties, asSGWTComponent, clearDynamicProperty, createJsObj, destroy, doAddHandler, doInit, error, error, errorIfNotCreated, fireEvent, getAttribute, getAttributeAsBoolean, getAttributeAsDate, getAttributeAsDouble, getAttributeAsElement, getAttributeAsFloat, getAttributeAsInt, getAttributeAsJavaScriptObject, getAttributeAsMap, getAttributeAsString, getAttributeAsStringArray, getClassName, getConfig, getHandlerCount, getID, getRef, getRuleScope, getScClassName, getTestInstance, hasAutoAssignedID, hasDynamicProperty, internalSetID, internalSetID, isConfigOnly, isFactoryCreated, onBind, onInit, registerID, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setAttribute, setConfig, setConfigOnly, setFactoryCreated, setID, setProperty, setProperty, setProperty, setProperty, setRuleScope, setScClassName

Methods inherited from class java.lang.Object

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

Constructor Detail

CancellationController

public CancellationController()

CancellationController

public CancellationController(com.google.gwt.core.client.JavaScriptObject jsObj)

Method Detail

getOrCreateRef

public static CancellationController getOrCreateRef(com.google.gwt.core.client.JavaScriptObject jsObj)

setJavaScriptObject

public void setJavaScriptObject(com.google.gwt.core.client.JavaScriptObject jsObj)

Overrides:

setJavaScriptObject in class BaseClass

create

public com.google.gwt.core.client.JavaScriptObject create()

Specified by:

create in class BaseClass

isCreated

public boolean isCreated()

Overrides:

isCreated in class BaseClass

getJsObj

public com.google.gwt.core.client.JavaScriptObject getJsObj()

Overrides:

getJsObj in class BaseClass

getOrCreateJsObj

public com.google.gwt.core.client.JavaScriptObject getOrCreateJsObj()

Overrides:

getOrCreateJsObj in class BaseClass

getCanceled

public java.lang.Boolean getCanceled()
                              throws java.lang.IllegalStateException

Whether cancel() has been called.

Note : This method should be called only after the underlying component has been created.

Returns:

Current canceled value. Default value is false

Throws:

java.lang.IllegalStateException - if the underlying component has not yet been created.

getCancellationReason

public java.lang.String getCancellationReason()
                                       throws java.lang.IllegalStateException

The reason, if any, passed to the first call to cancel().

Note : This method should be called only after the underlying component has been created.

Returns:

Current cancellationReason value. Default value is null

Throws:

java.lang.IllegalStateException - if the underlying component has not yet been created.

See Also:

HTMLString

cancel

public java.lang.Boolean cancel()

Requests cancellation of all asynchronous operations that are polling canceled or observing this method. Also cancels any sub-CancellationControllers of this CancellationController that are not already canceled.

this.cancellationReason is set to the provided reason only on the first call to cancel().

For observers of this method, the recommended practice is to capture the returnVal and only perform the cancellation steps if the returnVal was true. This is because it could happen that cancel() is called a second time before the observers finish.

Returns:

true if this was the first call to cancel(); false otherwise.

cancel

public java.lang.Boolean cancel(java.lang.String reason)

Requests cancellation of all asynchronous operations that are polling canceled or observing this method. Also cancels any sub-CancellationControllers of this CancellationController that are not already canceled.

this.cancellationReason is set to the provided reason only on the first call to cancel().

For observers of this method, the recommended practice is to capture the returnVal and only perform the cancellation steps if the returnVal was true. This is because it could happen that cancel() is called a second time before the observers finish.

Parameters:

reason - A reason for cancellation. See HTMLString

Returns:

true if this was the first call to cancel(); false otherwise.

createSubController

public CancellationController createSubController()

Creates a new CancellationController which is canceled whenever this CancellationController is canceled.

Note that the sub-CancellationController may be independently canceled before this parent CancellationController is canceled.

Returns:

a new CancellationController that is canceled whenever this CancellationController is canceled.