org.realityforge.gwt.webpoller.client

Class WebPoller

java.lang.Object

org.realityforge.gwt.webpoller.client.WebPoller

Direct Known Subclasses:

TimerBasedWebPoller

public abstract class WebPoller
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	WebPoller.Factory

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	WebPoller(EventBus eventBus)

Method Summary

Methods

Modifier and Type	Method and Description
HandlerRegistration	addErrorHandler(ErrorEvent.Handler handler)
HandlerRegistration	addMessageHandler(MessageEvent.Handler handler)
HandlerRegistration	addStartHandler(StartEvent.Handler handler)
HandlerRegistration	addStopHandler(StopEvent.Handler handler)
static boolean	deregister(WebPoller.Factory factory)
protected void	doPoll() Sub-classes should override to perform actual polling.
protected void	doStart() Sub-classes should override this method to provide functionality.
protected void	doStop() Sub-classes should override this method to provide functionality.
int	getErrorCountThreshold()
protected EventBus	getEventBus()
int	getPollDuration()
protected RequestContext	getRequestContext()
RequestFactory	getRequestFactory()
boolean	inError()
boolean	isActive()
protected boolean	isInPoll()
boolean	isLongPoll()
boolean	isPaused()
static WebPoller	newWebPoller()
protected void	onEmptyPollResult() Invoked after a successful poll returning no data.
protected void	onError(java.lang.Throwable exception) Fire an Error event.
protected void	onMessage(java.util.Map<java.lang.String,java.lang.String> context, java.lang.String data) Fire a Message event.
protected void	onStart() Fire a Start event.
protected void	onStop() Fire a Stop event.
void	pause() Pause the active poller.
protected void	poll() Orchestrate the polling.
protected void	pollReturned() This should be invoked when the poll has completed.
static void	register(WebPoller.Factory factory)
void	resume() Resume an already paused poller.
void	setErrorCountThreshold(int errorCountThreshold) Set the number of errors before poller is stopped.
void	setLongPoll(boolean longPoll)
void	setPollDuration(int pollDuration)
void	setRequestFactory(RequestFactory requestFactory)
void	start() Start polling.
void	stop() Stop polling.

Methods inherited from class java.lang.Object

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

Constructor Detail

WebPoller

protected WebPoller(@Nonnull
         EventBus eventBus)

Method Detail

newWebPoller

public static WebPoller newWebPoller()

register

public static void register(@Nonnull
            WebPoller.Factory factory)

deregister

public static boolean deregister(@Nonnull
                 WebPoller.Factory factory)

isActive

public boolean isActive()

Returns:

true if the poller is active.

inError

public boolean inError()

Returns:

false if stopped, otherwise true if the the last poll resulted in error.

start

public final void start()
                 throws java.lang.IllegalStateException

Start polling.

Throws:

java.lang.IllegalStateException - if the poller is already active.

stop

public final void stop()
                throws java.lang.IllegalStateException

Stop polling.

Throws:

java.lang.IllegalStateException - if the poller is not active.

setRequestFactory

public void setRequestFactory(@Nullable
                     RequestFactory requestFactory)

getRequestFactory

public final RequestFactory getRequestFactory()

getErrorCountThreshold

public final int getErrorCountThreshold()

Returns:

the number of errors before poller is stopped.

setErrorCountThreshold

public void setErrorCountThreshold(int errorCountThreshold)

Set the number of errors before poller is stopped.

getPollDuration

public final int getPollDuration()

setPollDuration

public final void setPollDuration(int pollDuration)

isLongPoll

public final boolean isLongPoll()

setLongPoll

public void setLongPoll(boolean longPoll)
                 throws java.lang.IllegalStateException

Throws:

java.lang.IllegalStateException

pause

public void pause()

Pause the active poller. The poller will cease actually polling until resume is called.

Throws:

java.lang.IllegalStateException - if poller is not active or poller is already paused

resume

public void resume()

Resume an already paused poller. The poller will resume polling.

Throws:

java.lang.IllegalStateException - if poller is not active or poller is not paused.

isPaused

public boolean isPaused()

Returns:

true if poller is paused.

getEventBus

protected final EventBus getEventBus()

doStop

protected void doStop()

Sub-classes should override this method to provide functionality.

doStart

protected void doStart()

Sub-classes should override this method to provide functionality.

onEmptyPollResult

protected final void onEmptyPollResult()

Invoked after a successful poll returning no data.

addStartHandler

@Nonnull
public final HandlerRegistration addStartHandler(@Nonnull
                                          StartEvent.Handler handler)

addStopHandler

@Nonnull
public final HandlerRegistration addStopHandler(@Nonnull
                                         StopEvent.Handler handler)

addMessageHandler

@Nonnull
public final HandlerRegistration addMessageHandler(@Nonnull
                                            MessageEvent.Handler handler)

addErrorHandler

@Nonnull
public final HandlerRegistration addErrorHandler(@Nonnull
                                          ErrorEvent.Handler handler)

onStart

protected final void onStart()

Fire a Start event.

onStop

protected final void onStop()

Fire a Stop event.

onMessage

protected final void onMessage(@Nonnull
             java.util.Map<java.lang.String,java.lang.String> context,
             @Nonnull
             java.lang.String data)

Fire a Message event.

onError

protected final void onError(@Nonnull
           java.lang.Throwable exception)

Fire an Error event. If the number of successive errors reaches a threshold then shut-down the poller.

isInPoll

protected final boolean isInPoll()

Returns:

true if a poll request is outstanding.

pollReturned

protected void pollReturned()

This should be invoked when the poll has completed. It may be overriden by sub-classes to perform other cleanup.

poll

protected final void poll()

Orchestrate the polling.

getRequestContext

protected final RequestContext getRequestContext()

doPoll

protected void doPoll()

Sub-classes should override to perform actual polling.