Package com.vaadin.base.devserver.devloop

Class DevLoopHotswapper

java.lang.Object

com.vaadin.base.devserver.devloop.DevLoopHotswapper

All Implemented Interfaces:

VaadinHotswapper

@Priority(10000)
public class DevLoopHotswapper
extends Object
implements VaadinHotswapper

An observer on Flow's own VaadinHotswapper SPI, so the dev loop can report what Flow did with a redefine rather than guess.

The daemon needs neither a completion signal nor a classification of its own: Flow already computes both, and onHotswapComplete is the authoritative "the runtime leg is done" event that a transaction gates on.

The Priority is deliberately large so this runs after Flow's own hotswappers (they sort ascending), meaning anything they decided has already been decided by the time this sees the event.

Flow does not expose the refresh strategy it computed - the public getUIUpdateStrategy only reports a strategy a hotswapper explicitly requested - so the strategy is logged for diagnosis but never used as the apply classification. The daemon reports what it did itself instead.

For internal use only. May be renamed or removed in a future release.

Since:

25.3

Constructor Summary

Constructors

Constructor	Description
DevLoopHotswapper()	Creates the hotswapper.

Method Summary

Modifier and Type	Method	Description
static DevLoopHotswapper	getActive()	The instance receiving hotswap events, or null before Flow's hotswapper has initialized.
boolean	isCompleted()	Whether Flow reported the hotswap complete since the last reset().
boolean	isPageReloadRequired()	Whether Flow decided a page reload is required for the changes seen since the last reset().
void	onClassesChange(HotswapClassEvent event)	Called by Vaadin hotswap entry point when one or more application classes have been updated.
void	onClassesChange(HotswapClassSessionEvent event)	Called by Vaadin hotswap entry point when one or more application classes have been updated.
void	onHotswapComplete(HotswapCompleteEvent event)	Called by Vaadin hotswap entry point after all hotswap related operations have been completed.
void	onInit(VaadinService vaadinService)	Called during the initialization of the Vaadin Hotswapper.
void	reset()	Clears recorded state before the next transaction.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.vaadin.base.devserver.hotswap.VaadinHotswapper

onClassLoadEvent, onClassLoadEvent, onResourcesChange

Constructor Details

DevLoopHotswapper

public DevLoopHotswapper()

Creates the hotswapper. It is found through the service loader.

Method Details

getActive

public static DevLoopHotswapper getActive()

The instance receiving hotswap events, or null before Flow's hotswapper has initialized.

Returns:

the active instance, or null

onInit

public void onInit(VaadinService vaadinService)

Description copied from interface: VaadinHotswapper

Called during the initialization of the Vaadin Hotswapper. This method provides an entry point for executing logic that needs to occur when the associated VaadinService is initialized and before any hotswap events are triggered.

Specified by:

onInit in interface VaadinHotswapper

Parameters:

vaadinService - the active VaadinService instance being initialized

onClassesChange

public void onClassesChange(HotswapClassEvent event)

Description copied from interface: VaadinHotswapper

Called by Vaadin hotswap entry point when one or more application classes have been updated.

This method is meant to perform application-wide updates. Operation targeting Vaadin session should be implemented in VaadinHotswapper.onClassesChange(HotswapClassSessionEvent) method.

Currently, the default implementation delegates to the deprecated VaadinHotswapper.onClassLoadEvent(VaadinService, Set, boolean) method for backward compatibility.

Specified by:

onClassesChange in interface VaadinHotswapper

Parameters:

event - the event instance carrying the information about the changed classes.

See Also:

• VaadinHotswapper.onClassesChange(HotswapClassSessionEvent)

onClassesChange

public void onClassesChange(HotswapClassSessionEvent event)

Description copied from interface: VaadinHotswapper

Called by Vaadin hotswap entry point when one or more application classes have been updated.

This method is meant to perform updates at VaadinSession level. Operation targeting the entire application should be implemented in VaadinHotswapper.onClassesChange(HotswapClassEvent) method.

Currently, the default implementation delegates to the deprecated VaadinHotswapper.onClassLoadEvent(VaadinSession, Set, boolean) method for backward compatibility.

Specified by:

onClassesChange in interface VaadinHotswapper

Parameters:

event - the event instance carrying the information about the changed classes.

See Also:

• VaadinHotswapper.onClassesChange(HotswapClassEvent)

onHotswapComplete

public void onHotswapComplete(HotswapCompleteEvent event)

Description copied from interface: VaadinHotswapper

Called by Vaadin hotswap entry point after all hotswap related operations have been completed.

Specified by:

onHotswapComplete in interface VaadinHotswapper

Parameters:

event - an event containing information about the hotswap operation.

reset

public void reset()

Clears recorded state before the next transaction.

isCompleted

public boolean isCompleted()

Whether Flow reported the hotswap complete since the last reset().

Returns:

true if onHotswapComplete was called

isPageReloadRequired

public boolean isPageReloadRequired()

Whether Flow decided a page reload is required for the changes seen since the last reset().

Returns:

true if a page reload is required