Package com.vaadin.flow.component

Class ComponentEventBusUtil

java.lang.Object

com.vaadin.flow.component.ComponentEventBusUtil

public class ComponentEventBusUtil
extends Object

Static helpers and caching functionality for ComponentEventBus.

Since:

1.0

Author:

Vaadin Ltd

Method Summary

Modifier and Type	Method	Description
static <T extends ComponentEvent<?>> Constructor<T>	getEventConstructor(Class<T> eventType)	Gets the constructor to use for firing a component event, of the given type, based on a DOM event.
static LinkedHashMap<String,Class<?>>	getEventDataExpressions(Class<? extends ComponentEvent<?>> eventType)	Gets a map of event data expression (for DomListenerRegistration.addEventData(String) ) to Java type, with the same order as the parameters for the event constructor (as returned by getEventConstructor(Class)).
static List<String>	getListenerEventData(Class<? extends ComponentEvent<?>> eventType)	Gets the event data expressions to add to a DOM listener registration for the given event type, with expressions for components and elements mapped like DomListenerRegistration.addEventDataElement(String) does.
static boolean	isDomEventConstructor(Constructor<?> constructor)	Checks if the given constructor can be used when firing a ComponentEvent based on a DomEvent.

Methods inherited from class java.lang.Object

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

Method Details

getEventDataExpressions

public static LinkedHashMap<String,Class<?>> getEventDataExpressions(Class<? extends ComponentEvent<?>> eventType)

Gets a map of event data expression (for DomListenerRegistration.addEventData(String) ) to Java type, with the same order as the parameters for the event constructor (as returned by getEventConstructor(Class)).

Caches values and automatically uses the cached values when available.

Parameters:

eventType - the component event type

Returns:

a map of event expressions, ordered in constructor parameter order

getListenerEventData

public static List<String> getListenerEventData(Class<? extends ComponentEvent<?>> eventType)

Gets the event data expressions to add to a DOM listener registration for the given event type, with expressions for components and elements mapped like DomListenerRegistration.addEventDataElement(String) does.

The same unmodifiable list is returned for every call so that all listeners of the event type can share it, see DomListenerRegistration.addEventData(List).

Parameters:

eventType - the component event type

Returns:

an unmodifiable list of event data expressions for a DOM listener registration

getEventConstructor

public static <T extends ComponentEvent<?>>
Constructor<T> getEventConstructor(Class<T> eventType)

Gets the constructor to use for firing a component event, of the given type, based on a DOM event.

Type Parameters:

T - the event type

Parameters:

eventType - the event type

Returns:

the constructor to use when creating an event from a DOM event

Throws:

IllegalArgumentException - if no suitable constructor was found

isDomEventConstructor

public static boolean isDomEventConstructor(Constructor<?> constructor)

Checks if the given constructor can be used when firing a ComponentEvent based on a DomEvent.

Parameters:

constructor - the constructor to check

Returns:

true if the constructor can be used, false otherwise