com.sun.javafx.event.EventHandlerManager Maven / Gradle / Ivy
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package com.sun.javafx.event;
import java.util.HashMap;
import java.util.Map;
import javafx.event.Event;
import javafx.event.EventHandler;
import javafx.event.EventType;
/**
* An {@code EventDispatcher} which allows user event handler / filter
* registration and when used in an event dispatch chain it forwards received
* events to the appropriate registered handlers / filters.
*/
public class EventHandlerManager extends BasicEventDispatcher {
private final Map,
CompositeEventHandler> eventHandlerMap;
private final Object eventSource;
public EventHandlerManager(final Object eventSource) {
this.eventSource = eventSource;
eventHandlerMap = new HashMap<>();
}
/**
* Registers an event handler in {@code EventHandlerManager}.
*
* @param the specific event class of the handler
* @param eventType the type of the events to receive by the handler
* @param eventHandler the handler to register
* @throws NullPointerException if the event type or handler is null
*/
public final void addEventHandler(
final EventType eventType,
final EventHandler eventHandler) {
validateEventType(eventType);
validateEventHandler(eventHandler);
final CompositeEventHandler compositeEventHandler =
createGetCompositeEventHandler(eventType);
compositeEventHandler.addEventHandler(eventHandler);
}
/**
* Unregisters a previously registered event handler.
*
* @param the specific event class of the handler
* @param eventType the event type from which to unregister
* @param eventHandler the handler to unregister
* @throws NullPointerException if the event type or handler is null
*/
public final void removeEventHandler(
final EventType eventType,
final EventHandler eventHandler) {
validateEventType(eventType);
validateEventHandler(eventHandler);
final CompositeEventHandler compositeEventHandler =
(CompositeEventHandler) eventHandlerMap.get(eventType);
if (compositeEventHandler != null) {
compositeEventHandler.removeEventHandler(eventHandler);
}
}
/**
* Registers an event filter in {@code EventHandlerManager}.
*
* @param the specific event class of the filter
* @param eventType the type of the events to receive by the filter
* @param eventFilter the filter to register
* @throws NullPointerException if the event type or filter is null
*/
public final void addEventFilter(
final EventType eventType,
final EventHandler eventFilter) {
validateEventType(eventType);
validateEventFilter(eventFilter);
final CompositeEventHandler compositeEventHandler =
createGetCompositeEventHandler(eventType);
compositeEventHandler.addEventFilter(eventFilter);
}
/**
* Unregisters a previously registered event filter.
*
* @param the specific event class of the filter
* @param eventType the event type from which to unregister
* @param eventFilter the filter to unregister
* @throws NullPointerException if the event type or filter is null
*/
public final void removeEventFilter(
final EventType eventType,
final EventHandler eventFilter) {
validateEventType(eventType);
validateEventFilter(eventFilter);
final CompositeEventHandler compositeEventHandler =
(CompositeEventHandler) eventHandlerMap.get(eventType);
if (compositeEventHandler != null) {
compositeEventHandler.removeEventFilter(eventFilter);
}
}
/**
* Sets the specified singleton handler. There can only be one such handler
* specified at a time.
*
* @param the specific event class of the handler
* @param eventType the event type to associate with the given eventHandler
* @param eventHandler the handler to register, or null to unregister
* @throws NullPointerException if the event type is null
*/
public final void setEventHandler(
final EventType eventType,
final EventHandler eventHandler) {
validateEventType(eventType);
CompositeEventHandler compositeEventHandler =
(CompositeEventHandler) eventHandlerMap.get(eventType);
if (compositeEventHandler == null) {
if (eventHandler == null) {
return;
}
compositeEventHandler = new CompositeEventHandler<>();
eventHandlerMap.put(eventType, compositeEventHandler);
}
compositeEventHandler.setEventHandler(eventHandler);
}
public final EventHandler getEventHandler(
final EventType eventType) {
final CompositeEventHandler compositeEventHandler =
(CompositeEventHandler) eventHandlerMap.get(eventType);
return (compositeEventHandler != null)
? compositeEventHandler.getEventHandler()
: null;
}
@Override
public final Event dispatchCapturingEvent(Event event) {
EventType eventType = event.getEventType();
do {
event = dispatchCapturingEvent(eventType, event);
eventType = eventType.getSuperType();
} while (eventType != null);
return event;
}
@Override
public final Event dispatchBubblingEvent(Event event) {
EventType eventType = event.getEventType();
do {
event = dispatchBubblingEvent(eventType, event);
eventType = eventType.getSuperType();
} while (eventType != null);
return event;
}
private CompositeEventHandler
createGetCompositeEventHandler(final EventType eventType) {
CompositeEventHandler compositeEventHandler =
(CompositeEventHandler) eventHandlerMap.get(eventType);
if (compositeEventHandler == null) {
compositeEventHandler = new CompositeEventHandler<>();
eventHandlerMap.put(eventType, compositeEventHandler);
}
return compositeEventHandler;
}
protected Object getEventSource() {
return eventSource;
}
private Event dispatchCapturingEvent(
final EventType handlerType, Event event) {
final CompositeEventHandler compositeEventHandler =
eventHandlerMap.get(handlerType);
if (compositeEventHandler != null && compositeEventHandler.hasFilter()) {
event = fixEventSource(event, eventSource);
compositeEventHandler.dispatchCapturingEvent(event);
}
return event;
}
private Event dispatchBubblingEvent(
final EventType handlerType, Event event) {
final CompositeEventHandler compositeEventHandler =
eventHandlerMap.get(handlerType);
if (compositeEventHandler != null && compositeEventHandler.hasHandler()) {
event = fixEventSource(event, eventSource);
compositeEventHandler.dispatchBubblingEvent(event);
}
return event;
}
private static Event fixEventSource(final Event event,
final Object eventSource) {
return (event.getSource() != eventSource)
? event.copyFor(eventSource, event.getTarget())
: event;
}
private static void validateEventType(final EventType eventType) {
if (eventType == null) {
throw new NullPointerException("Event type must not be null");
}
}
private static void validateEventHandler(
final EventHandler eventHandler) {
if (eventHandler == null) {
throw new NullPointerException("Event handler must not be null");
}
}
private static void validateEventFilter(
final EventHandler eventFilter) {
if (eventFilter == null) {
throw new NullPointerException("Event filter must not be null");
}
}
}
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