Class EventFactory
 It's highly recommended that the event is defined at compile time, if the
 field layout is known, so the Java Virtual Machine (JVM) can optimize the
 code, possibly remove all instrumentation if Flight Recorder is inactive or
 if the enabled setting for this event is set to false.
 
 To define an event at compile time, see Event.
 
 The following example shows how to implement a dynamic Event class.
 
List<ValueDescriptor> fields = new ArrayList<>();
List<AnnotationElement> messageAnnotations = Collections.singletonList(new AnnotationElement(Label.class, "Message"));
fields.add(new ValueDescriptor(String.class, "message", messageAnnotations));
List<AnnotationElement> numberAnnotations = Collections.singletonList(new AnnotationElement(Label.class, "Number"));
fields.add(new ValueDescriptor(int.class, "number", numberAnnotations));
String[] category = { "Example", "Getting Started" };
List<AnnotationElement> eventAnnotations = new ArrayList<>();
eventAnnotations.add(new AnnotationElement(Name.class, "com.example.HelloWorld"));
eventAnnotations.add(new AnnotationElement(Label.class, "Hello World"));
eventAnnotations.add(new AnnotationElement(Description.class, "Helps programmer getting started"));
eventAnnotations.add(new AnnotationElement(Category.class, category));
EventFactory f = EventFactory.create(eventAnnotations, fields);
Event event = f.newEvent();
event.set(0, "hello, world!");
event.set(1, 4711);
event.commit();
- Since:
- 9
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Method SummaryModifier and TypeMethodDescriptionstatic EventFactorycreate(List<AnnotationElement> annotationElements, List<ValueDescriptor> fields) Creates anEventFactoryobject.Returns the event type that is associated with this event factory.newEvent()Instantiates an event, so it can be populated with data and written to the Flight Recorder system.voidregister()Registers an unregistered event.voidUnregisters the event that is associated with this event factory.
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Method Details- 
createpublic static EventFactory create(List<AnnotationElement> annotationElements, List<ValueDescriptor> fields) Creates anEventFactoryobject.The order of the value descriptors specifies the index to use when setting event values. - Parameters:
- annotationElements- list of annotation elements that describes the annotations on the event, not- null
- fields- list of descriptors that describes the fields of the event, not- null
- Returns:
- event factory, not null
- Throws:
- IllegalArgumentException- if the input is not valid. For example, input might not be valid if the field type or name is not valid in the Java language or an annotation element references a type that can't be found.
- See Also:
 
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newEventInstantiates an event, so it can be populated with data and written to the Flight Recorder system.Use the Event.set(int, Object)method to set a value.- Returns:
- an event instance, not null
 
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getEventTypeReturns the event type that is associated with this event factory.- Returns:
- event type that is associated with this event factory, not
         null
- Throws:
- IllegalStateException- if the event factory is created with the- Registered(false)annotation and the event class is not manually registered before the invocation of this method
 
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registerpublic void register()Registers an unregistered event.By default, the event class associated with this event factory is registered when the event factory is created, unless the event has the Registeredannotation.A registered event class can write data to Flight Recorder and event metadata can be obtained by invoking FlightRecorder.getEventTypes().If the event class associated with this event factory is already registered, the call to this method is ignored. - See Also:
 
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unregisterpublic void unregister()Unregisters the event that is associated with this event factory.A unregistered event class can't write data to Flight Recorder and event metadata can't be obtained by invoking FlightRecorder.getEventTypes().If the event class associated with this event factory is not already registered, the call to this method is ignored. - See Also:
 
 
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