Module jakarta.cdi
Package jakarta.enterprise.inject.spi

Interface ObserverMethod<T>

  • Type Parameters:
    T - the event type
    All Superinterfaces:
    Prioritized
    public interface ObserverMethod<T>
extends Prioritized

    Represents an observer method of an enabled bean. Defines everything the container needs to know about an observer method.

    If a custom implementation of this interface does not override either notify(Object) or notify(EventContext), the container automatically detects the problem and treats it as a definition error.

    Author:
    Gavin King, David Allen, Mark Paluch, Antoine Sabot-Durand

    • Method Detail

      • getBeanClass

        java.lang.Class<?> getBeanClass()

        Obtains the class of the type that declares the observer method.

        Returns:
        the defining class

      • getDeclaringBean

        default Bean<?> getDeclaringBean()

        Obtains the bean that declares the observer method. For synthetic observers, the return value is undefined.

        For the sake of compatibility with existing custom ObserverMethod implementations, this method by default returns null.

        Returns:
        the declaring bean

      • getObservedType

        java.lang.reflect.Type getObservedType()
        Obtains the observed event type.
        Returns:
        the observed event type

      • getObservedQualifiers

        java.util.Set<java.lang.annotation.Annotation> getObservedQualifiers()
        Obtains the set of observed event qualifiers.
        Returns:
        the observed event qualifiers

      • getReception

        Reception getReception()
        Obtains the specified Reception for the observer method. This indicates if the observer is conditional or not.
        Returns:
        the Reception

      • getPriority

        default int getPriority()
        The priority that will be used by the container to determine the notification order in which event observer methods are invoked.
        Specified by:
        getPriority in interface Prioritized
        Returns:
        The priority that will be used by the container to determine the notification order in which event observer methods are invoked.
        Since:
        2.0

      • notify

        default void notify​(T event)

        Calls the observer method, passing the given event object.

        The implementation of this method for a custom observer method is responsible for deciding whether to call the method if the getReception() returns Reception.IF_EXISTS.

        Parameters:
        event - the event object

      • notify

        default void notify​(EventContext<T> eventContext)
        Calls the observer method, passing the given event context.

        The container should always call this method, but the default implementation delegates to notify(Object).

        The implementation of this method for a custom observer method is responsible for deciding whether to call the method if the getReception() returns Reception.IF_EXISTS.

        Parameters:
        eventContext - EventContext used to notify observers

      • isAsync

        default boolean isAsync()

        Determines if this observer method is asynchronous

        Returns:
        returns true if the method is an asynchronous observer method (i.e. defined with ObservesAsync), otherwise returns false