org.graalvm.nativeimage

Class AnnotationAccess

java.lang.Object

org.graalvm.nativeimage.AnnotationAccess

public final class AnnotationAccess
extends Object

This class provides methods to query annotation information on AnnotatedElements while trying to prevent, at image build time, side-effecting changes that impact the analysis results. The getAnnotation implementation in the JDK for Class, Field, and Method initializes the classes of all annotations present on that element, not just the class of the queried annotation. This leads to problems when not all annotation classes are present on the classpath/modulepath: querying an annotation whose class is present can fail with an exception because not all annotation classes are present. When this class's methods are called at image build time, then the minimal amount of class initialization is done: AnnotationAccess.getAnnotation(java.lang.reflect.AnnotatedElement, java.lang.Class<T>) only initializes the queried annotation class (when the annotation is actually present and therefore instantiated); AnnotationAccess.isAnnotationPresent(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>) and AnnotationAccess.getAnnotationTypes(java.lang.reflect.AnnotatedElement) do not initialize any classes. When methods of this class are called not at image build time, i.e., at image run time or during the execution of a Java application not involving native image, then the JDK method to query the annotation is invoked. In these cases, there is no difference to the class initialization behavior of the JDK. Note that there is intentionally no `getAnnotations` method to query all annotations: all annotation classes must be initialized anyways by this method, so the JDK method can be invoke directly. In the image generator it should be generally avoided to use `getAnnotations`.

Since:

22.3

Method Summary

Modifier and Type	Method and Description
static <T extends Annotation> T	getAnnotation(AnnotatedElement element, Class<T> annotationType) Implementation of AnnotatedElement.getAnnotation(Class) .
static Class<? extends Annotation>[]	getAnnotationTypes(AnnotatedElement element) Implementation for retrieving all Annotation.annotationType()s for a element.
static boolean	isAnnotationPresent(AnnotatedElement element, Class<? extends Annotation> annotationClass) Implementation of AnnotatedElement.isAnnotationPresent(Class).

Methods inherited from class java.lang.Object

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

Method Detail

isAnnotationPresent

public static boolean isAnnotationPresent(AnnotatedElement element,
                                          Class<? extends Annotation> annotationClass)

Implementation of AnnotatedElement.isAnnotationPresent(Class).

Since:

22.3

getAnnotation

public static <T extends Annotation> T getAnnotation(AnnotatedElement element,
                                                     Class<T> annotationType)

Implementation of AnnotatedElement.getAnnotation(Class) .

Since:

22.3

getAnnotationTypes

public static Class<? extends Annotation>[] getAnnotationTypes(AnnotatedElement element)

Implementation for retrieving all Annotation.annotationType()s for a element.

Since:

22.3