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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package org.graalvm.util;
import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;
Wrapper class for annotation access that defends against
https://bugs.openjdk.java.net/browse/JDK-7183985: when an annotation declares a Class array
parameter and one of the referenced classes is not present on the classpath parsing the
annotations will result in an ArrayStoreException instead of caching of a
TypeNotPresentExceptionProxy. This is a problem in JDK8 but was fixed in JDK11+. This wrapper
class also defends against incomplete class path issues. If the element for which annotations are
queried is a JMVCI value, i.e., a HotSpotResolvedJavaField, or HotSpotResolvedJavaMethod, the
annotations are read via HotSpotJDKReflection using the
getFieldAnnotation()/getMethodAnnotation() methods which first construct the field/method object
via CompilerToVM.asReflectionField()/CompilerToVM.asReflectionExecutable() which eagerly try to
resolve the types referenced in the element signature. If a field declared type or a method
return type is missing then JVMCI throws a NoClassDefFoundError.
/**
* Wrapper class for annotation access that defends against
* https://bugs.openjdk.java.net/browse/JDK-7183985: when an annotation declares a Class<?> array
* parameter and one of the referenced classes is not present on the classpath parsing the
* annotations will result in an ArrayStoreException instead of caching of a
* TypeNotPresentExceptionProxy. This is a problem in JDK8 but was fixed in JDK11+. This wrapper
* class also defends against incomplete class path issues. If the element for which annotations are
* queried is a JMVCI value, i.e., a HotSpotResolvedJavaField, or HotSpotResolvedJavaMethod, the
* annotations are read via HotSpotJDKReflection using the
* getFieldAnnotation()/getMethodAnnotation() methods which first construct the field/method object
* via CompilerToVM.asReflectionField()/CompilerToVM.asReflectionExecutable() which eagerly try to
* resolve the types referenced in the element signature. If a field declared type or a method
* return type is missing then JVMCI throws a NoClassDefFoundError.
*/
public final class GuardedAnnotationAccess {
public static boolean isAnnotationPresent(AnnotatedElement element, Class<? extends Annotation> annotationClass) {
return getAnnotation(element, annotationClass) != null;
}
public static <T extends Annotation> T getAnnotation(AnnotatedElement element, Class<T> annotationType) {
try {
return element.getAnnotation(annotationType);
} catch (ArrayStoreException | NoClassDefFoundError e) {
/*
* Returning null essentially means that the element doesn't declare the annotationType,
* but we cannot know that since the annotation parsing failed. However, this allows us
* to defend against crashing the image builder if the above JDK bug is encountered in
* user code or if the user code references types missing from the classpath.
*/
return null;
}
}
public static Annotation[] getAnnotations(AnnotatedElement element) {
try {
return element.getAnnotations();
} catch (ArrayStoreException | NoClassDefFoundError e) {
/*
* Returning an empty array essentially means that the element doesn't declare any
* annotations, but we know that it is not true since the reason the annotation parsing
* failed is because some annotation referenced a missing class. However, this allows us
* to defend against crashing the image builder if the above JDK bug is encountered in
* user code or if the user code references types missing from the classpath.
*/
return new Annotation[0];
}
}
public static <T extends Annotation> T getDeclaredAnnotation(AnnotatedElement element, Class<T> annotationType) {
try {
return element.getDeclaredAnnotation(annotationType);
} catch (ArrayStoreException | NoClassDefFoundError e) {
/*
* Returning null essentially means that the element doesn't declare the annotationType,
* but we cannot know that since the annotation parsing failed. However, this allows us
* to defend against crashing the image builder if the above JDK bug is encountered in
* user code or if the user code references types missing from the classpath.
*/
return null;
}
}
public static Annotation[] getDeclaredAnnotations(AnnotatedElement element) {
try {
return element.getDeclaredAnnotations();
} catch (ArrayStoreException | NoClassDefFoundError e) {
/*
* Returning an empty array essentially means that the element doesn't declare any
* annotations, but we know that it is not true since the reason the annotation parsing
* failed is because it at least one annotation referenced a missing class. However,
* this allows us to defend against crashing the image builder if the above JDK bug is
* encountered in user code or if the user code references types missing from the
* classpath.
*/
return new Annotation[0];
}
}
}