org.killbill.billing.util.security.AnnotationHierarchicalResolver Maven / Gradle / Ivy
/*
* Copyright 2010-2013 Ning, Inc.
*
* Ning licenses this file to you under the Apache License, version 2.0
* (the "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package org.killbill.billing.util.security;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.util.Map;
import java.util.WeakHashMap;
import org.apache.shiro.aop.AnnotationResolver;
import org.apache.shiro.aop.MethodInvocation;
public class AnnotationHierarchicalResolver implements AnnotationResolver {
@Override
public Annotation getAnnotation(final MethodInvocation mi, final Class clazz) {
return getAnnotationFromMethod(mi.getMethod(), clazz);
}
public Annotation getAnnotationFromMethod(final Method method, final Class clazz) {
return findAnnotation(method, clazz);
}
// The following comes from spring-core (AnnotationUtils) to handle annotations on interfaces
/**
* Get a single {@link Annotation} of annotationType from the supplied {@link java.lang.reflect.Method},
* traversing its super methods if no annotation can be found on the given method itself.
* Annotations on methods are not inherited by default, so we need to handle this explicitly.
*
* @param method the method to look for annotations on
* @param annotationType the annotation class to look for
* @return the annotation found, or null if none found
*/
public static A findAnnotation(final Method method, final Class annotationType) {
A annotation = getAnnotation(method, annotationType);
Class cl = method.getDeclaringClass();
if (annotation == null) {
annotation = searchOnInterfaces(method, annotationType, cl.getInterfaces());
}
while (annotation == null) {
cl = cl.getSuperclass();
if (cl == null || cl == Object.class) {
break;
}
try {
final Method equivalentMethod = cl.getDeclaredMethod(method.getName(), method.getParameterTypes());
annotation = getAnnotation(equivalentMethod, annotationType);
if (annotation == null) {
annotation = searchOnInterfaces(method, annotationType, cl.getInterfaces());
}
} catch (NoSuchMethodException ex) {
// We're done...
}
}
return annotation;
}
/**
* Get a single {@link Annotation} of annotationType from the supplied {@link Method}.
*
* @param method the method to look for annotations on
* @param annotationType the annotation class to look for
* @return the annotations found
*/
public static A getAnnotation(final Method method, final Class annotationType) {
A ann = method.getAnnotation(annotationType);
if (ann == null) {
for (final Annotation metaAnn : method.getAnnotations()) {
ann = metaAnn.annotationType().getAnnotation(annotationType);
if (ann != null) {
break;
}
}
}
return ann;
}
private static A searchOnInterfaces(final Method method, final Class annotationType, final Class[] ifcs) {
A annotation = null;
for (final Class iface : ifcs) {
if (isInterfaceWithAnnotatedMethods(iface)) {
try {
final Method equivalentMethod = iface.getMethod(method.getName(), method.getParameterTypes());
annotation = getAnnotation(equivalentMethod, annotationType);
} catch (NoSuchMethodException ex) {
// Skip this interface - it doesn't have the method...
}
if (annotation != null) {
break;
}
}
}
return annotation;
}
private static final Map, Boolean> annotatedInterfaceCache = new WeakHashMap, Boolean>();
private static boolean isInterfaceWithAnnotatedMethods(final Class iface) {
synchronized (annotatedInterfaceCache) {
final Boolean flag = annotatedInterfaceCache.get(iface);
if (flag != null) {
return flag;
}
boolean found = false;
for (final Method ifcMethod : iface.getMethods()) {
if (ifcMethod.getAnnotations().length > 0) {
found = true;
break;
}
}
annotatedInterfaceCache.put(iface, found);
return found;
}
}
}