/*
* Copyright 2002-2006,2009 The Apache Software Foundation.
*
* Licensed 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 com.opensymphony.xwork2.util;
import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* <code>AnnotationUtils</code>
*
* Various utility methods dealing with annotations
*
* @author Rainer Hermanns
* @author Zsolt Szasz, zsolt at lorecraft dot com
* @author Dan Oxlade, dan d0t oxlade at gmail d0t c0m
* @version $Id$
*/
public class AnnotationUtils {
private static final Pattern SETTER_PATTERN = Pattern.compile("set([A-Z][A-Za-z0-9]*)$");
private static final Pattern GETTER_PATTERN = Pattern.compile("(get|is|has)([A-Z][A-Za-z0-9]*)$");
/**
* Adds all fields with the specified Annotation of class clazz and its superclasses to allFields
*
* @param annotationClass
* @param clazz
* @param allFields
*/
public static void addAllFields(Class<? extends Annotation> annotationClass, Class clazz, List<Field> allFields) {
if (clazz == null) {
return;
}
Field[] fields = clazz.getDeclaredFields();
for (Field field : fields) {
Annotation ann = field.getAnnotation(annotationClass);
if (ann!=null) {
allFields.add(field);
}
}
addAllFields(annotationClass, clazz.getSuperclass(), allFields);
}
/**
* Adds all methods with the specified Annotation of class clazz and its superclasses to allFields
*
* @param annotationClass
* @param clazz
* @param allMethods
*/
public static void addAllMethods(Class<? extends Annotation> annotationClass, Class clazz, List<Method> allMethods) {
if (clazz == null) {
return;
}
Method[] methods = clazz.getDeclaredMethods();
for (Method method : methods) {
Annotation ann = method.getAnnotation(annotationClass);
if (ann!=null) {
allMethods.add(method);
}
}
addAllMethods(annotationClass, clazz.getSuperclass(), allMethods);
}
/**
*
* @param clazz
* @param allInterfaces
*/
public static void addAllInterfaces(Class clazz, List<Class> allInterfaces) {
if (clazz == null) {
return;
}
Class[] interfaces = clazz.getInterfaces();
allInterfaces.addAll(Arrays.asList(interfaces));
addAllInterfaces(clazz.getSuperclass(), allInterfaces);
}
/**
* For the given <code>Class</code> get a collection of the the {@link AnnotatedElement}s
* that match the given <code>annotation</code>s or if no <code>annotation</code>s are
* specified then return all of the annotated elements of the given <code>Class</code>.
* Includes only the method level annotations.
*
* @param clazz The {@link Class} to inspect
* @param annotation the {@link Annotation}s to find
* @return A {@link Collection}<{@link AnnotatedElement}> containing all of the
* method {@link AnnotatedElement}s matching the specified {@link Annotation}s
*/
public static Collection<Method> getAnnotatedMethods(Class clazz, Class<? extends Annotation>... annotation){
Collection<Method> toReturn = new HashSet<Method>();
for(Method m : clazz.getMethods()){
if( ArrayUtils.isNotEmpty(annotation) && isAnnotatedBy(m, annotation) ){
toReturn.add(m);
}else if( ArrayUtils.isEmpty(annotation) && ArrayUtils.isNotEmpty(m.getAnnotations())){
toReturn.add(m);
}
}
return toReturn;
}
/**
* Varargs version of <code>AnnotatedElement.isAnnotationPresent()</code>
* @see AnnotatedElement
*/
public static boolean isAnnotatedBy(AnnotatedElement annotatedElement, Class<? extends Annotation>... annotation) {
if(ArrayUtils.isEmpty(annotation)) return false;
for( Class<? extends Annotation> c : annotation ){
if( annotatedElement.isAnnotationPresent(c) ) return true;
}
return false;
}
/**
* Returns the property name for a method.
* This method is independent from property fields.
*
* @param method The method to get the property name for.
* @return the property name for given method; null if non could be resolved.
*/
public static String resolvePropertyName(Method method) {
Matcher matcher = SETTER_PATTERN.matcher(method.getName());
if (matcher.matches() && method.getParameterTypes().length == 1) {
String raw = matcher.group(1);
return raw.substring(0, 1).toLowerCase() + raw.substring(1);
}
matcher = GETTER_PATTERN.matcher(method.getName());
if (matcher.matches() && method.getParameterTypes().length == 0) {
String raw = matcher.group(2);
return raw.substring(0, 1).toLowerCase() + raw.substring(1);
}
return null;
}
/**
* Returns the annotation on the given class or the package of the class. This searchs up the
* class hierarchy and the package hierarchy for the closest match.
*
* @param klass The class to search for the annotation.
* @param annotationClass The Class of the annotation.
* @return The annotation or null.
*/
public static <T extends Annotation> T findAnnotation(Class<?> klass, Class<T> annotationClass) {
T ann = klass.getAnnotation(annotationClass);
while (ann == null && klass != null) {
ann = klass.getAnnotation(annotationClass);
if (ann == null)
ann = klass.getPackage().getAnnotation(annotationClass);
if (ann == null) {
klass = klass.getSuperclass();
if (klass != null ) {
ann = klass.getAnnotation(annotationClass);
}
}
}
return ann;
}
}