001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2008-2011 SonarSource
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.api.utils;
021    
022    import org.apache.commons.lang.ClassUtils;
023    
024    import java.util.List;
025    
026    /**
027     * A utility class for annotations
028     *
029     * @since 1.11
030     */
031    public final class AnnotationUtils {
032    
033      private AnnotationUtils() {
034      }
035    
036      /**
037       * Searches for a class annotation. All inheritance tree is analysed.
038       */
039      public static <A> A getClassAnnotation(final Object object, final Class<A> annotationClass) {
040        Class initialClass = (object instanceof Class ? (Class) object : object.getClass());
041        A result = null;
042        Class aClass=initialClass;
043        while (aClass != null && result == null) {
044          result = (A)aClass.getAnnotation(annotationClass);
045          aClass = aClass.getSuperclass();
046        }
047    
048        if (result==null) {
049          List<Class> interfaces = ClassUtils.getAllInterfaces(initialClass);
050          for (Class anInterface : interfaces) {
051            result = (A)anInterface.getAnnotation(annotationClass);
052            if (result!=null) {
053              break;
054            }
055          }
056        }
057        return result;
058      }
059    }