PersistenceContextScanner.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 1997-2013 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */
package com.sun.faces.application.annotation;

import com.sun.faces.util.Util;
import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import javax.persistence.PersistenceContext;

/**
 * <code>Scanner</code> implementation responsible for {@link PersistenceContext} annotations.
 */
class PersistenceContextScanner implements Scanner {

    /**
     * Get the annotation we handle.
     *
     * @return the annotation we handle.
     */
    @Override
    public Class<? extends Annotation> getAnnotation() {
        return PersistenceContext.class;
    }

    /**
     * Scan the specified class for the given annotation.
     *
     * @param clazz the class.
     * @return the runtime annotation handler.
     * @todo Make sure we get all the fields, handle method and class based injection, handle PersistenceContexts.
     */
    @Override
    public RuntimeAnnotationHandler scan(Class<?> clazz) {
        Util.notNull("clazz", clazz);
        PersistenceContextHandler handler = null;

        ArrayList<PersistenceContext> fieldAnnotations = new ArrayList<>();
        ArrayList<Field> fields = new ArrayList<>();

        for (Field field : clazz.getDeclaredFields()) {
            PersistenceContext fieldAnnotation = field.getAnnotation(PersistenceContext.class);
            if (fieldAnnotation != null) {
                fieldAnnotations.add(fieldAnnotation);
                fields.add(field);
            }
        }
        
        ArrayList<PersistenceContext> methodAnnotations = new ArrayList<>();
        ArrayList<Method> methods = new ArrayList<>();
        for (Method method : clazz.getDeclaredMethods()) {
            PersistenceContext methodAnnotation = method.getAnnotation(PersistenceContext.class);
            if (methodAnnotation != null) {
                methodAnnotations.add(methodAnnotation);
                methods.add(method);
            }
        }
        
        if (!fieldAnnotations.isEmpty() || !methodAnnotations.isEmpty()) {
            handler = new PersistenceContextHandler(
                    methods.toArray(new Method[0]), methodAnnotations.toArray(new PersistenceContext[0]),
                    fields.toArray(new Field[0]), fieldAnnotations.toArray(new PersistenceContext[0]));
        }
        return handler;
    }
}