001/**
002 * Copyright 2005-2014 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.rice.kcb.service;
017
018import java.lang.reflect.Proxy;
019
020import org.apache.log4j.Logger;
021import org.kuali.rice.kcb.util.BeanFactoryInvocationHandler;
022import org.springframework.beans.factory.BeanFactory;
023
024/**
025 * Class that holds a singleton reference to KCBServiceLocator
026 * @author Kuali Rice Team (rice.collab@kuali.org)
027 */
028public class GlobalKCBServiceLocator {
029    private static final Logger LOG = Logger.getLogger(GlobalKCBServiceLocator.class);
030
031    /**
032     * The KCBServiceLocator singleton
033     */
034    private static KCBServiceLocator locator;
035
036    /**
037     * The global initializer that constructs the KCBServiceLocator singleton
038     * @param beanFactory the beanFactory from which to construct the KCBServiceLocator
039     */
040    public static synchronized void init(BeanFactory beanFactory) {
041        //        LOG.error("INITIALIZING", new Exception());
042        if (locator != null) {
043            throw new IllegalStateException("GlobalKCBServiceLocator already initialized");
044        }
045
046        locator = (KCBServiceLocator) Proxy.newProxyInstance(GlobalKCBServiceLocator.class.getClassLoader(),
047                new Class[] { KCBServiceLocator.class },
048                new BeanFactoryInvocationHandler(beanFactory));
049    }
050
051    /**
052     * Returns whether the GlobalKCBServiceLocator has already been initialized (classloader scoped)
053     * @return whether the GlobalKCBServiceLocator has already been initialized (classloader scoped)
054     */
055    public static synchronized boolean isInitialized() {
056        return locator != null;
057    }
058
059    /**
060     * Un-sets the KCBServiceLocator singleton, in order to fulfill a "lifecycle"
061     * contract (whereby init may be called again in the same class loader), specifically for
062     * unit tests.
063     */
064    public static synchronized void destroy() {
065        //LOG.debug("DESTROYING", new Exception());
066        locator = null;
067    }
068
069    /**
070     * Returns the KCBServiceLocator singleton
071     * @return the KCBServiceLocator singleton
072     */
073    public static synchronized KCBServiceLocator getInstance() {
074        return locator;
075    }
076}