com.db2eshop.governance.spring.ApplicationContextObserver.java Source code

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Here is the source code for com.db2eshop.governance.spring.ApplicationContextObserver.java

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/*
 * Copyright 2012 Denis Neuling, Dennis Wieding, Mateusz Wozniak
 * 
 * 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.db2eshop.governance.spring;

import java.util.Observable;

import org.apache.log4j.Logger;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.context.event.ContextRefreshedEvent;

import com.db2eshop.governance.spring.event.ContextEvent;

/**
 * <p>ApplicationContextObserver class.</p>
 *
 * @author Denis Neuling (denisneuling@gmail.com)
 * 
 */
@SuppressWarnings("rawtypes")
public class ApplicationContextObserver extends Observable
        implements BeanPostProcessor, ApplicationContextAware, ApplicationListener {
    private final Logger log = Logger.getLogger(this.getClass());
    private static ApplicationContextObserver INSTANCE;
    private volatile boolean refreshed = false;

    /**
     * <p>getInstance.</p>
     *
     * @return a {@link com.db2eshop.governance.spring.ApplicationContextObserver} object.
     */
    public static ApplicationContextObserver getInstance() {
        if (INSTANCE == null) {
            INSTANCE = new ApplicationContextObserver();
        }
        return INSTANCE;
    }

    private ApplicationContext applicationContext;

    /** {@inheritDoc} */
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }

    /** {@inheritDoc} */
    @Override
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        log.info(String.format("On %s Bean {%s} initialized.", applicationContext.getDisplayName(), beanName));

        this.setChanged();
        this.notifyObservers(new ContextEvent(beanName));

        return bean;
    }

    /** {@inheritDoc} */
    @Override
    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
        return bean;
    }

    /** {@inheritDoc} */
    @Override
    public void onApplicationEvent(ApplicationEvent event) {
        if (event instanceof ContextRefreshedEvent) {
            this.setChanged();
            this.notifyObservers(new ContextEvent(ContextEvent.State.FINISHED));
            refreshed = true;
        }
    }

    /**
     * <p>isRefreshed.</p>
     *
     * @return a boolean.
     */
    public boolean isRefreshed() {
        return refreshed;
    }

    /**
     * <p>Setter for the field <code>refreshed</code>.</p>
     *
     * @param refreshed a boolean.
     */
    public void setRefreshed(boolean refreshed) {
        this.refreshed = refreshed;
    }
}