com.example.config.BeanCountingApplicationListener.java Source code

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Here is the source code for com.example.config.BeanCountingApplicationListener.java

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/*
 * Copyright 2016-2017 the original author or authors.
 *
 * 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.example.config;

import java.lang.management.ManagementFactory;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeansException;
import org.springframework.boot.context.event.ApplicationReadyEvent;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ApplicationListener;
import org.springframework.context.ConfigurableApplicationContext;

/**
 * @author Dave Syer
 *
 */
public class BeanCountingApplicationListener
        implements ApplicationListener<ApplicationReadyEvent>, ApplicationContextAware {

    private static Log logger = LogFactory.getLog(BeanCountingApplicationListener.class);
    private ApplicationContext context;

    @Override
    public void setApplicationContext(ApplicationContext context) throws BeansException {
        this.context = context;
    }

    @SuppressWarnings("resource")
    @Override
    public void onApplicationEvent(ApplicationReadyEvent event) {
        if (!event.getApplicationContext().equals(this.context)) {
            return;
        }
        int count = 0;
        ConfigurableApplicationContext context = event.getApplicationContext();
        String id = context.getId();
        List<String> names = new ArrayList<>();
        while (context != null) {
            count += context.getBeanDefinitionCount();
            names.addAll(Arrays.asList(context.getBeanDefinitionNames()));
            context = (ConfigurableApplicationContext) context.getParent();
        }
        logger.info("Bean count: " + id + "=" + count);
        logger.debug("Bean names: " + id + "=" + names);
        try {
            logger.info("Class count: " + id + "="
                    + ManagementFactory.getClassLoadingMXBean().getTotalLoadedClassCount());
        } catch (Exception e) {
        }
    }

}