com.example.config.StartupApplicationListener.java Source code

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Here is the source code for com.example.config.StartupApplicationListener.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.reflect.Method;
import java.util.LinkedHashSet;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeansException;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.SpringBootConfiguration;
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.core.annotation.AnnotatedElementUtils;
import org.springframework.util.ClassUtils;
import org.springframework.util.ReflectionUtils;

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

    public static final String MARKER = "Benchmark app started";
    private static Log logger = LogFactory.getLog(StartupApplicationListener.class);
    private ApplicationContext context;

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

    @Override
    public void onApplicationEvent(ApplicationReadyEvent event) {
        if (!event.getApplicationContext().equals(this.context)) {
            return;
        }
        if (isSpringBootApplication(sources(event))) {
            try {
                logger.info(MARKER);
            } catch (Exception e) {
            }
        }
    }

    private boolean isSpringBootApplication(Set<Class<?>> sources) {
        for (Class<?> source : sources) {
            if (AnnotatedElementUtils.hasAnnotation(source, SpringBootConfiguration.class)) {
                return true;
            }
        }
        return false;
    }

    private Set<Class<?>> sources(ApplicationReadyEvent event) {
        Method method = ReflectionUtils.findMethod(SpringApplication.class, "getAllSources");
        if (method == null) {
            method = ReflectionUtils.findMethod(SpringApplication.class, "getSources");
        }
        ReflectionUtils.makeAccessible(method);
        @SuppressWarnings("unchecked")
        Set<Object> objects = (Set<Object>) ReflectionUtils.invokeMethod(method, event.getSpringApplication());
        Set<Class<?>> result = new LinkedHashSet<>();
        for (Object object : objects) {
            if (object instanceof String) {
                object = ClassUtils.resolveClassName((String) object, null);
            }
            result.add((Class<?>) object);
        }
        return result;
    }

}