在使用Springboot的时候，都要涉及到服务的停止和启动，当我们停止服务的时候，很多时候大家都是kill -9 直接把程序进程杀掉，这样程序不会执行优雅的关闭。而且一些没有执行完的程序就会直接退出。

　　我们很多时候都需要安全的将服务停止，也就是把没有处理完的工作继续处理完成。比如停止一些依赖的服务，输出一些日志，发一些信号给其他的应用系统，这个在保证系统的高可用是非常有必要的。那么咱么就来看一下几种停止springboot的方法。

　　第一种就是Springboot提供的actuator的功能，它可以执行shutdown, health, info等，默认情况下，actuator的shutdown是disable的，我们需要打开它。首先引入acturator的maven依赖。

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>

　　然后将shutdown节点打开，也将/actuator/shutdown暴露web访问也设置上，除了shutdown之外还有health, info的web访问都打开的话将management.endpoints.web.exposure.include=*就可以。将如下配置设置到application.properties里边。设置一下服务的端口号为3333。

server.port=3333
management.endpoint.shutdown.enabled=true
management.endpoints.web.exposure.include=shutdown

　　接下来，咱们创建一个springboot工程，然后设置一个bean对象，配置上PreDestroy方法。这样在停止的时候会打印语句。bean的整个生命周期分为创建、初始化、销毁，当最后关闭的时候会执行销毁操作。在销毁的方法中执行一条输出日志。

package com.hqs.springboot.shutdowndemo.bean;
import javax.annotation.PreDestroy;
/**
 * @author huangqingshi
 * @Date 2019-08-17
 */
public class TerminateBean {
<span >@PreDestroy</span>
<span >public</span> <span >void</span> <span >preDestroy</span><span >()</span> <span >{</span>
    <span >System</span><span >.</span><span >out</span><span >.</span><span >println</span><span >(</span><span >"TerminalBean is destroyed"</span><span >);</span>
<span >}</span>


<span >@PreDestroy</span>
<span >public</span> <span >void</span> <span >preDestroy</span><span >()</span> <span >{</span>
    <span >System</span><span >.</span><span >out</span><span >.</span><span >println</span><span >(</span><span >"TerminalBean is destroyed"</span><span >);</span>
<span >}</span>

}

　　做一个configuration，然后提供一个获取bean的方法，这样该bean对象会被初始化。

package com.hqs.springboot.shutdowndemo.config;
import com.hqs.springboot.shutdowndemo.bean.TerminateBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
/**
 * @author huangqingshi
 * @Date 2019-08-17
 */
@Configuration
public class ShutDownConfig {
<span >@Bean</span>
<span >public</span> <span >TerminateBean</span> <span >getTerminateBean</span><span >()</span> <span >{</span>
    <span >return</span> <span >new</span> <span >TerminateBean</span><span >();</span>
<span >}</span>


<span >@Bean</span>
<span >public</span> <span >TerminateBean</span> <span >getTerminateBean</span><span >()</span> <span >{</span>
    <span >return</span> <span >new</span> <span >TerminateBean</span><span >();</span>
<span >}</span>

}

　　在启动类里边输出一个启动日志，当工程启动的时候，会看到启动的输出，接下来咱们执行停止命令。

curl -X POST http😕/localhost:3333/actuator/shutdown

　　以下日志可以输出启动时的日志打印和停止时的日志打印，同时程序已经停止。是不是比较神奇。

<img src="https://s2.51cto.com/images/blog/202305/25191943_646f444f69fbb26589.png?x-oss-process=image/watermark,size_16,text_QDUxQ1RP5Y2a5a6i,color_FFFFFF,t_30,g_se,x_10,y_10,shadow_20,type_ZmFuZ3poZW5naGVpdGk=" data-captinotallow="" data-size="normal" data-rawwidth="2436" data-rawheight="294" width="2436" data-original="https://pic4.zhimg.com/v2-48dbc39bd5395a99b51a16021bd629eb_r.jpg">

spring boot jar 停止 springboot优雅停止_spring

　　第二种方法也比较简单，获取程序启动时候的context，然后关闭主程序启动时的context。这样程序在关闭的时候也会调用PreDestroy注解。如下方法在程序启动十秒后进行关闭。

/* method 2: use ctx.close to shutdown all application context */
ConfigurableApplicationContext ctx = SpringApplication.run(ShutdowndemoApplication.class, args);
    <span >try</span> <span >{</span>
        <span >TimeUnit</span><span >.</span><span >SECONDS</span><span >.</span><span >sleep</span><span >(</span><span >10</span><span >);</span>

    <span >}</span> <span >catch</span> <span >(</span><span >InterruptedException</span> <span >e</span><span >)</span> <span >{</span>
        <span >e</span><span >.</span><span >printStackTrace</span><span >();</span>
    <span >}</span>

    <span >ctx</span><span >.</span><span >close</span><span >();</span></code></pre></div><p>　　第三种方法，在springboot启动的时候将进程号写入一个app.pid文件，生成的路径是可以指定的，可以通过命令  cat /Users/huangqingshi/app.id | xargs kill 命令直接停止服务，这个时候bean对象的PreDestroy方法也会调用的。这种方法大家使用的比较普遍。写一个start.sh用于启动springboot程序，然后写一个停止程序将服务停止。　　</p><div ><pre><code class="language-java"><span >/* method 3 : generate a pid in a specified path, while use command to shutdown pid :


    <span >try</span> <span >{</span>
        <span >TimeUnit</span><span >.</span><span >SECONDS</span><span >.</span><span >sleep</span><span >(</span><span >10</span><span >);</span>

    <span >}</span> <span >catch</span> <span >(</span><span >InterruptedException</span> <span >e</span><span >)</span> <span >{</span>
        <span >e</span><span >.</span><span >printStackTrace</span><span >();</span>
    <span >}</span>

    <span >ctx</span><span >.</span><span >close</span><span >();</span></code></pre></div><p>　　第三种方法，在springboot启动的时候将进程号写入一个app.pid文件，生成的路径是可以指定的，可以通过命令  cat /Users/huangqingshi/app.id | xargs kill 命令直接停止服务，这个时候bean对象的PreDestroy方法也会调用的。这种方法大家使用的比较普遍。写一个start.sh用于启动springboot程序，然后写一个停止程序将服务停止。　　</p><div ><pre><code class="language-java"><span >/* method 3 : generate a pid in a specified path, while use command to shutdown pid :

            'cat /Users/huangqingshi/app.pid | xargs kill' /
SpringApplication application = new SpringApplication(ShutdowndemoApplication.class);
application.addListeners(new ApplicationPidFileWriter("/Users/huangqingshi/app.pid"));
application.run();

　　第四种方法，通过调用一个SpringApplication.exit(）方法也可以退出程序，同时将生成一个退出码，这个退出码可以传递给所有的context。这个就是一个JVM的钩子，通过调用这个方法的话会把所有PreDestroy的方法执行并停止，并且传递给具体的退出码给所有Context。通过调用System.exit(exitCode)可以将这个错误码也传给JVM。程序执行完后最后会输出：Process finished with exit code 0，给JVM一个SIGNAL。

/
 method 4: exit this application using static method */
ConfigurableApplicationContext ctx = SpringApplication.run(ShutdowndemoApplication.class, args);
exitApplication(ctx);


public static void exitApplication(ConfigurableApplicationContext context) {
int exitCode = SpringApplication.exit(context, (ExitCodeGenerator) () -> 0);
    <span >System</span><span >.</span><span >exit</span><span >(</span><span >exitCode</span><span >);</span>
<span >}</span></code></pre></div><figure data-size="normal"><noscript><img src="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_b.jpg" data-caption="" data-size="normal" data-rawwidth="2434" data-rawheight="354"  width="2434" data-original="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_r.jpg"/></noscript><img src="https://pic1.zhimg.com/80/v2-a20b2b2c047067cfc73d3e9022a8fbc8_1440w.jpg" data-caption="" data-size="normal" data-rawwidth="2434" data-rawheight="354"  width="2434" data-original="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_r.jpg" data-actualsrc="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_b.jpg" data-lazy-status="ok"></figure><p>　　第五种方法，自己写一个Controller，然后将自己写好的Controller获取到程序的context，然后调用自己配置的Controller方法退出程序。通过调用自己写的/shutDownContext方法关闭程序：curl -X POST http://localhost:3333/shutDownContext。</p><div ><pre><code class="language-java"><span >package</span> <span >com.hqs.springboot.shutdowndemo.controller</span><span >;</span>

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;
/**
 * @author huangqingshi
 * @Date 2019-08-17
 */
@RestController
public class ShutDownController implements ApplicationContextAware {
<span >private</span> <span >ApplicationContext</span> <span >context</span><span >;</span>

<span >@PostMapping</span><span >(</span><span >"/shutDownContext"</span><span >)</span>
<span >public</span> <span >String</span> <span >shutDownContext</span><span >()</span> <span >{</span>
    <span >ConfigurableApplicationContext</span> <span >ctx</span> <span >=</span> <span >(</span><span >ConfigurableApplicationContext</span><span >)</span> <span >context</span><span >;</span>
    <span >ctx</span><span >.</span><span >close</span><span >();</span>
    <span >return</span> <span >"context is shutdown"</span><span >;</span>
<span >}</span>

<span >@GetMapping</span><span >(</span><span >"/"</span><span >)</span>
<span >public</span> <span >String</span> <span >getIndex</span><span >()</span> <span >{</span>
    <span >return</span> <span >"OK"</span><span >;</span>
<span >}</span>

<span >@Override</span>
<span >public</span> <span >void</span> <span >setApplicationContext</span><span >(</span><span >ApplicationContext</span> <span >applicationContext</span><span >)</span> <span >throws</span> <span >BeansException</span> <span >{</span>
    <span >context</span> <span >=</span> <span >applicationContext</span><span >;</span>
<span >}</span>


    <span >System</span><span >.</span><span >exit</span><span >(</span><span >exitCode</span><span >);</span>
<span >}</span></code></pre></div><figure data-size="normal"><noscript><img src="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_b.jpg" data-caption="" data-size="normal" data-rawwidth="2434" data-rawheight="354"  width="2434" data-original="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_r.jpg"/></noscript><img src="https://pic1.zhimg.com/80/v2-a20b2b2c047067cfc73d3e9022a8fbc8_1440w.jpg" data-caption="" data-size="normal" data-rawwidth="2434" data-rawheight="354"  width="2434" data-original="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_r.jpg" data-actualsrc="https://pic1.zhimg.com/v2-a20b2b2c047067cfc73d3e9022a8fbc8_b.jpg" data-lazy-status="ok"></figure><p>　　第五种方法，自己写一个Controller，然后将自己写好的Controller获取到程序的context，然后调用自己配置的Controller方法退出程序。通过调用自己写的/shutDownContext方法关闭程序：curl -X POST http://localhost:3333/shutDownContext。</p><div ><pre><code class="language-java"><span >package</span> <span >com.hqs.springboot.shutdowndemo.controller</span><span >;</span>

<span >private</span> <span >ApplicationContext</span> <span >context</span><span >;</span>

<span >@PostMapping</span><span >(</span><span >"/shutDownContext"</span><span >)</span>
<span >public</span> <span >String</span> <span >shutDownContext</span><span >()</span> <span >{</span>
    <span >ConfigurableApplicationContext</span> <span >ctx</span> <span >=</span> <span >(</span><span >ConfigurableApplicationContext</span><span >)</span> <span >context</span><span >;</span>
    <span >ctx</span><span >.</span><span >close</span><span >();</span>
    <span >return</span> <span >"context is shutdown"</span><span >;</span>
<span >}</span>

<span >@GetMapping</span><span >(</span><span >"/"</span><span >)</span>
<span >public</span> <span >String</span> <span >getIndex</span><span >()</span> <span >{</span>
    <span >return</span> <span >"OK"</span><span >;</span>
<span >}</span>

<span >@Override</span>
<span >public</span> <span >void</span> <span >setApplicationContext</span><span >(</span><span >ApplicationContext</span> <span >applicationContext</span><span >)</span> <span >throws</span> <span >BeansException</span> <span >{</span>
    <span >context</span> <span >=</span> <span >applicationContext</span><span >;</span>
<span >}</span>

}

好了，springboot的优雅关闭方法也都实现好了，也有同学问，如何暴力停止呢，简单，直接kill -9 相应的PID即可。

　　总结一下：

　　以上这几种方法实现的话比较简单，但是真实工作中还需要考虑的点还很多，比如需要保护暴露的点不被别人利用，一般要加一些防火墙，或者只在内网使用，保证程序安全。

　　在真实的工作中的时候第三种比较常用，程序中一般使用内存队列或线程池的时候最好要优雅的关机，将内存队列没有处理的保存起来或线程池中没处理完的程序处理完。但是因为停机的时候比较快，所以停服务的时候最好不要处理大量的数据操作，这样会影响程序停止。