Spring Boot 实现程序的优雅退出(详细步骤)

# 开启优雅停机，默认值：immediate 为立即关闭
server.shutdown=graceful
# 设置缓冲期，最大等待时间，默认：30秒
spring.lifecycle.timeout-per-shutdown-phase=60s

public class TomcatGracefulShutdown implements TomcatConnectorCustomizer, ApplicationListener<ContextClosedEvent> {
    private volatile Connector connector;
    public void customize(Connector connector) {
        this.connector = connector;
    }
    public void onApplicationEvent(ContextClosedEvent contextClosedEvent) {
        this.connector.pause();
        Executor executor = this.connector.getProtocolHandler().getExecutor();
        if (executor instanceof ThreadPoolExecutor) {
            try {
                log.info("Start to shutdown tomcat thread pool");
                ThreadPoolExecutor threadPoolExecutor = (ThreadPoolExecutor) executor;
                threadPoolExecutor.shutdown();
                if (!threadPoolExecutor.awaitTermination(20, TimeUnit.SECONDS)) {
                    log.warn("Tomcat thread pool did not shutdown gracefully within 20 seconds. ");
                }
            } catch (InterruptedException e) {
                log.warn("Fail to shut down tomcat thread pool ", e);
            }
        }
    }
}

@Configuration
@ConditionalOnClass({Servlet.class, Tomcat.class})
public static class TomcatConfiguration {
    @Bean
    public TomcatGracefulShutdown tomcatGracefulShutdown() {
        return new TomcatGracefulShutdown();
    }
    @Bean
    public EmbeddedServletContainerFactory tomcatEmbeddedServletContainerFactory(TomcatGracefulShutdown gracefulShutdown) {
        TomcatEmbeddedServletContainerFactory tomcatFactory = new TomcatEmbeddedServletContainerFactory();
        tomcatFactory.addConnectorCustomizers(gracefulShutdown);
        return tomcatFactory;
    }
}