Spring Boot 应用优雅关闭详解

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
import org.springframework.context.annotation.Bean;
import org.springframework.scheduling.annotation.EnableScheduling;
 
@SpringBootApplication
@EnableScheduling
@EnableConfigurationProperties(WebMvcProperties.class)
public class Application extends SpringBootServletInitializer {
 
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }
 
    public static void main(String[] args) throws Exception {
        SpringApplication.run(Application.class, args);
    }
 
    @Bean
    public GracefulShutdown gracefulShutdown() {
        return new GracefulShutdown();
    }
}
 
class GracefulShutdown {
 
    private static final Logger LOGGER = LoggerFactory.getLogger(GracefulShutdown.class);
 
    private final ExecutorService executorService;
 
    public GracefulShutdown() {
        this.executorService = Executors.newSingleThreadExecutor();
    }
 
    public void shutdown() {
        LOGGER.info("开始优雅关闭...");
        executorService.shutdown();
        try {
            if (!executorService.awaitTermination(10, TimeUnit.SECONDS)) {
                executorService.shutdownNow();
                if (!executorService.awaitTermination(10, TimeUnit.SECONDS)) {
                    LOGGER.error("优雅关闭任务未能正常结束，强制终止");
                }
            }
        } catch (InterruptedException ie) {
            executorService.shutdownNow();
            Thread.currentThread().interrupt();
        }
        LOGGER.info("优雅关闭完成");
    }
}

这个代码示例展示了如何在Spring Boot应用中实现优雅关闭。它定义了一个名为GracefulShutdown的类，其中包含了关闭逻辑。在应用程序关闭时，它会尝试优雅地关闭一个单线程的ExecutorService。如果在指定时间内线程池没有正常关闭，它会尝试强制关闭所有执行中的任务。这个例子对于需要优雅处理关闭请求的场景，如Web服务、后台任务调度等，提供了一个很好的实践。