ctice
五、使用 BufferedWriter 进行缓冲
这里不给大家举例,可自行尝试。
六、Deferred 方式实现异步调用
代码如下:
@RestController
public class AsyncDeferredController {
private final Logger logger = LoggerFactory.getLogger(this.getClass());
private final LongTimeTask taskService;
@Autowired
public AsyncDeferredController(LongTimeTask taskService) {
this.taskService = taskService;
}
@GetMapping("/deferred")
public DeferredResult<String> executeSlowTask() {
logger.info(Thread.currentThread().getName() + "进入executeSlowTask方法");
DeferredResult<String> deferredResult = new DeferredResult<>();
// 调用长时间执行任务
taskService.execute(deferredResult);
// 当长时间任务中使用deferred.setResult("world");这个方法时,会从长时间任务中返回,继续controller里面的流程
logger.info(Thread.currentThread().getName() + "从executeSlowTask方法返回");
// 超时的回调方法
deferredResult.onTimeout(new Runnable(){
@Override
public void run() {
logger.info(Thread.currentThread().getName() + " onTimeout");
// 返回超时信息
deferredResult.setErrorResult("time out!");
}
});
// 处理完成的回调方法,无论是超时还是处理成功,都会进入这个回调方法
deferredResult.onCompletion(new Runnable(){
@Override
public void run() {
logger.info(Thread.currentThread().getName() + " onCompletion");
}
});
return deferredResult;
}
}
七、异步调用可以使用 AsyncHandlerInterceptor 进行拦截
代码如下:
@Component
public class MyAsyncHandlerInterceptor implements AsyncHandlerInterceptor {
private static final Logger logger = LoggerFactory.getLogger(MyAsyncHandlerInterceptor.class);
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
// HandlerMethod handlerMethod = (HandlerMethod) handler;
logger.info(Thread.currentThread().getName()+ "服务调用完成,返回结果给客户端");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
throws Exception {
if(null != ex){
System.out.println("发生异常:"+ex.getMessage());
}
}
@Override
public void afterConcurrentHandlingStarted(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
// 拦截之后,重新写回数据,将原来的hello world换成如下字符串
String resp = "my name is chhliu!";
response.setContentLength(resp.length());
response.getOutputStream().write(resp.getBytes());
logger.info(Thread.currentThread().getName() + " 进入afterConcurrentHandlingStarted方法");
}
}
参考资料:
版权声明:本文为CSDN博主「灬点点」的原创文章,遵循CC 4.0 BY-SA版权协议,转载请附上原文出处链接及本声明。原文链接:https://blog.csdn.net/qq_32447301/article/details/88046026
近期热文推荐:
1.1,000+ 道 Java面试题及答案整理(2022最新版)
2.劲爆!Java 协程要来了。。。
3.Spring Boot 2.x 教程,太全了!
4.别再写满屏的爆爆爆炸类了,试试装饰器模式,这才是优雅的方式!!
5.《Java开发手册(嵩山版)》最新发布,速速下载!
觉得不错,别忘了随手点赞+转发哦!