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参考链接: https://blog.csdn.net/le_17_4_6/article/details/118699111

代码案例

多线程工具类 提高执行线程和获取返回数据方法

/**
 * 多线程工具类
 */
public class ConcurrentUtil {
    /**
     * 执行任务
     *
     * @param <ResponseModel> 返回的结果集Future ResponseModel
     * @param executorService ExecutorService
     * @param callable 回调
     * @return Future ResponseModel
     */
    public static <ResponseModel> Future<ResponseModel> doJob(ExecutorService executorService, MyCallable callable) {
        return (Future<ResponseModel>) executorService.submit(callable);
    }

    /**
     * 获取结果集，执行时会阻塞直到有结果，中间的异常不会被静默
     *
     * @param future Future
     * @param <ResponseModel> 返回的结果集 ResponseModel
     * @return ResponseModel
     */
    public static <ResponseModel> ResponseModel futureGet(Future<ResponseModel> future) {
        try {
            return future.get();
        } catch (InterruptedException | ExecutionException e) {
            e.printStackTrace();
            throw new RuntimeException(e.getMessage());
        }
    }
}

公共类

/**
 * 响应结果类
 */
@Data
@ToString
public class ResponseModel implements Serializable {
    //消息
    private String message;
    //状态码
    private int messageCode;
    //结果
    private Object result;

    public ResponseModel(String message, int messageCode, Object result) {
        this.message = message;
        this.messageCode = messageCode;
        this.result = result;
    }

    public ResponseModel() {
    }
}

public final class StFlag {


    public StFlag() {
    }

    /**
     * 性别:0-男,1-女
     */
    public static final String SEX_FLAG_0 = "0";
    public static final String SEX_FLAG_1 = "1";

    /**
     * 学生服务
     */
    public static final String STUDENT_SERVICE = "STUDENT";
    /**
     * 问卷服务
     */
    public static final String QUESTION_SERVICE = "QUESTION";
}

/**
 * 多线程业务类
 */
@Slf4j
@Setter
public class MyCallable implements Serializable, Callable<ResponseModel> {
    //服务名
    private String whichServiceName;
    private StudentController studentController;
    private RequestStudentModel studentEntity;


    public MyCallable(String whichServiceName, StudentController studentController, RequestStudentModel studentEntity) {
        this.whichServiceName = whichServiceName;
        this.studentController = studentController;
        this.studentEntity = studentEntity;
    }

    @Override
    public ResponseModel call(){

        if (StFlag.STUDENT_SERVICE.equalsIgnoreCase(whichServiceName)){
            return studentController.getStudentList(studentEntity);
        }
        return studentController.getStudentList(studentEntity);
    }
}

/**
 * 学生相关控制器,真正业务类,具体业务了逻辑自己实现
 */
@RestController
@RequestMapping("/student")
@Slf4j
public class StudentController {

    @Autowired
    private StudentService studentService;

    /**
     * 查询问卷校验项
     * @return
     */
    @PostMapping("/getStudentList")
    public ResponseModel getStudentList(@RequestBody RequestStudentModel studentEntity){
        try {
            Thread.sleep(2000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return new ResponseModel("查询成功", 200, "");
    }
}

测试主类

特别注意, ConcurrentUtil.futureGet(responseRqestionFuture);方法要在所有线程执行完之后执行,否则达不到多线程执行的效果,因为future.get()会阻塞,知道拿到返回值

/**
 * 多线程控制器
 */
@RestController
@RequestMapping("/concurrent")
@Slf4j
public class CurrentController {
    @Autowired
    private StudentController studentController;
    /**
     * 多线程测试
     * @return
     */
    @PostMapping("/current")
    public ResponseModel getStudentList(@RequestBody RequestStudentModel studentEntity) throws ExecutionException, InterruptedException {
        log.info("current   ---- start ");
        List list = new ArrayList();
        ExecutorService executorService = new ThreadPoolExecutor(2, 2, 3,
                TimeUnit.SECONDS, new LinkedBlockingQueue<>(30), Executors.defaultThreadFactory(),
                new ThreadPoolExecutor.CallerRunsPolicy());
//        另一种方式创建线程池,不推荐,因为不能修改内部参数,比如队列类型
//        ExecutorService executorService = Executors.newFixedThreadPool(20);
//        多线程调用方式
//        MyCallable myCallable= new MyCallable(StFlag.STUDENT_SERVICE,studentController, studentEntity);
//        Future<ResponseModel> submit = executorService.submit(myCallable);
//        ResponseModel responseModel1 = submit.get();
        long timeStart = System.currentTimeMillis();
        // 查询问卷
        Future<ResponseModel> responseRqestionFuture = ConcurrentUtil.doJob(executorService,
                new MyCallable(StFlag.STUDENT_SERVICE,studentController, studentEntity));
        // 查询学生
        Future<ResponseModel> responseSudentFuture = ConcurrentUtil.doJob(executorService,
                new MyCallable(StFlag.QUESTION_SERVICE,studentController, studentEntity));
        //future.get方法
        //线程池线程是异步提交的，但是返回分页结果是需要同步返回，Future的get是个阻塞方法。
        // 只有所有的任务全部完成，我们才能用get按照任务的提交顺序依次返回结果，
        // 调用future.get()方法查看线程池内所有方法是否已执行完成，达到线程异步提交，结果集同步返回的效果。
        ResponseModel myCallableResponseModel1 = ConcurrentUtil.futureGet(responseRqestionFuture);
        ResponseModel myCallableResponseModel2 = ConcurrentUtil.futureGet(responseSudentFuture);
        long timeMiddle = System.currentTimeMillis();
        long longMutiThread = timeMiddle - timeStart;
        log.info("多线程执行用时为: {}", longMutiThread);
        list.add("多线程执行用时为: "+longMutiThread);
        // 单线程查询
        ResponseModel responseModel = studentController.getStudentList(studentEntity);
        ResponseModel studentList = studentController.getStudentList(studentEntity);
        long timeEnd = System.currentTimeMillis();
        long longDingleThread = timeEnd - timeMiddle;
        log.info("单线程执行用时为: {}", longDingleThread);
        list.add("单线程执行用时为: "+longDingleThread);
        list.add(myCallableResponseModel1);
        list.add(myCallableResponseModel2);
        list.add(responseModel);
        list.add(studentList);
        log.info("current   ---- end ");

        return new ResponseModel("多线程测试完成", 200, list);
    }
}

测试案例

POSTMan测试

控制台打印

2022-07-02 01:48:37.521 INFO  current   ---- start  【http-nio-8081-exec-2】【CurrentController:34】
2022-07-02 01:48:39.552 INFO  多线程执行用时为: 2144 【http-nio-8081-exec-2】【CurrentController:60】
2022-07-02 01:48:43.588 INFO  单线程执行用时为: 4028 【http-nio-8081-exec-2】【CurrentController:67】
2022-07-02 01:48:43.589 INFO  current   ---- end  【http-nio-8081-exec-2】【CurrentController:73】

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