Java之@Schedule與@Async注解失效問(wèn)題總結(jié)

更新時(shí)間：2026年05月09日 08:32:30 作者：想去22世紀(jì)

文章主要討論了Spring中@Scheduled和@Async注解的使用場(chǎng)景及問(wèn)題,@Scheduled方法需被Spring管理,@Async注解可能因線程池問(wèn)題導(dǎo)致異步失效,建議在測(cè)試類中使用自動(dòng)裝配確保生效

Schedule注解失效

Schedule標(biāo)記的方法的類沒有被spring托管

當(dāng)@Scheduled方法所屬的類沒有使用@Component，@Service,@Controller等修飾的時(shí)候定時(shí)任務(wù)不執(zhí)行，當(dāng)兩個(gè)定時(shí)任務(wù)同時(shí)執(zhí)行時(shí),兩個(gè)定時(shí)任務(wù)隨機(jī)先后執(zhí)行

/**
 * 當(dāng)前類不交給spring托管，定時(shí)任務(wù)失效
 * 兩個(gè)定時(shí)任務(wù)同一個(gè)時(shí)間點(diǎn)，誰(shuí)先搶到鎖誰(shuí)先執(zhí)行
 */
@Component
public class ScheduleOne {
    @Scheduled(cron = "0 22 * * * ? ")
    public void test1() {
        for (int i = 0; i < 10; i++) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("子線程名："+Thread.currentThread().getName());
            System.out.println(String.format("第%d次執(zhí)行任務(wù)一",i));
        }
    }
    @Scheduled(cron = "0 22 * * * ? ")
    public void test2() {
        for (int i = 0; i < 10; i++) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("子線程名："+Thread.currentThread().getName());
            System.out.println(String.format("第%d次執(zhí)行任務(wù)二",i));
        }
    }
}

@Async注解失效

異步任務(wù)等同于開啟了一個(gè)線程池，也可以自定義線程池

同類中調(diào)用異步方法，異步功能失效

    @Async("asyncExecutors")
    public void java() {
        System.out.println("-----------------------------------------------------elegant separator-----------------------------------------------------------------");
        for (int i = 0; i < 10; i++) {
            try {
                Thread.sleep(1000);
                System.out.println("Async++++++++子線程java名："+Thread.currentThread().getName());
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println(i + "hello java");
        }
        System.out.println("-----------------------------------------------------elegant separator-----------------------------------------------------------------");
    }

    @Test
    public void getJava() {
        java();
        System.out.println("異步任務(wù)執(zhí)行成功了嗎");
    }

執(zhí)行結(jié)果：

通過(guò)測(cè)試方法調(diào)用異步方法異步失效

    @Async
    public void python() {
        for (int i = 0; i < 10; i++) {
            try {
                Thread.sleep(1000);
                System.out.println("Async++++++++子線程java名："+Thread.currentThread().getName());
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println(i + "hello python");
        }
    }

    @Test
    public void getPython() {

        PrintOne printOne = new PrintOne();
        printOne.python();
        System.out.println("異步任務(wù)執(zhí)行成功了嗎");
    }

通過(guò)new對(duì)象調(diào)用異步方法異步失效

    @RequestMapping(method = RequestMethod.GET,value = "three")
    public String test3() {
        PrintOne printOne1 = new PrintOne();
        printOne1.python();
        System.out.println("主線程名"+ Thread.currentThread().getName());
        return "方法返回值";
    }

測(cè)試類中異步方法壓根不會(huì)進(jìn)入

@SpringBootTest
@RunWith(SpringRunner.class)
public class AsyncTest {
    /**
     * 測(cè)試類中異步方法不執(zhí)行
     */
    @Resource
    PrintOne printOne;
    @Test
    public void test1() {
        printOne.python();
        System.out.println("異步任務(wù)執(zhí)行了嗎");
    }
}

類被spring托管

且使用自動(dòng)裝配的方式調(diào)用才可以生效，且不在測(cè)試類中注解生效

    @RequestMapping(method = RequestMethod.GET,value = "one")
    public String test2() {
        printOne.java();
        System.out.println("主線程名"+ Thread.currentThread().getName());
        return "方法返回值";
    }

執(zhí)行結(jié)果

@Schedule與@Async同時(shí)存在

兩個(gè)任務(wù)可以交替執(zhí)行

@Service
public class ScheduledThree {
    @Scheduled(cron = "0 45 * * * ? ")
    @Async
    public void test1() {
        for (int i = 0; i < 20; i++) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("ScheduleThree-----子線程1名："+Thread.currentThread().getName());
        }
    }
    @Scheduled(cron = "0 45 * * * ? ")
    @Async
    public void test2() {
        for (int i = 0; i < 20; i++) {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("ScheduleThree-----子線程2名："+Thread.currentThread().getName());
        }
    }
}