Springboot的異步線程池圖鑒
阿新 • • 發佈:2019-02-11
ask 設置 tar line exe dot conf setw close
1:定義線程池
@EnableAsync @Configuration class TaskPoolConfig { @Bean("taskExecutor") public Executor taskExecutor() { ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor(); executor.setCorePoolSize(10); executor.setMaxPoolSize(View Code20); executor.setQueueCapacity(200); executor.setKeepAliveSeconds(60); executor.setThreadNamePrefix("taskExecutor-"); executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy()); executor.setWaitForTasksToCompleteOnShutdown(true); executor.setAwaitTerminationSeconds(60); return executor; } }
2:如何使用該線程池呢?
@Slf4j @Component public class Task { public static Random random = new Random(); @Autowired private StringRedisTemplate stringRedisTemplate; @Async("taskExecutor") public void doTaskOne() throws Exception { log.info(View Code"開始做任務一"); long start = System.currentTimeMillis(); Thread.sleep(random.nextInt(10000)); long end = System.currentTimeMillis(); log.info(stringRedisTemplate.randomKey()); log.info("完成任務一,耗時:" + (end - start) + "毫秒"); } @Async("taskExecutor") public void doTaskTwo() throws Exception { log.info("開始做任務二"); long start = System.currentTimeMillis(); Thread.sleep(random.nextInt(10000)); long end = System.currentTimeMillis(); log.info("完成任務二,耗時:" + (end - start) + "毫秒"); } @Async("taskExecutor") public void doTaskThree() throws Exception { log.info("開始做任務三"); long start = System.currentTimeMillis(); Thread.sleep(random.nextInt(10000)); long end = System.currentTimeMillis(); log.info("完成任務三,耗時:" + (end - start) + "毫秒"); } }
3 執行異步任務
@RunWith(SpringJUnit4ClassRunner.class) @SpringBootTest public class ApplicationTests { @Autowired private Task task; @Test public void test() throws Exception { task.doTaskOne(); task.doTaskTwo(); task.doTaskThree(); Thread.currentThread().join(); } }View Code
4 打印結果
2018-03-27 22:01:15.620 INFO 73703 --- [ taskExecutor-1] com.didispace.async.Task : 開始做任務一 2018-03-27 22:01:15.620 INFO 73703 --- [ taskExecutor-2] com.didispace.async.Task : 開始做任務二 2018-03-27 22:01:15.620 INFO 73703 --- [ taskExecutor-3] com.didispace.async.Task : 開始做任務三 2018-03-27 22:01:18.165 INFO 73703 --- [ taskExecutor-2] com.didispace.async.Task : 完成任務二,耗時:2545毫秒 2018-03-27 22:01:22.149 INFO 73703 --- [ taskExecutor-3] com.didispace.async.Task : 完成任務三,耗時:6529毫秒 2018-03-27 22:01:23.912 INFO 73703 --- [ taskExecutor-1] com.didispace.async.Task : 完成任務一,耗時:8292毫秒View Code
5 註意事項
註: @Async所修飾的函數不要定義為static類型,這樣異步調用不會生效
從異常信息JedisConnectionException: Could not get a resource from the pool
來看,我們很容易的可以想到,在應用關閉的時候異步任務還在執行,由於Redis連接池先銷毀了,導致異步任務中要訪問Redis的操作就報了上面的錯。所以,我們得出結論,上面的實現方式在應用關閉的時候是不優雅的,那麽我們要怎麽做呢?如下設置:
executor.setWaitForTasksToCompleteOnShutdown(
true
);
executor.setAwaitTerminationSeconds(
60
);
Springboot的異步線程池圖鑒