Spring集成线程池

女爷i 2023-07-01 09:59 9阅读 0赞

# 线程池ExecutorService的4种拒绝策略 #

1.  `ThreadPoolExecutor.AbortPolicy`：丢弃任务并抛出RejectedExecutionException异常
2.  `ThreadPoolExecutor.DiscardPolicy`：也是丢弃任务，但是不抛出异常。
3.  `ThreadPoolExecutor.DiscardOldestPolicy`：丢弃队列最前面的任务，执行后面的任务
4.  `ThreadPoolExecutor.CallerRunsPolicy`：由调用线程处理该任务

## 原生线程池实现 ##

// Spring原生线程池
            ThreadFactory namedThreadFactory = new ThreadFactoryBuilder()
                    .setNameFormat("demo-pool-%d").build();
            ExecutorService singleThreadPool = new ThreadPoolExecutor(1, 1,
                    0L, TimeUnit.MILLISECONDS,
                    new LinkedBlockingQueue<Runnable>(1024), namedThreadFactory, new ThreadPoolExecutor.AbortPolicy());
            singleThreadPool.execute(() -> System.out.println(Thread.currentThread().getName()));
            singleThreadPool.shutdown();

## SpringMVC集成 ##

> xml声明

## SpringBoot集成 ##

/**
     * 放一些自定义的Bean声明
     *
     * @author Created by 思伟 on 2019/12/16
     */
    @Configuration
    @EnableAsync
    public class MyBootConfig {
    
        /**
         * 线程池维护线程的最少数量
         */
        @Value("${thread-pool.core-pool-size:2}")
        private int corePoolSize;
    
        /**
         * 线程池维护线程的最大数量
         */
        @Value("${thread-pool.max-pool-size:1000}")
        private int maxPoolSize;
    
        /**
         * 线程池所使用的缓冲队列
         */
        @Value("${thread-pool.queue-capacity:200}")
        private int queueCapacity;
    
        /**
         * 线程池维护线程所允许的空闲时间
         */
        @Value("${thread-pool.keep-alive-seconds:2000}")
        private int keepAliveSeconds;
    
        /**
         * 配置线程池中的线程的名称前缀
         */
        @Value("${thread-pool.thread-name-prefix:async-resource-schedule-}")
        private String threadNamePrefix;
    
        /**
         * Spring线程池
         *
         * @return TaskExecutor
         */
        @Bean(name = AsyncExecutionAspectSupport.DEFAULT_TASK_EXECUTOR_BEAN_NAME)
        @ConditionalOnMissingBean
        public TaskExecutor taskExecutor() {
            ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
            executor.setCorePoolSize(corePoolSize);
            executor.setMaxPoolSize(maxPoolSize);
            executor.setQueueCapacity(queueCapacity);
            executor.setKeepAliveSeconds(keepAliveSeconds);
            executor.setThreadNamePrefix(threadNamePrefix);
            // rejection-policy：当pool已经达到max size的时候，如何处理新任务
            // CALLER_RUNS：不在新线程中执行任务，而是有调用者所在的线程来执行
            executor.setRejectedExecutionHandler(new ThreadPoolExecutor.AbortPolicy());
            //执行初始化
            executor.initialize();
            return executor;
        }
    }

## 如何使用 ##

/**
     * Spring线程池
     */
    @Resource
    private TaskExecutor taskExecutor;
    
    @Override
    public void run(String... args) throws Exception {
        taskExecutor.execute(() -> {
            log.info("Real thread begin to execute!");
        });
    }