问题:
ThreadLocal默认不支持子线程获取，而InheritableThreadLocal支持子线程获取threadLocal值，但是如果使用线程池，核心个数为1则子线程会获取到上一个threadLocal的值。
解决：
1.引入transmittable-thread-local jar
<dependency><groupId>com.alibaba</groupId><artifactId>transmittable-thread-local</artifactId><version>2.11.4</version>
</dependency>2. threadLocal 初始化
private static final TransmittableThreadLocal<User> CURRENT_USER_HOLDER = new TransmittableThreadLocal();
3. Executor bean,使用TtlExecutor
@Bean(value = "defaultThreadPool")public Executor buildQueueThreadPool() {ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();int cpuNum = Runtime.getRuntime().availableProcessors();// 设置核心线程数executor.setCorePoolSize(Math.min(cpuNum * 2, 16));// 设置最大线程数executor.setMaxPoolSize(cpuNum * 2);//队列中最大的数目executor.setQueueCapacity(300);//线程名称前缀executor.setThreadNamePrefix("defaultThreadPool_");//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，而是由调用者所在的线程来执行//对拒绝task的处理策略executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());//线程空闲后的最大存活时间executor.setKeepAliveSeconds(60);//加载executor.initialize();return TtlExecutors.getTtlExecutor(executor);}
