This is the function of class [`InheritableThreadLocal`](https://docs.oracle.com/javase/8/docs/api/java/lang/InheritableThreadLocal.html), should use class [`InheritableThreadLocal`](https://docs.oracle.com/javase/8/docs/api/java/lang/InheritableThreadLocal.html) instead.
This is the function of class [`InheritableThreadLocal`](https://docs.oracle.com/javase/10/docs/api/java/lang/InheritableThreadLocal.html), should use class [`InheritableThreadLocal`](https://docs.oracle.com/javase/10/docs/api/java/lang/InheritableThreadLocal.html) instead.
But when use thread pool, thread is cached up and used repeatedly. Transmitting value from parent thread to child thread has no meaning.
Application need transmit value from the time task is created to the point task is executed.
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@@ -211,8 +211,8 @@ The implementation of auto adding self agent jar to `boot classpath` use the `Bo
-[Java SE 6 新特性: Instrumentation 新功能](http://www.ibm.com/developerworks/cn/java/j-lo-jse61/)
-[Creation, dynamic loading and instrumentation with javaagents](http://dhruba.name/2010/02/07/creation-dynamic-loading-and-instrumentation-with-javaagents/)
如支持配置线程池的大小（`Timer`只有一个线程）；`Timer`在`Runnable`中抛出异常会中止定时执行。更多说明参见[10. **Mandatory** Run multiple TimeTask by using ScheduledExecutorService rather than Timer because Timer will kill all running threads in case of failing to catch exceptions. - Alibaba Java Coding Guidelines](https://alibaba.github.io/Alibaba-Java-Coding-Guidelines/#concurrency)。
-[Creation, dynamic loading and instrumentation with javaagents](http://dhruba.name/2010/02/07/creation-dynamic-loading-and-instrumentation-with-javaagents/)
-[Java SE 6 新特性: Instrumentation 新功能](http://www.ibm.com/developerworks/cn/java/j-lo-jse61/)
-[Creation, dynamic loading and instrumentation with javaagents](http://dhruba.name/2010/02/07/creation-dynamic-loading-and-instrumentation-with-javaagents/)
> The Stack and the Map are managed per thread and are based on ThreadLocal by default. The Map can be configured to use an InheritableThreadLocal by setting system property isThreadContextMapInheritable to "true". When configured this way, the contents of the Map will be passed to child threads. However, as discussed in the [Executors](https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Executors.html#privilegedThreadFactory%28%29) class and in other cases where thread pooling is utilized, the ThreadContext may not always be automatically passed to worker threads. In those cases the pooling mechanism should provide a means for doing so. The getContext() and cloneStack() methods can be used to obtain copies of the Map and Stack respectively.
> The Stack and the Map are managed per thread and are based on ThreadLocal by default. The Map can be configured to use an InheritableThreadLocal by setting system property isThreadContextMapInheritable to "true". When configured this way, the contents of the Map will be passed to child threads. However, as discussed in the [Executors](https://docs.oracle.com/javase/10/docs/api/java/util/concurrent/Executors.html#privilegedThreadFactory%28%29) class and in other cases where thread pooling is utilized, the ThreadContext may not always be automatically passed to worker threads. In those cases the pooling mechanism should provide a means for doing so. The getContext() and cloneStack() methods can be used to obtain copies of the Map and Stack respectively.
