Thread.join()

將線程A加入到當(dāng)前執(zhí)行線程中，只有當(dāng)線程A執(zhí)行完畢，當(dāng)前線程才能繼續(xù)執(zhí)行；

join方法是同步的，使用synchronized關(guān)鍵字，底層調(diào)用wait方法；

例：

主線程在執(zhí)行過(guò)程中，調(diào)用線程對(duì)象threadA.join()方法，獲得了threadA對(duì)象的鎖，同時(shí)在join方法內(nèi)部調(diào)用threadA的wait方法阻塞當(dāng)前主線程；

Thread.ThreadLocal

InheritableThreadLocal，共享父類的ThreadLocal內(nèi)容；

https://zhuanlan.zhihu.com/p/28501035

Thread.interrupt()

如果當(dāng)前線程處于運(yùn)行狀態(tài)，調(diào)用interrupt()只是設(shè)置當(dāng)前線程的中斷標(biāo)記位，不會(huì)中斷當(dāng)前線程的運(yùn)行；

如果當(dāng)前線程調(diào)用了wait或sleep方法，當(dāng)前線程處于阻塞狀態(tài)，則線程清空中斷標(biāo)記位，并拋出InterruptedException異常；
Thread.interrupted()，判斷當(dāng)前線程是否處于中斷狀態(tài)，如果是，返回true，同時(shí)清空中斷標(biāo)記位；即該方法第二次調(diào)用時(shí)將返回false；

Thread State

BLOCKED，線程阻塞在獲取鎖的時(shí)候

WAITING，線程調(diào)用了wait、join或LockSupport.park方法

Thread.stop() @Deprecated

調(diào)用stop方法，會(huì)釋放線程持有的所有鎖，此時(shí)原來(lái)被鎖保護(hù)的對(duì)象可能處于中間態(tài)。如果其他線程獲取了鎖，并對(duì)該中間態(tài)的對(duì)象進(jìn)行操作，結(jié)果無(wú)法確定；以下是官方注解。

Stopping a thread with * Thread.stop causes it to unlock all of the monitors that it * has locked (as a natural consequence of the unchecked * <code>ThreadDeath</code> exception propagating up the stack). If * any of the objects previously protected by these monitors were in * an inconsistent state, the damaged objects become visible to * other threads, potentially resulting in arbitrary behavior. Many * uses of <code>stop</code> should be replaced by code that simply * modifies some variable to indicate that the target thread should * stop running. The target thread should check this variable * regularly, and return from its run method in an orderly fashion * if the variable indicates that it is to stop running. If the * target thread waits for long periods (on a condition variable, * for example), the <code>interrupt</code> method should be used to * interrupt the wait.