Java線程的幾種狀態(tài)

1、123456789101112131415161718192021222324252627中定義的集中Java線程的狀態(tài)：/*A thread state. A thread can be in one of the following states:link #NEWA thread that has not yet started is in this state. TOC o 1-5 h z link ttRUNNABLEA thread executing in the Java virtual machine is in this state.link ttBLOCKED)A thr

2、ead that is blocked waiting for a monitor lockis in this state.link ttWAITINGA thread that is waiting indefinitely for another thread toperform a particular action is in this state.link #TIMED_WAITINGA thread that is waiting for another thread to perform an actionfor up to a specified waiting time i

3、s in this state.link ttTERMINATEDA thread that has exited is in this state.*28 * A thread can be in only one state at a given point in time.* These states are virtual machine states which do not reflect* any operating system thread states.* since 1. 5* see ttgetState*/public enum State TOC o 1-5 h z

4、 /*沒有start。的線程狀態(tài)*/NEW,/*可運(yùn)行線程的線程狀態(tài)。處于可運(yùn)行狀態(tài)的線程正在Java虛擬機(jī)中執(zhí)行，但它可能正在等待來自操作系統(tǒng)(如處理器)的其他資源*/RUNNABLE,/*線程處于阻塞狀態(tài)。在進(jìn)入或者重新進(jìn)入synchronized代碼塊/方法時(shí)，等待monitor lock的一種狀態(tài)*/BLOCKED,/*線程處于等待狀態(tài)。，由于調(diào)用以下方法之一，線程會(huì)處于等待狀態(tài)：*Object, wait ()沒有超時(shí)時(shí)間*Thread. join()沒有超時(shí)時(shí)間*LockSupport. park()*/WAITING,/*具有指定等待時(shí)間的等待狀態(tài)。調(diào)用以下方法之一，在指定的等待

5、時(shí)間內(nèi)，使線程處于等待狀態(tài)：*Thread, sleep*Objectftwait (long)有超時(shí)時(shí)間*Thread, join (long) 有超時(shí)時(shí)間*LockSupport. parkNanos*LockSupport. parkCntil TOC o 1-5 h z */TIMED_WAITING,68/*終止?fàn)顟B(tài)。線程已完成執(zhí)行*/TERMINATED;mterruptO上述Java代碼定義的幾個(gè)狀態(tài)中其實(shí)是沒有running狀態(tài)的。線程的runnable狀態(tài)是從虛擬機(jī)的角度來看的，表示這個(gè)線程正在運(yùn)行。但是 處于Runnable狀態(tài)的線程不一定真地消耗CPU.處于Runnabl

6、e的線程只能 說明該線程沒有阻塞在java的wait或者sleep方法上，同時(shí)也沒等待在鎖上 面。但是如果該線程調(diào)用了本地方法，而本地方法處于等待狀態(tài)，這個(gè)時(shí)候 虛擬機(jī)是不知道本地代碼中發(fā)生了什么，此時(shí)盡管當(dāng)前線程實(shí)際上也是阻塞的 狀態(tài)，但實(shí)際上顯示出來的還是runnable狀態(tài)，這種情況下是不消耗CPU 的。阻塞與等待的區(qū)別：阻塞：當(dāng)一個(gè)線程試圖獲取對象鎖(非庫中的鎖，即 synchronized ),而該鎖被其他線程持有，那么該線程進(jìn)入阻塞狀態(tài)。它的特點(diǎn) 是使用簡單，由JVM調(diào)度器來決定喚醒自己，而不需要由另一個(gè)線程來顯式喚 醒自己，不響應(yīng)中斷。等待：當(dāng)一個(gè)線程等待另一個(gè)線程通知調(diào)度器一個(gè)條件時(shí)，該線程進(jìn)入等