java threadlocal

The Threadlocal class in Java Multi-threading is not yet well understood, so here's a summary.The main reference is the article in http://www.cnblogs.com/dolphin0520/p/3920407.html.First, the understanding of threadlocalThreadLocal, many places are called thread-local variables, and some places are called thread-local storage, in fact, the meaning is similar. Maybe a lot of friends know that

The role of threadlocalFrom the previous analysis of threadlocal, it can be concluded thatthreadlocal is not used to solve multi-threaded access problems for shared objects by threadlocal set () The Threadlocal.threadlocalmap method is set to the thread's own object to be stored by the thread, and the other threads do not need to be accessed or accessed. The threadlocal.threadlocalmap in each thread and the

In-depth study of java.lang.ThreadLocal classI. OverviewWhat is threadlocal? In fact, Threadlocal is not a local implementation version of a thread, it is not a threaded, but a threadlocalvariable (thread local variable). Perhaps it would be more appropriate to name it Threadlocalvar. The thread local variable (ThreadLocal) function is very simple, that is, for e

threadlocal as a parameter passed in, return an ThreadLocalMap.Entry object (hereafter referred to as entry), the source code is as follows:1 private Entry Getentry (threadlocal　　Again to analyze getEntryAfterMiss(ThreadLocal, int , Entry) the source code:1// if (e = = NULL | | E.get ()! = key) 2 private Entry Getentryaftermiss (threadlocalThe above is threadlo

Usage and depth of ThreadLocal class in Java multi-thread programming, javathreadlocal usage ThreadLocal, literally translated as "Thread Local" or "local thread". If you really think so, it will be wrong! In fact, it is a container used to store local variables of the thread. I think it should be called ThreadLocalVariable (local variable of the thread). I reall

Recently look at the Android framework layer code, see threadlocal This class, a little strange, and turned over a variety of related blog one by one read; and then studied the source, and found that their understanding of the previous reading of the blog has a different point, So decided to write an article about their own understanding, hope can play the following role: Can dredge the research results, deepen their understanding Can pla

M1, it can then Lookup the value by using M1.get (this), with ' this ' as ThreadLocal and the result is ' 123″ Now-what-watch out for!Did I hear weak reference for ThreadLocal entries? Does that mean I don ' t has to clean up? Well, it's not quite. first of all, the value object is put into the ThreadLocal would not purge itself (garbage collected) if there is n

correspond to n objects, and the performance is naturally poor after a large amount of concurrency.Threadlocal has emerged in spring's transaction management, including Hibernate session management, which in web development is sometimes used to manage user session HttpSession,This typical request-first-thread scenario in web interaction seems to be more suitable for use with threadlocal, but it is important to note that because the session is associa

threadlocal when writing multithreaded code.of course, threadlocal can not replace the synchronization mechanism, the problem areas are different. The synchronization mechanism is to synchronize multiple threads for concurrent access to the same resource, which is an efficient way to communicate between multiple threads, while threadlocal is a data share that is

, rather than i++ the increment operation, otherwise it will produce dirty data, which can be avoided by using synchronized.The use of threadlocal is used to store objects for each thread. Since each thread uses its own object, there is no multithreading-related problem without competition.3.5 I have a little understanding of threadlocalOriginally, I have been thinking threadlocal design has a little bit un

the weak reference to ThreadLocal.The code (6) removes the reference to value, where the information for the current ThreadLocal object inside the front thread is cleared.Code (7) Start with the subscript of the current element to see if the other elements inside the table array have a key of NULL, and then clean up. The condition of a loop exit is that it encounters a null element in the table. So here we know that the null element behind the Entry

Java. lang. ThreadLocal 1. OverviewWhat is ThreadLocal? In fact, ThreadLocal is not a local implementation version of a Thread, it is not a thread, but Thread local variable (thread local variable ). It may be more appropriate to name it ThreadLocalVar. ThreadLocal provides

complete isolation. It can be imagined that when the object is too large, if each thread has such a "deep copy", concurrency is relatively large, the pressure on the server is naturally very large. Like the Servlet,servlet in web development is thread insecure, a request thread, multiple threads share a Servlet object, and in the early CGI design, n requests correspond to n objects, and the performance is naturally poor after a large amount of concurrency.Threadlocal has emerged in spring's tra

I. OverviewWhat is threadlocal? In fact, Threadlocal is not a local implementation version of a thread, it is not a threads, but a threadlocalvariable (thread-local variables). Perhaps it would be more appropriate to name it Threadlocalvar. Thread-local variables (ThreadLocal) are very simple in fact, is to provide a copy of the variable value for each thread tha

early CGI design, n requests correspond to n objects, and the performance is naturally poor after a large amount of concurrency.　Threadlocal has emerged in spring's transaction management, including Hibernate session management, which in web development is sometimes used to manage user session HttpSession, This typical request-first-thread scenario in web interaction seems to be more suitable for use with threadl