mastering concurrency programming with java 8

the fence.Ii. Publication of1 unsafe announcements In addition to immutable objects, it is generally unsafe to use objects that are initialized with one thread, unless the object's advertised operation is run before the thread that uses the object starts using it.2 Security Announcement3 Safe Initialization mode4 double check plus lockIii. security in the process of initial initializationReferences: In-depth understanding of Java memory Models"In-dep

[Java concurrent programming] 9: deadlock (including code), java concurrency A deadlock may occur when the thread needs to hold multiple locks at the same time. Consider the following situations: Thread A currently holds the lock1 lock and thread B currently holds the lock2 lock. Next, when thread A still holds lock1,

);V.stopit ();Thread.Sleep (2000);SYSTEM.OUT.PRINTLN ("Finish main");System.out.println (V.getstop ());}Iv. Rules of Happen-beforeProcedural Order Principle: the serialization of semantics within a threadVolatile rules: The write of volatile variables, which occurs first in the read, which guarantees the visibility of volatile variablesLock rule: Unlocking (unlock) must occur before the subsequent locking (lock)Transitivity: A precedes b,b before C, then a must precede CThe start () method of th

() {Clear Business Full.notifyall ();}Think of more targeted object-oriented programming. Similar issues with databases: Dirty reads: The first thing reads the data that the second thing is updating, and if the UPDATE statement is not yet complete, the first thing reads only the data in a process, not the actual result. Oracle's Things by default: Read Committed (commit read), the problem does not occurExclusive Lock: Gets an exclusive lock when the

First, the basic use of synchronizedSynchronized is one of the most common methods for solving concurrency problems in Java, and is the simplest one. There are three main functions of synchronized:(1) Ensure thread-mutually exclusive access synchronization code(2) Ensure that changes to shared variables are visible in time(3) Solve the reordering problem effectively. Syntactically speaking, there are three

"Practical Java High Concurrency Programming 1" Pointers in Java: unsafe class"Practical Java High Concurrency Programming 2" lock-free object reference: Atomicreference"Practical

resources during multithreaded access.(3) Concurrency data structureQueuedeque,List,Map,Set,(4) Executor frame setExecutor,Executorservice,Executors,Executorcompletionservice,Scheduledexecutorservice,Scheduledfuture,Scheduledthreadpoolexecutor,(5) Fork-join frame setForkjointask,Forkjoinpool,Recursivetask,Recursiveaction,Forkjoinworkerthread,(6) Atomic variable class (java.util.concurrent.atomic)Atomicboolean,Atomicinteger,Atomicintegerarray,Atomicin

Java Concurrency Programming: Concurrenthashmap of Concurrent Containers (reprint)The following part of the content is reproduced from:http://www.haogongju.net/art/2350374New concurrent packages have been added to the JDK5, and concurrent containers have improved concurrency performance through mechanisms relative to t

"Practical Java High Concurrency Programming 1" Pointers in Java: unsafe class"Practical Java High Concurrency Programming 2" lock-free object reference: AtomicreferenceAtomicreference

downgrade, follow the acquisition of write lock, read lock and then release the order of the write lock, write lock can be downgraded to read lock. Locksupport provides a park unpark static method of blocking, waking. Condition Interface : Any Java object, has a set of monitor methods, including, wait() and notify() so on, these methods and synchronized keyword Mates can implement the wait/notification mode, the Condition interface also provides

benefiting a lot, the following course system map is also available in the group. Finally, this article mainly on the Java concurrency Programming development needs of the knowledge point made a simple explanation, here every knowledge point can be explained with an article, because of space reasons can not be detailed on every knowledge point, I believe that t

Learning Java concurrency has been one months, feel some things to learn a moment will forget, do some notes but not the system, Java concurrency so Big "system", need to summarize, organize to conquer it. I hope that colleagues to learn Java concurrent

Java Concurrency Programming: Countdownlatch, Cyclicbarrier, and semaphoreIn Java 1.5, there are some very useful helper classes to help us with concurrent programming, such as Countdownlatch,cyclicbarrier and semaphore, and today we'll learn about the use of these three hel

() randomly wakes up one, Notifyall () wakes all. Wait,notify,notifyall to appear in the Synchronize synchronization block because of concurrency problems3. VolatileThe volatile keyword tells the virtual confidential key not to change the optimization target instruction arbitrarily, the order of JMM. But there is no guarantee of atomic manipulation through volatile.Third, Java and contract0. Introduction t

The Executor framework refers to a number of Executor-related functional classes in a series of concurrency libraries introduced in Java 5, including the thread pool, Executor,executors,executorservice,completionservice, Future,callable and so on. Their relationship is:A programming method for concurrent programming is

"Practical Java High Concurrency Programming 1" Pointers in Java: unsafe class"Practical Java High Concurrency Programming 2" lock-free object reference: Atomicreference"Practical

they are written. Compilers and processors may be reordered for performance optimizationsAnother function of the volatile keyword is to prevent the compiler from being optimized to prevent reordering. The following isthe V olatile, in detail on the reordering phenomenon. The characteristics of Java threading Mechanism and JMM determine the uncertainty in the process of multithreading, so it is necessary to thread synchronization to ensure thread secu

Java Concurrency Programming: Countdownlatch, Cyclicbarrier, and semaphoreIn Java 1.5, there are some very useful helper classes to help us with concurrent programming, such as Countdownlatch,cyclicbarrier and semaphore, and today we'll learn about the use of these three hel

In order to prevent unscrupulous site crawler crawling articles, hereby identified, reproduced please indicate the source of the article. Laplacedemon/shijiaqi.Http://www.cnblogs.com/shijiaqi1066/p/4852149.htmlIdentify some of the basic concepts in concurrent programmingJava concurrency (1) Multithreading basicsJava Concurrency (2) thread safety and inter-thread communicationJava

Java Concurrent Programming Series "Not finished": Java concurrency Programming: core theory Java Concurrency Programming: sync