java concurrency in practice

Reprint Please specify source:http://blog.csdn.net/ns_code/article/details/17511147Blocking QueuesThe blocking queue is the content in the new Java 5 concurrency feature, and the interface for the blocking queue is Java.util.concurrent.BlockingQueue, which has multiple implementation classes: Arrayblockingqueue, Delayqueue, Linkedblockingqueue, Priorityblockingqueue, Synchronousqueue, etc., the use of a sim

Concurrency overview>> SyncHow to synchronize access to shared resources by multiple threads is one of the most basic problems in multithreaded programming.When multiple threads access shared data concurrently, the data is in an intermediate or inconsistent state, which affects the correct operation of the program. We often call this a race condition (race condition), which is called a critical area (critical section) for concurrent access to shared d

; }} enq (node);return node; Where the queue operation is as follows/*** Inserts node into queue, initializing if necessary. See picture above.* @param node The node to insert * @return node ' s predecessor*/private node Enq (Final node node) { For (;;) {Node T =tail; if (t = = null) { //must initialize if (Compareandsethead (new Node ())) tail = head; }else {Node.prev = t; if (compareandsettail (t, node)) { T.next = node; return T; }}}} Abstractqueuedsynchronizer has two main methods: the A

1. Longadder and Atomiclong similar use, but the performance is better than Atomiclong. Both Longadder and Atomiclong use atomic operations to improve performance. But longadder on the basis of Atomiclong, hot spot separation is similar to the reduction of lock granularity in the lock operation, and a lock is separated into several locks to improve performance. In the absence of locks, a similar approach can be used to increase the success rate of CAS, thereby improving performance. Longadder

1th Course Introduction (Java Concurrent Programming Advanced course)What is Disruptor? It is a high-performance asynchronous processing framework, known as the "single-threaded processing of 600W orders per second" artifact, the goal of this course: a thorough mastery of such an excellent open source framework, interview seconds to kill the interviewer. This chapter will lead the small partners to understand the syllabus and focus, and then simulate

19) Java concurrency, 19java concurrency > Synchronized Synchronized keyword, It includes two usage methods: synchronized Method and synchronized Block. 1> synchronized Method: Declare the synchronized Method by adding the synchronized keyword to the method declaration. Public synchronized void accessVal (int newVal ); The synchronized method controls access

Multithreaded programming also brings some security issues while improving program performance, producing unpredictable results. The reason for this is that the sequence of operations in each thread in multiple threads is unpredictable, and the resource operations shared by each thread are likely to interact with each other. For example, statistics on the number of accesses to a page, the value of an int type is accumulated, each thread accepts the user request will be added to the int type. The

threads are created in the code above, there can be only one thread executing concurrently. The semaphore method Semaphore (int permits) accepts an integer number that represents the number of licenses available. Semaphore (10) indicates that 10 threads are allowed to obtain a license, that is, the maximum number of concurrent is 10. Semaphore is also very simple to use, first the thread uses the semaphore acquire () method to obtain a license, and then call the release () method to return the

Java beginner course video practice-Beginner online, quiz game, ATM practice, welcome to watch, atm practice Java introductory course video practice-elementary The upload is complete. Welcome to the audience Go directly: Htt

Unit,BlockingqueueThreadfactory Threadfactory,Rejectedexecutionhandler handler)For the thread pool, if there is always a backlog of tasks, you can increase the corepoolsize size appropriately, and if the machine load is low, you can increase the maximumpoolsize size appropriately. , reducing the KeepAliveTime time in a task queue can help reduce the load, and the length of the task queue and the task queue's deny policy also have some impact on the processing of the task.In layman's

[JAVA concurrent programming practice] 10. concurrent program testing and java practice1. Generate a random number Package cn. study. concurrency. ch12; public class Util {public static int xorShift (int y) {// shift left and unsigned right, and last XOR operation (XOR, if the two bits are different, the value is 1; o

[JAVA concurrent programming practice] 8. Lock sequence deadlock and java practice Package cn. study. concurrency. ch10; public class Account {private String staffAccount; // Account private String passWord; // passWord private int balance; // Account balance public Account

[JAVA concurrent programming practice] 9. Lock segmentation and java practice Package cn. study. concurrency. ch11;/*** lock segmentation * @ author xiaof **/public class StripedMap {// synchronization policy: locks the array in segments, n nodes use the n % LOCKS lock to pr

write operation is volatile also called a variable rule before the next read Operation volatile . Any operation within a thread must be called after the start () Call of this thread, also known as the thread initiation rule. A thread terminates the rule before all operations on a thread are terminated. The end operation of an object must also be called an object finalization rule after the object is constructed. Transitivity I strongly recommend that you read the 16th chapt

Java course practice log (Thursday) and java practice log Import java. awt. eventQueue; import javax. imageio. imageIO; import javax. swing. JFrame; import javax. swing. JPanel; import javax. swing. border. emptyBorder; import javax. swing. abstractButton; import javax. swin

Java concurrent programming and java concurrency This article records the immutability of the policy to ensure concurrency security. (Note: It is Immutable, not Invariant !) Organizes a series of actions into an atomic operation to ensure immutability conditions, or uses a synchronization mechanism to ensure visibilit

execute read operations and write operations can also concurrently access map, and allow a certain number of write operation threads to modify map concurrently, therefore, it can achieve higher throughput in a concurrent environment. In addition, concurrent containers provide some composite operations that need to be implemented by themselves when using synchronous containers, including putIfAbsent, but because concurrent containers cannot exclusively access through locking, we cannot implement

[JAVA concurrent programming practice] 3. Synchronization container and java practice The synchronization containers include Vector and Hashtable, and some are created by factory methods such as Collections. synchronizedXxx. 1. Synchronization container Problems Synchronization containers are thread-safe, but sometim

Java concurrent programming and java concurrency The reason why Latch and Barrier are put together is that they give people a similar feeling.They all block some behaviors until an event occurs, but Latch is waiting for an event, while Barrier is waiting for the thread. First, compare the descriptions of the two in JCIP:Latch-A latch is a synchronizer that can de

[JAVA concurrent programming practice] 11. Implementation of bounded cache and java practice1. bounded cache base class Package cn. xf. cp. ch14;/*** function: bounded cache implementation base class * Time: 2:20:00 * file: BaseBoundedBuffer. java * @ author Administrator ** @ param 2. Determine the prerequisites befo