Programmer Think

Concurrent programming synchronized What I said earlier As I said at the beginning, I want to sort out some learning documents of java Concurrent Programming. This is the third article: synchronized keyword. It mainly discusses the use of synchronized keywords, lock principle, lock reentry, dirty reading, lock upgrade and other issues. Welc ...

preface 1, synchronized and Volatile volatile Visibility can be guaranteed, but atomicity cannot be guaranteed (thread safety problem) Prohibit reordering synchronized Both visibility and atomicity can be guaranteed Reordering is not prohibited synchronized is blocking. Only one thread can access it at a time 2, Reorder Concept: the c ...

catalogue Title: answer: Explanation: Recently, I did a topic of multithreading synchronization. I used conditional locking to solve it. By doing this problem, we can have a basic understanding of the application of locks. This article will briefly explain it. Ps: after finishing, I found that this is the original question on Li buckle. T ...

JDK1. 8 source code analysis of concurrenthashmap jdk1.8 container initialization Source code analysis There are five construction methods in the ConcurrentHashMap of jdk8. None of the four construction methods initialize the internal array, but deal with the initial values of some variablesThe array initialization of concurrent HashMap of j ...

This paper first introduces the concept of optimistic lock, then introduces the implementation principle of optimistic lock, and finally demonstrates the implementation of optimistic lock with a spring boot project. catalogue What is optimistic lock Implementation principle of optimistic lock actual combat What is optimistic lock Durin ...

In the concurrent environment, in order to ensure the thread safety of sharing variable data, we need to use the locking mechanism. If the lock is not used properly, it may cause deadlock, thread starvation and other problems. If a deadlock occurs in a Java application, the program cannot be recovered automatically, which will seriously cause ...

Introduction and optimization process of simple second kill system windows native hardware configuration: 8-core 32G linux server hardware configuration: 2-core 4G Foreword, the optimized simple second kill system does not involve distribution, so naturally there are no technical points such as master-slave replication. Here, we should a ...

1. Introduction to Exchanger Exchanger - Exchanger, JDK1. A synchronizer was introduced at 5th hour, and it can be seen literally that the main function of this class is to exchange data. Exchanger is a bit like CyclicBarrier, we know that CyclicBarrier is a fence, and threads that reach it need to wait for a certain number of other threads t ...

Detailed explanation of the underlying principle and source code analysis of java Concurrent thread pool Performance comparison between thread and thread pool The first part analyzes Java threads. Now let's analyze the java thread pool. Before analyzing the thread pool, let's think about whether the more threads we create, the better. Obv ...

Basic use of synchronized Object lock Custom object lock /** * Object lock example 2 */ public class SyncObjLock2 implements Runnable{ private static SyncObjLock2 instance=new SyncObjLock2(); private Object lock1=new Object(); private Object lock2=new Object(); /** * You can see that using sync will cause threads to ...