Java CAS Learning

CAS (Compare and Swap), a technique that is often used to implement concurrency algorithms by comparing and replacing

CAS (V,A,B)

The idea of CAS is simple: three parameters, a current memory value of V, an old expected value of a, an updated value of B, when and only if the expected value A and the memory value of the V phase, the memory value is modified to B and return true, otherwise do nothing and return false

Because the CAS operation is optimistic, it always thinks that it can successfully complete the operation, when multiple threads use CAs to manipulate a variable, only one wins, and the other succeeds, and the rest fails, but the failed thread is not suspended, only to be told that it failed, and to allow another attempt, Of course, the failed thread is allowed to abort the operation

Java CAS Learning