5/11/2023 0 Comments Java file synchronization![]() In Java, wait(), notify() and notifyAll() are the important methods that are used in synchronization.For example, If in synchronized(instance), instance is null then it will throw null pointer exception. Java synchronization will throw null pointer exception if Object used in synchronized block is null.When thread enters into synchronized instance method or block, it acquires Object level lock and when it enters into synchronized static method or block it acquires class level lock.When a thread enters into synchronized method or block, it acquires lock and once it completes its task and exits from the synchronized method, it releases the lock.If one thread is executing the synchronized method, all others thread that invoke synchronized method on the same Object will have to wait until first thread is done with the Object.Įxample: This shows if more than one threads accessing getLine() method without synchronization. It is not possible for two invocations for synchronized methods to interleave. ![]() If a Object is visible to more than one threads, all reads or writes to that Object’s fields are done through the synchronized method. Synchronized methods enables a simple strategy for preventing the thread interference and memory consistency errors. Statement(s) synchronization (Block synchronization).Java programming language provide two synchronization idioms: If shared Object is immutable or all the threads which share the same Object are only reading the Object’s state not modifying then you don’t need to synchronize it. Synchronization is needed when Object is mutable. If an Object is shared by multiple threads then there is need of synchronization in order to avoid the Object’s state to be getting corrupted. We need to synchronize the shared resources to ensure that at a time only one thread is able to access the shared resource. Java is multi-threaded language where multiple threads runs parallel to complete their execution. That’s why we need to synchronize the access to shared variable i. But it should be 2 by the effect of both threads. Now 2nd thread accesses the value of i that would be 0 as 1st thread did not store it back to its location.Īnd 2nd thread also increment it and store it back to its location.(Currently value i is 0) and increases it by one, so value of variable i becomes 1. And store the increased value of i to its location.In above example three operations are performed: ISRO CS Syllabus for Scientist/Engineer Exam.ISRO CS Original Papers and Official Keys.GATE CS Original Papers and Official Keys.
0 Comments
Leave a Reply. |