Threads And Concurrency Questions
The difference between synchronized and volatile in Java is as follows:
1. Synchronized: It is a keyword used to provide mutual exclusion and thread safety in Java. When a method or block is declared as synchronized, only one thread can access it at a time. It ensures that the shared data is accessed by only one thread at a time, preventing data inconsistency and race conditions. Synchronized blocks or methods use locks to achieve synchronization.
2. Volatile: It is also a keyword used in Java to indicate that a variable's value may be modified by multiple threads. When a variable is declared as volatile, it ensures that any read or write operation on that variable is directly performed on the main memory, rather than using a thread's local cache. This guarantees that the most up-to-date value of the variable is always visible to all threads, preventing any caching-related issues.
In summary, synchronized provides mutual exclusion and thread safety by allowing only one thread to access a block or method at a time, while volatile ensures that the most recent value of a variable is always visible to all threads.