volatile

Example

Declare a volatile attribute.

public class Main {
  public static volatile int x = 5;

 
  public static void main(String[] args) {
    System.out.println(x);
  }
}

Definition and Usage

The volatile keyword is a modifier that ensures an attribute’s value is consistently read the same across all threads.

Ordinarily, an attribute’s value may be written to a thread’s local cache and not immediately updated in main memory, causing other threads to see a different value. The volatile keyword ensures that threads always update and read the attribute’s value directly from main memory.