Volatile Keyword Guarantees in Java

Question

In the `VolatileRecursive` class shown below, the `count` variable is declared as `volatile`. Which statement best describes the guarantees and limitations of this keyword in the context of the `recursiveIncrement` method?

```java
public class VolatileRecursive {
    private static volatile int count = 0;
    
    public static void recursiveIncrement(int n) {
        if(n <= 0) return;
        count = count + 1;
        new Thread(() -> recursiveIncrement(n - 1)).start();
    }
    
    public static void main(String[] args) throws InterruptedException {
        recursiveIncrement(5);
        Thread.sleep(1000);
        System.out.println("Count: " + count);
    }
}
```

Accepted Answer

Volatile guarantees visibility of the variable across threads but does not ensure atomicity of compound operations like incrementing.

Answer

Volatile prevents any concurrency issues by serializing access to the variable.

Answer

Volatile has no effect in a recursive method as thread communications are not involved.

Answer

Volatile guarantees both visibility and atomicity, ensuring that the count is correctly incremented.

Volatile Keyword Guarantees in Java

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