Volatile Keyword and Array Thread Safety

Question

Despite using the volatile keyword for the array reference, what potential issue remains in the code?
 
```java
public class VolatileArray {
    private volatile int[] data = {0, 0, 0, 0};
    
    public void updateElement(int index, int value) {
        data[index] = value;
    }
    
    public static void main(String[] args) {
        VolatileArray va = new VolatileArray();
        Runnable r = () -> {
            for (int i = 0; i < va.data.length; i++) {
                va.updateElement(i, i + 1);
            }
        };
        Thread t1 = new Thread(r);
        Thread t2 = new Thread(r);
        t1.start();
        t2.start();
    }
}
```

Accepted Answer

The volatile keyword does not provide atomicity or visibility guarantees for individual array elements, so race conditions can still occur.

Answer

The volatile keyword prevents the array from being modified by multiple threads completely.

Answer

The volatile keyword here ensures perfect thread safety for the updateElement method and its array elements.

Answer

Using volatile on an array makes all its elements immutable, eliminating any risk of mutation.

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