AtomicReferenceArray weakCompareAndSetPlain() method in Java with Examples

The weakCompareAndSetPlain() method of a AtomicReferenceArray class is used to atomically sets the value of the element at index i to newValue to newValue for AtomicReferenceArray if the current value is equal to expectedValue passed as parameter. This method updates the value at index i with memory semantics of setting as if the variable at index i was declared non-volatile and non-final.This method returns true if set a new value is successful.

Syntax:

public final boolean weakCompareAndSetPlain(int i,
                                            E expectedValue,
                                            E newValue)

Parameters: This method accepts i which is an index of AtomicReferenceArray to perform the operation, expectedValue which is the expected value and newValue which is the new value to set.

Return value: This method returns true if successful.

Below programs illustrate the weakCompareAndSetPlain() method:
Program 1:

// Java program to demonstrate AtomicReferenceArray
// weakCompareAndSetPlain() method

import java.util.concurrent.atomic.AtomicReferenceArray;

public class GFG {

    public static void main(String[] args)
    {

        // create an atomic reference object.
        AtomicReferenceArray<Integer> ref
            = new AtomicReferenceArray<Integer>(5);

        // set some value
        ref.set(0, 321);
        ref.set(1, 123);
        ref.set(2, 322);

        // apply weakCompareAndSetPlain()
        boolean result
            = ref.weakCompareAndSetPlain(
                0, 124,
                234);

        // print value
        System.out.println("Setting new value"
                           + " is successful = "
                           + result);

        System.out.println("Value of index 0 = "
                           + ref.get(1));
    }
}

Output:

Program 2:

// Java program to demonstrate AtomicReferenceArray
// weakCompareAndSetPlain() method

import java.util.concurrent.atomic.AtomicReferenceArray;

public class GFG {

    public static void main(String[] args)
    {

        // create an atomic reference object.c
        AtomicReferenceArray<String> ref
            = new AtomicReferenceArray<String>(5);

        // set some value
        ref.set(0, "C");
        ref.set(1, "JAVA");
        ref.set(2, "JS");
        ref.set(3, "C++");
        ref.set(4, "C");

        // apply weakCompareAndSetVolatile()
        boolean result
            = ref.weakCompareAndSetVolatile(
                4, "C",
                "PYTHON");

        // print value
        System.out.println("Setting new value"
                           + " is successful = "
                           + result);

        System.out.println("Value of index 4 = "
                           + ref.get(4));
    }
}

Output:

References: https://docs.oracle.com/javase/10/docs/api/java/util/concurrent/atomic/AtomicReferenceArray.html#weakCompareAndSetPlain(V, V)