The Java.util.concurrent.atomic.AtomicLongArray.accumulateAndGet() is an inbuilt method in java that atomically updates the element at index i with the results of applying the given function to the current and given values, returning the updated value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value at index i as its first argument, and the given update as the second argument.
Syntax:
public final long accumulateAndGet(int i, long x, LongBinaryOperator accumulatorFunction)
Parameters: The function accepts three parameters:
Return value: The function returns the updated value which is in long.
Below programs illustrate the above method:
Program 1:
// Java program that demonstrates// the accumulateAndGet() function import java.util.concurrent.atomic.AtomicLongArray;import java.util.function.LongBinaryOperator; public class GFG { public static void main(String args[]) { // Initializing an array long a[] = { 1, 2, 3, 4, 5 }; // Initializing an AtomicLongArray with array a AtomicLongArray arr = new AtomicLongArray(a); // Displaying the AtomicLongArray System.out.println("The array : " + arr); // Index where update is to be made int idx = 4; // Value to make operation with value at idx long x = 5; // Declaring the accumulatorFunction LongBinaryOperator add = (u, v) -> u + v; // Updating the value at idx // applying accumulatorFunction arr.accumulateAndGet(idx, x, add); // Displaying the AtomicLongArray System.out.println("The array after update : " + arr); }} |
The array : [1, 2, 3, 4, 5] The array after update : [1, 2, 3, 4, 10]
Program 2:
// Java program that demonstrates// the accumulateAndGet() function import java.util.concurrent.atomic.AtomicLongArray;import java.util.function.LongBinaryOperator; public class GFG { public static void main(String args[]) { // Initializing an array long a[] = { 17, 22, 33, 44, 55 }; // Initializing an AtomicLongArray with array a AtomicLongArray arr = new AtomicLongArray(a); // Displaying the AtomicLongArray System.out.println("The array : " + arr); // Index where update is to be made int idx = 0; // Value to make operation with value at idx long x = 6; // Declaring the accumulatorFunction LongBinaryOperator sub = (u, v) -> u - v; // Updating the value at idx // applying accumulatorFunction arr.accumulateAndGet(idx, x, sub); // Displaying the AtomicLongArray System.out.println("The array after update : " + arr); }} |
The array : [17, 22, 33, 44, 55] The array after update : [11, 22, 33, 44, 55]
