Java AtomicReference getAndAccumulate()用法及代码示例

AtomicReference类的getAndAccumulate()方法用于原子地更新AtomicReference的当前值，并将给定的accumulatorFunction应用于当前值和给定值，并返回先前的值。 accumulatorFunction应该没有副作用，因为当尝试更新由于线程之间的争用而失败时，可能会重新应用accumulatorFunction。应用该函数时，将当前值作为其第一个参数，并将给定的update作为第二个参数。

用法:

public final E getAndAccumulate(E x,
     BinaryOperator<E> accumulatorFunction)

参数：此方法接受：

x这是更新的值，
accumulatorFunction这是两个参数的无副作用函数。

返回值：此方法返回prevoius值。

以下示例程序旨在说明getAndAccumulate()方法：
程序1:

// Java program to demonstrate 
// AtomicReference.getAndAccumulate() method 
  
import java.util.concurrent.atomic.*; 
import java.util.function.BinaryOperator; 
  
public class GFG { 
    public static void main(String args[]) 
    { 
  
        // AtomicReference with value 
        AtomicReference<Integer> ref 
            = new AtomicReference<>(3456); 
  
        // Value to apply getAndAccumulate 
        int x = 45654; 
  
        // Declaring the accumulatorFunction 
        // applying function to add value as string 
        BinaryOperator add 
            = (u, v) -> u.toString() + v.toString(); 
  
        // apply getAndAccumulate() 
        int value = ref.getAndAccumulate(x, add); 
  
        // print AtomicReference 
        System.out.println( 
            "The AtomicReference previous value:"
            + value); 
        System.out.println( 
            "The AtomicReference new value:"
            + ref.get()); 
    } 
}

输出：

程序2:

// Java program to demonstrate 
// AtomicReference.getAndAccumulate() method 
  
import java.util.concurrent.atomic.*; 
import java.util.function.BinaryOperator; 
  
public class GFG { 
    public static void main(String args[]) 
    { 
        // AtomicReference with value 
        AtomicReference<String> ref 
            = new AtomicReference<String>("GFG "); 
  
        // Value to apply getAndAccumulate 
        String x = "Welcome"; 
  
        // Declaring the accumulatorFunction 
        // applying function to add value as string 
        BinaryOperator add 
            = (u, v) -> v + " to " + u; 
  
        // apply getAndAccumulate() 
        String previousValue 
            = ref.getAndAccumulate(x, add); 
  
        // print AtomicReference 
        System.out.println( 
            "The AtomicReference previous value:"
            + previousValue); 
    } 
}

输出：

参考文献： https://docs.oracle.com/javase/10/docs/api/java/util/concurrent/atomic/AtomicReference.html#getAndAccumulate(V, java.util.function.BinaryOperator)

相关用法

注：本文由纯净天空筛选整理自AmanSingh2210大神的英文原创作品 AtomicReference getAndAccumulate() method in Java with Examples。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。