Java中的 AtomicReference 累积AndGet() 方法及示例

AtomicReference类的accumulateAndGet()方法用于使用将给定 accumulatorFunction 应用于当前值和给定值的结果以原子方式更新 AtomicReference 的当前值，并返回更新后的值。 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，它可能会被重新应用。

句法：

public final E accumulateAndGet(E x,
     BinaryOperator accumulatorFunction)

参数：此方法接受：

• x是更新后的值，并且
• accumulatorFunction是两个参数的无副作用函数。

返回值：该方法返回更新后的值。

下面的程序说明了 accumulateAndGet() 方法：
方案一：

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

输出：

方案二：

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

输出：

参考： https: Java Java )