set AtomicInteger Bit If Unset By Value - Java java.util.concurrent.atomic

Java examples for java.util.concurrent.atomic:AtomicInteger

  1. HOME
  2. Java
  3. java.util.concurrent.atomic
  4. AtomicInteger

Description

set AtomicInteger Bit If Unset By Value

Demo Code


//package com.java2s;
import java.util.concurrent.atomic.AtomicInteger;

public class Main {
    /**/*  ww w .  jav a  2s.  c  o m*/
     * @return true if operation is conducted, false if the bit is already set.
     * @param ai the AtomicInteger to operate on
     * @param value from the value get the index of the set bit from the least significant bit. Do the operation on that
     *          index.
     * */
    public static boolean setBitIfUnsetByValue(final AtomicInteger ai,
            final int value) {
        return setBitIfUnsetByIndex(ai,
                Integer.numberOfTrailingZeros(value));
    }

    /**
     * @return true if operation is conducted, false if the bit is already set.
     * @param ai the AtomicInteger to operate on
     * @param n the nth bit from the least significant bit to compare
     * */
    public static boolean setBitIfUnsetByIndex(final AtomicInteger ai,
            final int n) {
        if (n >= Integer.SIZE) {
            throw new IllegalArgumentException(
                    "Out of int bit index boundary (31)");
        }
        int bitInt = 1 << n;
        int oldValue = ai.get();
        int newValue = oldValue | bitInt;
        while (newValue != oldValue
                && !ai.compareAndSet(oldValue, newValue)) {
            oldValue = ai.get();
            newValue = oldValue | bitInt;
        }
        return newValue != oldValue;
    }
}

Related Tutorials