public class IntegerArrayTest {
public static void main(String[] args) {
Integer a=1;
Integer b=13;
Integer c=25;
/**
* 0000 0000 0000 0000 0000 0000 0000 0000
* 0000 0000 0000 0000 0000 0000 0000 0001 0的个数为31 1
* 0000 0000 0000 0000 0000 0000 0000 1101 0的个数为28 13
* 0000 0000 0000 0000 0000 0000 0001 1001 0的个数为27 25
* a的二进制为=1 最左边开始数起连续0的个数为31
* b的二进制为=1101 最左边开始数起连续0的个数为28
* c的二进制为=11001 最左边开始数起连续0的个数为27
*/
System.out.println("a的二进制为="+Integer.toBinaryString(a)+" 最左边开始数起连续0的个数为"+Integer.numberOfLeadingZeros(a));
System.out.println("b的二进制为="+Integer.toBinaryString(b)+" 最左边开始数起连续0的个数为"+Integer.numberOfLeadingZeros(b));
System.out.println("c的二进制为="+Integer.toBinaryString(c)+" 最左边开始数起连续0的个数为"+Integer.numberOfLeadingZeros(c));
}
}
public class AtomicIntegerArray implements java.io.Serializable {
private static final long serialVersionUID = 2862133569453604235L;
private static final Unsafe unsafe = Unsafe.getUnsafe();
private static final int base = unsafe.arrayBaseOffset(int[].class);
private static final int shift;
private final int[] array;
static {
int scale = unsafe.arrayIndexScale(int[].class);
if ((scale & (scale - 1)) != 0)
throw new Error("data type scale not a power of two");
shift = 31 - Integer.numberOfLeadingZeros(scale);
}
}
1 /**
2 * 原子性的设置一个值
3 */
4 public final void set(int i, int newValue) {
5 unsafe.putIntVolatile(array, checkedByteOffset(i), newValue);
6 }
/**
* 原子性的设置一个值
*/
public final void set(int newValue) {
value = newValue;
}
public static void automicIntegerArray() {
/**
* 创建一个原子性的数组,长度为5
*/
AtomicIntegerArray atomicArray = new AtomicIntegerArray(5);
/**
* 设置第一个元素的值为5
*/
atomicArray.set(0, 5);
/**
* 第一个元素减去1
*/
int current = atomicArray.decrementAndGet(0);
System.out.println("current = " + current);//current = 4
}
/**
* 创建一个原子性整※数组，并且长度为length;而且初始值都为0
* elements initially zero.
*/
public AtomicIntegerArray(int length) {
array = new int[length];
}
原文：https://www.cnblogs.com/gosaint/p/9053871.html