&

• 逻辑与，& 两边的表达式都会进行运算
• 整数的位运算符

&&

• 短路与，&& 左边的表达式结果为 false 时，&& 右边的表达式不参与计算

package constxiong.interview;

/**
 * 测试 & &&
 * @author ConstXiong
 */
public class TestAnd {

    public static void main(String[] args) {
        int x = 10;
        int y = 9;
        if (x == 9 & ++y > 9) {
        }
        System.out.println("x = " + x + ", y = " + y);
        
        int a = 10;
        int b = 9;
        if (a == 9 && ++b > 9) {//a == 9 为 false，所以 ++b 不会运算，b=9
        }
        System.out.println("a = " + a + ", b = " + b);
        
        //00000000000000000000000000000001
        //00000000000000000000000000000010
        //=
        //00000000000000000000000000000000
        System.out.println(1 & 2);//打印0
    }
    
}

打印

x = 10, y = 10
a = 10, b = 9
0