1.取模 (a mod b)

System.out.println("10 mod 3 = " + Math.floorMod(10, 3));

System.out.println("10 mod (-3) = " + Math.floorMod(10, -3));

System.out.println("(-10) mod 3 = " + Math.floorMod(-10, 3));

System.out.println("(-10) mod (-3) = " + Math.floorMod(-10, -3));

结果

取模运算

结论

取模运算结果的符号与b的符号一致。

2.取余(a % b)

System.out.println("10 % 3 = " + (10 % 3));

System.out.println("10 % (-3) = " + (10 % (-3)));

System.out.println("(-10) % 3 = " + ((-10) % 3));

System.out.println("(-10) % (-3) = " + ((-10) % (-3)));

结果

取余

结论

取余运算结果的符号与a的符号一致。

3.左移(a << b)

// -----------integer--------------

System.out.println("10 << 3 = " + (10 << 3));

System.out.println("10 << (-3) = " + (10 << (-3)));

System.out.println("10 << 29 = " + (10 << 29));

System.out.println("(-10) << 3 = " + ((-10) << 3));

System.out.println("(-10) << (-3) = " + ((-10) << (-3)));

System.out.println("(-10) << 29 = " + ((-10) << 29));

// ----------- long --------------

System.out.println("10L << 3 = " + (10L << 3));

System.out.println("10L << (-3) = " + (10L << (-3)));

System.out.println("10L << 61 = " + (10L << (-3)));

System.out.println("(-10L) << 3 = " + ((-10L) << 3));

System.out.println("(-10L) << (-3) = " + ((-10L) << (-3)));

System.out.println("(-10L) << 61 = " + ((-10L) << (-3)));

结果

左移

结论

a扩大相应倍数，且结果符号保持不变右侧补0，当b<0时，取(b mod 32)或(b mod 64)。

4.右移(a >> b)

// -----------integer--------------

System.out.println("10 >> 3 = " + (10 >> 3));

System.out.println("10 >> (-3) = " + (10 >> (-3)));

System.out.println("10 >> 29 = " + (10 >> 29));

System.out.println("(-10) >> 3 = " + ((-10) >> 3));

System.out.println("(-10) >> (-3) = " + ((-10) >> (-3)));

System.out.println("(-10) >> 29 = " + ((-10) >> 29));

// ----------- long --------------

System.out.println("10L >> 3 = " + (10L >> 3));

System.out.println("10L >> (-3) = " + (10L >> (-3)));

System.out.println("10L >> 61 = " + (10L >> (-3)));

System.out.println("(-10L) >> 3 = " + ((-10L) >> 3));

System.out.println("(-10L) >> (-3) = " + ((-10L) >> (-3)));

System.out.println("(-10L) >> 61 = " + ((-10L) >> (-3)));

结果

右移

结论

a缩小相应倍数，且结果符号保持不变左侧补0，当b<0时，取(b mod 32)或(b mod 64)。

5.无符号右移(a >>> b)

// -----------integer--------------

System.out.println("10 >>> 3 = " + (10 >>> 3));

System.out.println("10 >>> (-3) = " + (10 >>> (-3)));

System.out.println("10 >>> 29 = " + (10 >>> 29));

System.out.println("(-10) >>> 3 = " + ((-10) >>> 3));

System.out.println("(-10) >>> (-3) = " + ((-10) >>> (-3)));

System.out.println("(-10) >>> 29 = " + ((-10) >>> 29));

// ----------- long --------------

System.out.println("10L >>> 3 = " + (10L >>> 3));

System.out.println("10L >>> (-3) = " + (10L >>> (-3)));

System.out.println("10L >>> 61 = " + (10L >>> (-3)));

System.out.println("(-10L) >>> 3 = " + ((-10L) >>> 3));

System.out.println("(-10L) >>> (-3) = " + ((-10L) >>> (-3)));

System.out.println("(-10L) >>> 61 = " + ((-10L) >>> (-3)));

结果

无符号右移

结论

a缩小相应倍数，左侧所有位补0，当b<0时，取(b mod 32)或(b mod 64)。

6.其他整数的位移(char、byte、short)

System.out.println("(char)10 << (-3) = " + ((char)10 << (-3)));

System.out.println("(byte)10 << (-3) = " + ((byte)10 << (-3)));

System.out.println("(short)10 << (-3) = " + ((short)10 << (-3)));

System.out.println("10 << (-3) = " + (10 << (-3)));

System.out.println("10 << 29 = " + (10 << 29));

结果

其他整数位移

结论

其他整数(char、byte、short)位移时，先转化为int，然后再按照int的位移规则进行位移，并且其结果是int类型。

7.浮点数位移(float、double)

浮点数(float、double)不支持位移操作。