[Java] bit & shift 연산

& : 두 비트가 같으면 1, 다르면 0

| : 두 비트중 하나라도 1이면 1, 아니면 0

^ : 두 비트가 다르면 1, 같으면 0

~ : 1 이면 0, 0 이면 1

<< : 왼쪽으로 이동후 오른쪽 비트를 0 으로 채움

>> : 오른쪽으로 이동후  왼쪽 비트를 왼쪽 첫 비트와 같은 비트로 채움 (0이면 0으로 채우고 1이면 1로 채움)

>>> : 오른쪽으로 이동후 왼쪽 비트를 0 으로 채움

source

public class TestMain { public static void main(String[] args) throws Exception { System.out.println(" 25        : " + lpad8(Integer.toBinaryString(0xff & 25))); System.out.println(" 255       : " + lpad8(Integer.toBinaryString(0xff & 255))); System.out.println(" 25 & 255  : " + lpad8(Integer.toBinaryString(0xff & (25 & 255)))); System.out.println(); System.out.println(" 25        : " + lpad8(Integer.toBinaryString(0xff & 25))); System.out.println(" 0         : " + lpad8(Integer.toBinaryString(0xff & 0))); System.out.println(" 25 | 0    : " + lpad8(Integer.toBinaryString(0xff & (25 | 0)))); System.out.println(); System.out.println(" 25        : " + lpad8(Integer.toBinaryString(0xff & 25))); System.out.println(" 255       : " + lpad8(Integer.toBinaryString(0xff & 255))); System.out.println(" 25 | 255  : " + lpad8(Integer.toBinaryString(0xff & (25 | 255)))); System.out.println(); System.out.println(" 25        : " + lpad8(Integer.toBinaryString(0xff & 25))); System.out.println(" 255       : " + lpad8(Integer.toBinaryString(0xff & 255))); System.out.println(" 25 ^ 255  : " + lpad8(Integer.toBinaryString(0xff & (25 ^ 255)))); System.out.println(); System.out.println(" 25        : " + lpad8(Integer.toBinaryString(0xff & 25))); System.out.println(" ~25       : " + lpad8(Integer.toBinaryString(0xff & ~25))); System.out.println(); System.out.println(" 255       : " + lpad8(Integer.toBinaryString(0xff & 255))); System.out.println(" ~255      : " + lpad8(Integer.toBinaryString(0xff & ~255))); System.out.println(); System.out.println(" 256       : " + lpad32(Integer.toBinaryString(256))); System.out.println(" 256 <<  2 : " + lpad32(Integer.toBinaryString(256 << 2))); System.out.println(" 256 >>  2 : " + lpad32(Integer.toBinaryString(256 >> 2))); System.out.println(" 256 >>> 2 : " + lpad32(Integer.toBinaryString(256 >>> 2))); System.out.println(); System.out.println("-256       : " + lpad32(Integer.toBinaryString(-256))); System.out.println("-256 <<  2 : " + lpad32(Integer.toBinaryString(-256 << 2))); System.out.println("-256 >>  2 : " + lpad32(Integer.toBinaryString(-256 >> 2))); System.out.println("-256 >>> 2 : " + lpad32(Integer.toBinaryString(-256 >>> 2))); } public static String lpad8(Object obj) { String str = String.valueOf(obj); while (str.length() < 8) { str = "0" + str; } return ">" + str + "<"; } public static String lpad32(Object obj) { String str = String.valueOf(obj); while (str.length() < 32) { str = "0" + str; } return ">" + str + "<"; } }

console

25        : >00011001<  255       : >11111111<  25 & 255  : >00011001<  25        : >00011001<  0         : >00000000<  25 | 0    : >00011001<  25        : >00011001<  255       : >11111111<  25 | 255  : >11111111<  25        : >00011001<  255       : >11111111<  25 ^ 255  : >11100110<  25        : >00011001<  ~25       : >11100110<  255       : >11111111<  ~255      : >00000000<  256       : >00000000000000000000000100000000<  256 <<  2 : >00000000000000000000010000000000<  256 >>  2 : >00000000000000000000000001000000<  256 >>> 2 : >00000000000000000000000001000000< -256       : >11111111111111111111111100000000< -256 <<  2 : >11111111111111111111110000000000< -256 >>  2 : >11111111111111111111111111000000< -256 >>> 2 : >00111111111111111111111111000000<