A complete collection of common Java operators

1. Java-supported bit operators

Java provides 7 bit operators:

2. Detailed explanation of bit operations

(1) Bitwise and (&)

• rule: When both bits are 1, the result is 1, otherwise it is 0.

• Example：

  int a = 5;    // Binary: 0101int b = 3;    // Binary: 0011int c = a & b; // Binary: 0001 → 1(c); // Output：1

• application：

  • Judge odd and even:(n & 1) == 0→ Even number.

(2) bitwise or (|)

• rule: When one of the two bits is 1, the result is 1.

• Example：

  int a = 5;    // 0101
  int b = 3;    // 0011
  int c = a | b; // 0111 → 7
  (c); // Output：7

• application：

  • Merge multiple flag bits (such asREAD | WRITE | EXECUTE）。

(3) Bitwise XOR (^)

• rule: The two bits are different, the result is 1, otherwise it is 0.

• Example：

  int a = 5;    // 0101
  int b = 3;    // 0011
  int c = a ^ b; // 0110 → 6
  (c); // Output：6

• characteristic：

  • a ^ a = 0(The same number is XOR 0).

  • a ^ 0 = a(Any number is exclusive or unchanged with 0).

• application：

  • Exchange two numbers (no temporary variables):

    int x = 5, y = 3;
    x = x ^ y;
    y = x ^ y; // y = (x ^ y) ^ y = x
    x = x ^ y; // x = (x ^ y) ^ x = y
    (x + ", " + y); // Output：3, 5

(4) Bitwise invert (~)

• rule: Inverse all bits (0→1, 1→0).

• Example：

  int a = 5;    // 0000 0101
  int b = ~a;   // 1111 1010 (complement code representation)(b); // Output：-6

• Notice：

  • Java uses complement to represent negative numbers.~5Actually it is-6。

(5) Move left (<<)

• rule: All bits move to the left, and the low bit is filled with 0.

• Example：

  int a = 5;    // 0000 0101
  int b = a << 1; // 0000 1010 → 10
  (b); // Output：10

• application：

  • Quick calculationa * 2^n(likea << 3 = a * 8）。

(6) Move right (>>)

• rule: All bits move to the right, and the high bit complements the sign bits (positive number is 0, negative number is 1).

• Example：

  int a = 5;    // 0000 0101
  int b = a >> 1; // 0000 0010 → 2
  int c = -5 >> 1; // 1111 1101 → -3
  (b + ", " + c); // Output：2, -3

• application：

  • Quick calculationa / 2^n(likea >> 2 = a / 4）。

(7) Unsigned right (>>>)

• rule: All bits move to the right, and the high bit is supplemented by 0 (not considering the sign bit).

• Example：

  int a = -5;    // 1111 1111 1111 1111 1111 1111 1111 1011
  int b = a >>> 1; // 0111 1111 1111 1111 1111 1111 1111 1101 → 2147483645
  (b); // Output：2147483645

• application：

  • Handle unsigned integers (Java does not have unsigned types, but can be used>>>Simulation).

3. Common uses of bit operations

(1) Judgment odd and even

if ((n & 1) == 0) {
    ("even");
} else {
    ("odd number");
}

(2) Exchange two numbers

int x = 5, y = 3;
x = x ^ y;
y = x ^ y;
x = x ^ y;
(x + ", " + y); // Output：3, 5

(3) Calculate the absolute value

int a = -5;
int abs = (a ^ (a >> 31)) - (a >> 31);
(abs); // Output：5

(4) Determine whether it is a power of 2

boolean isPowerOfTwo = (n & (n - 1)) == 0;
(isPowerOfTwo); // 8 → true, 7 → false

(5) Quick calculation 2^n

int power = 1 << n; // 2^n
(power); // n=3 → 8

4. Summary

This is the end of this article about the bit operators of common Java operators. For more information about Java bit operators, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!