Shift Operators (<<, >>, >>> Unsigned Right Shift)

1Concept

Left shift << multiplies by powers of 2. Signed right shift >> divides by 2 preserving the sign bit. Unsigned right shift >>> shifts zeros into the high-order bit, useful for binary data.

2Architecture Diagram

5 << 1  ---> 10  (Multiply by 2)
-8 >> 1 ---> -4  (Signed right shift, preserves 1 bit)
-8 >>> 1---> 2147483644 (Unsigned right shift, zero fills high bit)

3Code Example

public class BitShiftDemo {
    public static void main(String[] args) {
        int val = 16;
        System.out.println("16 << 2 (16 * 4): " + (val << 2));
        System.out.println("16 >> 2 (16 / 4): " + (val >> 2));
        int neg = -16;
        System.out.println("-16 >> 2 (Signed): " + (neg >> 2));
        System.out.println("-16 >>> 2 (Unsigned): " + (neg >>> 2));
    }
}

4Expected Output

16 << 2 (16 * 4): 64
16 >> 2 (16 / 4): 4
-16 >> 2 (Signed): -4
-16 >>> 2 (Unsigned): 1073741820

5Key Takeaways

• ✓Unsigned right shift >>> is unique to Java and essential for cryptographic & binary packet processing.
• ✓Left shifting an integer past 31 bits wraps mod 32 in Java.
• ✓Bit shifting is significantly faster than standard division in low-level bytecode.