Using simple bitwise operations:
data[0] = (byte) (width & 0xFF);
data[1] = (byte) ((width >> 8) & 0xFF);
How it works:
& 0xFFmasks all but the lowest eight bits.>> 8discards the lowest 8 bits by moving all bits 8 places to the right.- The cast to byte is necessary because these bitwise operations work on an
intand return anint, which is a bigger data type thanbyte. The case is safe, since all non-zero bits will fit in thebyte. For more information, see Conversions and Promotions.
Edit: Taylor L correctly remarks that though >> works in this case, it may yield incorrect results if you generalize this code to four bytes (since in Java an int is 32 bits). In that case, it’s better to use >>> instead of >>. For more information, see the Java tutorial on Bitwise and Bit Shift Operators.