Java two's complement binary to integer [duplicate]

Question

This question already has an answer here:

• 2's complement hex number to decimal in java 3 answers

I know that converting a decimal to binary with Integer.toBinaryString(355) = 0000000101100011 and Integer.toBinaryString(-355) = 1111111010011101 (where I take the lower 16 bits of the 32 bit result).

What I would like to do is the other way and take a 16-bit twos's complement binary string and to convert to decimal.

i.e.

0000000000110010 =  50
1111111111001110 = -50

Rather than 1111111111001110 = 65486

How would I do this?

Answer 1

You need to read the result into short.

short res = (short)Integer.parseInt("1111111111001110", 2);
System.out.println(res);

This prints -50.

Answer 2

Use a short? They occupy 16 bits.

http://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html