Convert Byte to binary in Java

Question

I am trying to convert a byte value to binary for data transfer. Basically, I am sending a value like \"AC\" in binary (\"10101100\") in a byte array where \"10101100\" is a

Answer 1

For converting hexidecimal into binary, you can use BigInteger to simplify your code.

public static void sendHex(OutputStream out, String hexString) throws IOException {
    byte[] bytes = new BigInteger("0" + hexString, 16).toByteArray();
    out.write(bytes, 1, bytes.length-1);
}

public static String readHex(InputStream in, int byteCount) throws IOException {
    byte[] bytes = new byte[byteCount+1];
    bytes[0] = 1;
    new DataInputStream(in).readFully(bytes, 1, byteCount);
    return new BigInteger(0, bytes).toString().substring(1);
}

---

Bytes are sent as binary without translation. It fact its the only type which doesn't require some form of encoding. As such there is nothing to do.

To write a byte in binary

OutputStream out = ...
out.write(byteValue);

InputStream in = ...
int n = in.read();
if (n >= 0) {
   byte byteValue = (byte) n;