public void routeMessage(byte[] data, int mode) { logger.debug(mode); logger.debug(Integer.toBinaryString(mode)); byte[] message = new byte[8]; ByteBuffer byteBuffer = ByteBuffer.allocate(4); ByteArrayOutputStream baoStream = new ByteArrayOutputStream(); DataOutputStream doStream = new DataOutputStream(baoStream); try { doStream.writeInt(mode); } catch (IOException e) { logger.debug("Error converting mode from integer to bytes.", e); return; } byte [] bytes = baoStream.toByteArray(); bytes[0] = (byte)((mode >>> 24) & 0x000000ff); bytes[1] = (byte)((mode >>> 16) & 0x000000ff); bytes[2] = (byte)((mode >>> 8) & 0x00000ff); bytes[3] = (byte)(mode & 0x000000ff); //bytes = byteBuffer.array(); for (byte b : bytes) { logger.debug(b); } for (int i = 0; i < 4; i++) { //byte tmp = (byte)(mode >> (32 - ((i + 1) * 8))); message[i] = bytes[i]; logger.debug("mode, " + i + ": " + Integer.toBinaryString(message[i])); message[i + 4] = data[i]; } broker.routeMessage(message); } I've tried different ways (as you can see from the commented code) to convert the mode to four bytes to send it via a socket to another application. It works well with integers up to 127 and then again with integers over 256. I believe it has something to do with Java types being signed but don't seem to get it to work. Here are some examples of what the program prints. 127 1111111 0 0 0 127 mode, 0: 0 mode, 1: 0 mode, 2: 0 mode, 3: 1111111 128 10000000 0 0 0 -128 mode, 0: 0 mode, 1: 0 mode, 2: 0 mode, 3: 11111111111111111111111110000000 211 11010011 0 0 0 -45 mode, 0: 0 mode, 1: 0 mode, 2: 0 mode, 3: 11111111111111111111111111010011 306 100110010 0 0 1 50 mode, 0: 0 mode, 1: 0 mode, 2: 1 mode, 3: 110010 How is it suddenly possible for a byte to store 32 bits? How could I fix this?