Java function - convert a byte into a binary string

byteToString

public static String byteToString(byte b) {
    byte[] masks = { -128, 64, 32, 16, 8, 4, 2, 1 };
	StringBuilder builder = new StringBuilder();
    for (byte m : masks) {
        if ((b & m) == m) {
            builder.append('1');
        } else {
            builder.append('0');
        }
    }
    return builder.toString();
}