Is there a way to ask a DataInputStream, if it has content to read? .readByte() will just hang it, waiting for a byte to be read :( Or do I always have to send a Dummy-Byte, to make sure it always sees something?
dis.available();
Returns: an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking.
Is this what you looking for?
also check answers here. You might get even more informations. "available" of DataInputStream from Socket