Java TCP How do you read a sent stream size (header) and keep reading based upon that size

Question

Given the following pseudo code. how would I do read in the given data

Answer 1

You can try JBBP

@Bin class Struct { byte [] payload; }
@Bin class ParsedStream { Struct [] structs; }
ParsedStream parsed = JBBPParser.prepare("structs[_] { ushort size; byte [size] payload; }").parse(theInStream).mapTo(ParsedStream.class);

Answer 2

Use DataInputStream to make your life easy.

DataInputStream in = new DataInputStream(socket.getInputStream());
short myShortStreamSize = in.readShort();
byte[] payload = new byte[myShortStreamSize];
in.readFully(payload);

Answer 3

Socket has a getInputStream() method. You would use the returned InputStream and read myShortStreamSize of bytes from it into a byte[], convert that into a int/long representing your payload size and then read into another, larger, new byte[payloadSize], the payload itself.