Java sockets: request-response template with object flows

Question

My goal is to implement a simple Java socket-based request-response template that is used to request an object from the server.

It should work as follows:

• The client sends a message to the server on which the server is evaluating. Depending on what he got a certain function. This part works.
• The server writes the requested data to an ObjectOutputStream. This also works, at least I did not receive an error message.
• The client reads data from the input stream until it receives a CLOSE message, which makes the program end the while loop. It does not work as it should.

Here are some pieces of critical code:

// Client (Sending request) *** WORKS objectOutputStream.writeInt(GET_OBJECT); objectOutputStream.flush(); // Server (After receipt of the message) *** WORKS objectOutputStream.writeInt(object); objectOutputStream.writeInt(CLOSE); // Client (Reading the answer from the server) *** WRONG while(true){ int i = objectInputStream.readInt(); if(i == CLOSE) break; } 

Answer 1

• You have flush on the client side and the message is received by the server;
• you are missing flush on the server side and the message will not be received by the client.

I notice a pattern in these two facts ...