Connection-oriented, iterative server.

Question

Using the three-tier software architecture presented in this chapter, design and implement a client-server suite for the following protocol (it is not a well-known service): Each client sends to the server a name. The server accumulates the names received from successive clients (by appending each, with a linefeed (‘
’), to a static string). Upon receiving a name, the server sends the names that it has collected to the client. The figure below illustrates the sequence diagram of a session of the protocol.

Answer 1

Model the suite after the Echo*2 suite. The client sends one line only, but will need to read multiple lines, using syntax as follows:
```
public String getNames( String message) throws
SocketException, IOException {
String names = "", nextName = "";;
mySocket.sendMessage( message);
// now receive the names
nextName = mySocket.receiveMessage( );
while (nextName != null) {
names += nextName;
nextName = mySocket.receiveMessage( );
}
return names;
} //end getNames
```
The server accumulates the names in a string, in a manner similar to the description for (i).