The problem:
Client doesn't receive any message.
Here is the full code for both client and server:
CLIENT
public class Client extends Socket{
public Client(String hostName, int port) throws UnknownHostException, IOException {
super(hostName,port);
BufferedReader in = new BufferedReader(new InputStreamReader(getInputStream()));
while(true) {
String line = in.readLine();
System.out.println("Text received: " + line);
}
}
SERVER
public final class Server extends ServerSocket{
public Server(int port) throws IOException {
super(port);
System.out.println("Server waiting for client 1");
Socket client1 = accept();
PrintWriter writer = new PrintWriter(client1.getOutputStream(), true);
writer.write("Hello user 1");
System.out.println("Server waiting for client 2");
Socket client2 = accept();
PrintWriter writer2 = new PrintWriter(client2.getOutputStream(), true);
writer2.write("Hello user 2");
System.out.println("Clients connected");
}
- I start the server to listen to port 4444
- I start the clients with hostname of "localhost" and port 4444
You have to include a newline character at the end of the message, and also flush the PrintWriter if the connection is not immediately altered, forcing an automatic flush:
writer.write("Hello user 1\n");
writer.flush();
EDIT:
It is possible to enable automatic flushing on a PrintWriter using the constructor new PrintWriter(someOutputStream, true)
However, as explained in the documentation:
if automatic flushing is enabled it will be done only when one of the println, printf, or format methods is invoked, rather than whenever a newline character happens to be output
This means that even with automatic flushing, the PrintWriter would still have to be manually flushed after write
is called, and a newline character (\n
) would still have to be included at the end of the string.
EDIT 2:
Here is a small example of a fully functional client/server application:
Client:
public static void main(String[] args){
try{
Socket socket = new Socket(HOST_ADDRESS, PORT);
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
System.out.println(bufferedReader.readLine());
bufferedReader.close();
socket.close();
}catch(IOException e){}
}
Server:
public static void main(String[] args){
try{
ServerSocket serverSocket = new ServerSocket(PORT);
Socket socket = serverSocket.accept();
PrintWriter printWriter = new PrintWriter(socket.getOutputStream());
printWriter.write("Hello user!\n");
printWriter.flush();
printWriter.close();
socket.close();
serverSocket.close();
}catch(IOException e){}
}