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Do some simple networking

Two simple Java programs, that send characters over the network.

Client

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.Socket;

/**
 * Socket-Demo
 */
public class ConversionClient
{
    // ConversionClient-Programm: \
    // Liest eine Zeile von der Tastatur, und sendet sie an den Server und\
    // bekommt von ihm eine Zeile zurück.\
    // Speichern als: ConversionClient.java\
    // Kompilieren: javac ConversionClient.java\
    // Starten: java ConversionClient\
    // In Zeile 11 muss der richtige Servername stehen bzw. "localhost",\
    // falls der Server auf demselben Rechner läuft.\
    // Der Server muss natürlich vorher gestartet sein.\
    public static void main(final String[] argv) throws Exception
    {
        String sentence;
        String modifiedSentence;
        BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
        Socket clientSocket = new Socket("localhost", 6789);
        DataOutputStream outToServer = new DataOutputStream(clientSocket.getOutputStream());
        BufferedReader inFromServer = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
        sentence = inFromUser.readLine();
        outToServer.writeBytes(sentence + System.lineSeparator());
        modifiedSentence = inFromServer.readLine();
        System.out.println("FROM SERVER:" + modifiedSentence);
        clientSocket.close();
    }
}

Server

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * Socket-Demo
 */
//ConversionServer-Programm:\
//Speichern als: ConversionServer.java\
//Kompilieren: javac ConversionServer.java\
//Starten: java ConversionServer\
public class ConversionServer
{
    public static void main(final String[] argv) throws Exception
    {
        String clientSentence;
        String capitalizedSentence;
        ServerSocket welcomeSocket = new ServerSocket(6789);
        while (true)
        {
            Socket connectionSocket = welcomeSocket.accept();
            BufferedReader inFromClient = new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
            DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
            clientSentence = inFromClient.readLine();
            capitalizedSentence = clientSentence.toUpperCase() + System.lineSeparator();
            outToClient.writeBytes(capitalizedSentence);
        }
    }

}