praktikum-5/aufgabe-4

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -1,3 +1,4 @@
 .jdtls
 build
 result
+.direnv

build.xml

@@ -15,6 +15,7 @@
         <javac srcdir="${src.dir}" destdir="${classes.dir}"
                includeantruntime="false" debug="true">
             <compilerarg value="-Xlint:unchecked"/>
+            <exclude name="**/.direnv/**"/>
         </javac>
     </target>
 

praktikum-5/aufgabe4/Client.java

@@ -0,0 +1,53 @@
+package praktikum5.aufgabe4;
+
+import java.net.Socket;
+import java.net.UnknownHostException;
+import java.util.Scanner;
+import java.io.OutputStreamWriter;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+public class Client {
+    private int port;
+
+    public Client(int port) {
+        this.port = port;
+    }
+
+    public String send(String msg) throws IOException {
+        var socket = new Socket("localhost", port);
+        var out = socket.getOutputStream();
+        var in = socket.getInputStream();
+        var reader = new InputStreamReader(in);
+        var writer = new OutputStreamWriter(out);
+
+        writer.write(msg);
+        writer.flush();
+        socket.shutdownOutput();
+
+        var response = "";
+        var curr = reader.read();
+        while (curr != -1) {
+            response += (char)curr;
+            curr = reader.read();
+        }
+        reader.close();
+
+        return response;
+    }
+
+    public static void main(String[] args) {
+        try {
+            int port = 4711;
+            var client = new Client(port);
+            var reader = new Scanner(System.in);
+            while (true) {
+                var msg = reader.nextLine();
+                var response = client.send(msg);
+                System.out.println("Response: " + response);
+            }
+        } catch (Exception e) {
+            System.out.println(e);
+        }
+    }
+}

praktikum-5/aufgabe4/Server.java

@@ -0,0 +1,51 @@
+package praktikum5.aufgabe4;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+public class Server {
+    private ServerSocket socket;
+
+    public Server(ServerSocket socket) {
+        this.socket = socket;
+    }
+
+    public String echo() throws IOException {
+        var clientSocket = socket.accept();
+        var in = clientSocket.getInputStream();
+        var out = clientSocket.getOutputStream();
+        var reader = new InputStreamReader(in);
+        var writer = new OutputStreamWriter(out);
+
+        var msg = "";
+        var curr = reader.read();
+        while (curr != -1) {
+            msg += (char)curr;
+            curr = reader.read();
+        }
+
+        writer.write(msg);
+        writer.flush();
+        writer.close();
+
+        return msg;
+    }
+
+    public static void main(String[] args) {
+        try {
+            int port = 4711;
+            var socket = new ServerSocket(port);
+            var server = new Server(socket);
+            System.out.println("Listening on port " + port);
+            while (true) {
+                var msg = server.echo();
+                System.out.println("Request: " + msg);
+            }
+        } catch (Exception e) {
+            System.out.println(e);
+        }
+    }
+}