Merge branch 'master' of https://github.com/Maiklins/tutorials into JAVA-7244-Review_log_statements_for_projects

 Conflicts:

	algorithms-searching/src/test/java/com/baeldung/algorithms/quadtree/QuadTreeSearchUnitTest.java

core-java-modules/core-java-networking-3/README.md

@@ -8,4 +8,5 @@ This module contains articles about networking in Java
 - [Downloading Email Attachments in Java](https://www.baeldung.com/java-download-email-attachments)
 - [Connection Timeout vs. Read Timeout for Java Sockets](https://www.baeldung.com/java-socket-connection-read-timeout)
 - [Find Whether an IP Address Is in the Specified Range or Not in Java](https://www.baeldung.com/java-check-ip-address-range)
+- [Find the IP Address of a Client Connected to a Server](https://www.baeldung.com/java-client-get-ip-address)
 - [[<-- Prev]](/core-java-modules/core-java-networking-2)

core-java-modules/core-java-networking-3/pom.xml

@@ -11,7 +11,6 @@
         <groupId>com.baeldung.core-java-modules</groupId>
         <artifactId>core-java-modules</artifactId>
         <version>0.0.1-SNAPSHOT</version>
-        <relativePath>../pom.xml</relativePath>
     </parent>
 
     <dependencies>
@@ -37,9 +36,8 @@
             <scope>test</scope>
         </dependency>
         <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <version>4.11</version>
+            <groupId>org.junit.vintage</groupId>
+            <artifactId>junit-vintage-engine</artifactId>
             <scope>test</scope>
         </dependency>
         <dependency>

core-java-modules/core-java-networking-3/src/main/java/com/baeldung/clientaddress/ApplicationClient.java

@@ -0,0 +1,39 @@
+package com.baeldung.clientaddress;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.Socket;
+
+public class ApplicationClient {
+
+    private Socket clientSocket;
+    private PrintWriter out;
+    private BufferedReader in;
+
+    public void connect(String ip, int port) throws IOException {
+        clientSocket = new Socket(ip, port);
+        out = new PrintWriter(clientSocket.getOutputStream(), true);
+        in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
+    }
+
+    public void sendGreetings(String msg) throws IOException {
+        out.println(msg);
+        String reply = in.readLine();
+        System.out.println("Reply received from the server :: " + reply);
+    }
+
+    public void disconnect() throws IOException {
+        in.close();
+        out.close();
+        clientSocket.close();
+    }
+
+    public static void main(String[] args) throws IOException {
+        ApplicationClient client = new ApplicationClient();
+        client.connect(args[0], Integer.parseInt(args[1])); // IP address and port number of the server
+        client.sendGreetings(args[2]); // greetings message
+        client.disconnect();
+    }
+}

core-java-modules/core-java-networking-3/src/main/java/com/baeldung/clientaddress/ApplicationServer.java

@@ -0,0 +1,51 @@
+package com.baeldung.clientaddress;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.InetSocketAddress;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+public class ApplicationServer {
+
+    private ServerSocket serverSocket;
+    private Socket connectedSocket;
+    private PrintWriter out;
+    private BufferedReader in;
+
+    public void startServer(int port) throws IOException {
+        serverSocket = new ServerSocket(port);
+        connectedSocket = serverSocket.accept();
+
+        InetSocketAddress socketAddress = (InetSocketAddress) connectedSocket.getRemoteSocketAddress();
+        String clientIpAddress = socketAddress.getAddress()
+            .getHostAddress();
+        System.out.println("IP address of the connected client :: " + clientIpAddress);
+
+        out = new PrintWriter(connectedSocket.getOutputStream(), true);
+        in = new BufferedReader(new InputStreamReader(connectedSocket.getInputStream()));
+        String msg = in.readLine();
+        System.out.println("Message received from the client :: " + msg);
+        out.println("Hello Client !!");
+
+        closeIO();
+        stopServer();
+    }
+
+    private void closeIO() throws IOException {
+        in.close();
+        out.close();
+    }
+
+    private void stopServer() throws IOException {
+        connectedSocket.close();
+        serverSocket.close();
+    }
+
+    public static void main(String[] args) throws IOException {
+        ApplicationServer server = new ApplicationServer();
+        server.startServer(5000);
+    }
+}