BAEL1053 - deep20jain@gmail.com - Broadcasting and Multicasting in Java (#2368)

* Adding code for java broadcasting and multicasting

* Changing multicast ip

* Adding code to iterate thorugh all network interfaces

* Formatting again and fixing bug

* Applying formatting rules on all classes

* Fixing formatting

core-java/src/test/java/com/baeldung/java/networking/udp/broadcast/BroadcastIntegrationTest.java

@@ -0,0 +1,39 @@
+package com.baeldung.java.networking.udp.broadcast;
+
+import org.junit.After;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static org.junit.Assert.assertEquals;
+
+public class BroadcastIntegrationTest {
+    private BroadcastingClient client;
+
+    @Test
+    public void whenBroadcasting_thenDiscoverExpectedServers() throws Exception {
+        int expectedServers = 4;
+        initializeForExpectedServers(expectedServers);
+
+        int serversDiscovered = client.discoverServers("hello server");
+        assertEquals(expectedServers, serversDiscovered);
+    }
+
+    private void initializeForExpectedServers(int expectedServers) throws Exception {
+        for (int i = 0; i < expectedServers; i++) {
+            new BroadcastingEchoServer().start();
+        }
+
+        client = new BroadcastingClient(expectedServers);
+    }
+
+    @After
+    public void tearDown() throws IOException {
+        stopEchoServer();
+        client.close();
+    }
+
+    private void stopEchoServer() throws IOException {
+        client.discoverServers("end");
+    }
+}

core-java/src/test/java/com/baeldung/java/networking/udp/multicast/MulticastIntegrationTest.java

@@ -0,0 +1,39 @@
+package com.baeldung.java.networking.udp.multicast;
+
+import org.junit.After;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static org.junit.Assert.assertEquals;
+
+public class MulticastIntegrationTest {
+    private MulticastingClient client;
+
+    @Test
+    public void whenBroadcasting_thenDiscoverExpectedServers() throws Exception {
+        int expectedServers = 4;
+        initializeForExpectedServers(expectedServers);
+
+        int serversDiscovered = client.discoverServers("hello server");
+        assertEquals(expectedServers, serversDiscovered);
+    }
+
+    private void initializeForExpectedServers(int expectedServers) throws Exception {
+        for (int i = 0; i < expectedServers; i++) {
+            new MulticastEchoServer().start();
+        }
+
+        client = new MulticastingClient(expectedServers);
+    }
+
+    @After
+    public void tearDown() throws IOException {
+        stopEchoServer();
+        client.close();
+    }
+
+    private void stopEchoServer() throws IOException {
+        client.discoverServers("end");
+    }
+}