javadoc, clear warnings

examples/src/UdpExamples/MulticastUdpReceiver.java

@@ -13,8 +13,13 @@ import java.util.logging.Logger;
  * @author mcgredo
  * @author brutzman
  */
-public class MulticastUdpReceiver {
-
+public class MulticastUdpReceiver
+{
+    /** Default constructor */
+    public MulticastUdpReceiver()
+    {
+        // default constructor
+    }
     // reserved range for all IPv4 multicast: 224.0.0.0 through 239.255.255.255
     // https://en.wikipedia.org/wiki/Multicast_address
     // https://www.iana.org/assignments/multicast-addresses/multicast-addresses.xhtml

examples/src/UdpExamples/MulticastUdpSender.java

@@ -16,6 +16,11 @@ import java.util.logging.Logger;
  */
 public class MulticastUdpSender
 {
+    /** Default constructor */
+    public MulticastUdpSender()
+    {
+        // default constructor
+    }
     // reserved range for all IPv4 multicast: 224.0.0.0 through 239.255.255.255
     // https://www.iana.org/assignments/multicast-addresses/multicast-addresses.xhtml
 

examples/src/UdpExamples/UnicastUdpReceiver.java

@@ -16,8 +16,13 @@ import java.net.*;
  * @author mcgredo
  * @author brutzman
  */
-public class UnicastUdpReceiver 
+public class UnicastUdpReceiver
 {
+    /** Default constructor */
+    public UnicastUdpReceiver()
+    {
+        // default constructor
+    }
 //  public static final int        SENDING_PORT = 1414;        // port used by UdpSender, unneeded here
     /** socket value of shared interest */
     public static final int      UDP_PORT = 1415;        // sharable

examples/src/UdpExamples/UnicastUdpSender.java

@@ -19,6 +19,11 @@ import java.net.*;
  */
 public class UnicastUdpSender 
 {
+    /** Default constructor */
+    public UnicastUdpSender()
+    {
+        // default constructor
+    }
     private static final String            MY_NAME = System.getProperty("user.name"); // guru incantation   8)
 //  public  static final int          SENDING_PORT = 1414; // not needed, can let system choose an open local port
     /** socket value of shared interest */