java - How to close a server port after we are done using it? -

note: found similar question here:

how close port after using server sockets

but did not find satisfactory answer there.

here code client program:

package hf;  import java.io.*; import java.net.*;  public class dailyadviceclient  {     private static final int chatport = 4242;     public static void main(string[] args)     {         dailyadviceclient client = new dailyadviceclient();         client.go();     }      private void go()     {         try         {             socket socket = new socket("127.0.0.1",chatport);             inputstreamreader inputstream = new inputstreamreader(socket.getinputstream());             bufferedreader bufferedreader = new bufferedreader(inputstream);              string advice = bufferedreader.readline();             system.out.println("advice received client today "+advice);              bufferedreader.close();         }         catch(exception e)         {             system.out.println("failed connect server");         }     } } 

and here code server program:

package hf;  import java.io.*; import java.net.*;  public class dailyadviceserver  {     private string[] advicelist = {"take smaller bites",             "go tight jeans. no not make fat.",             "one word: inappropriate",              "just today, honest. tell boss *really* think",              "you might want rethink haircut."};     private static final int chatport = 4242;      public static void main(string[] args)     {         dailyadviceserver server = new dailyadviceserver();         server.go();     }      private void go()     {         try         {             serversocket serversocket = new serversocket(chatport);              while(true)             {                 socket socket = serversocket.accept();                  printwriter writer = new printwriter(socket.getoutputstream());                  string advice = gettodaysadvice();                  writer.println(advice);                 writer.close();             }         }         catch(exception e)         {             system.out.println("error in establishing connection client");         }     }      private string gettodaysadvice()     {         string advice = null;          int randomindex = (int) (math.random()*advicelist.length);         advice = advicelist[randomindex];         return advice;     } } 

in application, whenever client program connects server program, receives string contains advice day.

when run

netstat -an 

in command prompt of windows computer suggested in 1 of answers in aforementioned link, message port 4242

listening 

how close port , make available future re-use?

to rid of listening port have call serversocket.close().