com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure Last packet sent to the server was 1 ms ago. in eclipse -

i did jdbc connectivity lastnight not working today..although have'nt changed code or else. please me out. code is:

package programs; import java.sql.*;  class dbase     {     public static void main(string args[])         {         try             {             class.forname("com.mysql.jdbc.driver");             connection c=drivermanager.getconnection("jdbc:mysql://localhost:3306/scms","root","scms");             if(c!=null)             system.out.println("connection o.k.");             else             system.out.println("connection failed!");             }         catch(exception e)         {             system.out.println(e);         }         }     }