Java Database Connectivity Module

/*
Connection Class for MySQL by Richard Niescior
*/
public class DBConnectionHandler {

    java.sql.Connection link;
    String u,p,l;
    public void popup(String b, String c, int d){
        javax.swing.JOptionPane.showMessageDialog(null,b,c,d);
    }
    public java.sql.Connection dbcon(String a,String b,String c) throws java.sql.SQLException{
    return java.sql.DriverManager.getConnection(a,b,c);
}
public DBConnectionHandler(String ... a){
    if(a.length == 0)popup("Invalid Parameters","Cannot establish connection",2);
    if(a.length >= 1)
    l=a[0];
    if(a.length <=3){
    u = a[1];
    p = a[2];
}

    try{
        Class.forName("com.mysql.jdbc.Driver");
link = dbcon(l,u,p);
}catch( java.sql.SQLException e){
    e.printStackTrace();
    popup(e.getLocalizedMessage(), e.getErrorCode()+"",2);
   // exit(0)

        }catch(ClassNotFoundException e){
    popup("MYSQL Driver Library is missing! Consult the developer for more information!","Driver Missing!",2);
    //exit(0)
}

}
public  java.sql.ResultSet query(String sql){
    java.sql.ResultSet rs = null;
    try{
   rs = ((java.sql.Statement)link.createStatement()).executeQuery(sql);

   return rs;
}catch( java.sql.SQLException e){
    popup(e.getLocalizedMessage()+"\n\n A connection will be attempted again","Connection error",2);
   try{
       link = dbcon(l,u,p);
        rs = ((java.sql.Statement)link.createStatement()).executeQuery(sql);

   return rs;
   }
   catch( java.sql.SQLException em){
       popup(em.getLocalizedMessage()+"\n\nReconnection failed! Program will exit.","Reconnect failed!",2);
       System.exit(0);

   }
}
    return rs;
}
public void update(String sql){

    try{
 ((java.sql.Statement)link.createStatement()).executeUpdate(sql);
}catch( java.sql.SQLException e){
    popup(e.getLocalizedMessage()+"\n\n A connection will be attempted again","Connection error",2);
   try{
       link = dbcon(l,u,p);
      ((java.sql.Statement)link.createStatement()).executeUpdate(sql);

   }
   catch( java.sql.SQLException em){
       popup(em.getLocalizedMessage()+"\n\nReconnection failed! Program will exit.","Reconnect failed!",2);
       System.exit(0);

   }
}
}
public java.sql.ResultSet tableList(){
     try{
         return (link.getMetaData()).getTables(null, null, null, new String [] {"TABLE"});
}catch( java.sql.SQLException e){
    popup(e.getLocalizedMessage()+"\n\n A connection will be attempted again","Connection error",2);
    try{
       link = dbcon(l,u,p);
       return (link.getMetaData()).getTables(null, null, null, new String [] {"TABLE"});

   }
   catch( java.sql.SQLException em){
       popup(em.getLocalizedMessage()+"\n\nReconnection failed! Program will exit.","Reconnect failed!",2);
       System.exit(0);

   }
}
       return null;
}
}