What will happen if Get request will be used to call servlet with Post method ?

Given following form :

<form action="register.do">

    <input type="text" name="Name">

    <input type="submit" value="Save">

</form>

and a servlet code : 

public class RegisterServlet extends HttpServlet {

   public void doPost(HttpServletRequest req, HttpServletResponse res) {

      // registration logic goes here

      return;

  }

}

Answer

Here, The registration fails because, above servlet don't have doGet() method.