Start Simple java code for validating user in servlets

Simple java code for validating user in servlets

In this tutorial, we will validate data with a simple custom validation filter.

When the user fills out the form correctly the servlet returns a page that says "Welcome to my store Mr or Ms (depending on the gender button) and their first and last name. What I can't get to work is a try-catch block that will alert the user if they've missed one of the name fields or didn't check a gender radio button.

Is try-catch the way to go in this case or should I be using an if loop? Servlet Exception; import javax.servlet.annotation.

So, that is good practice for development and you are using MVC architect for development.

Then don't use HTML code in your Servlet make one separate jsp which contains basically your view part.

Even the service() method is non-abstract and infact with Http Servlet, the service() method can be replaced by the methods do Get() or do Post(). The above code works fine even if Generic Servlet is extended instead of Http Servlet. public void service(Http Servlet Request req, Http Servlet Response res) throws Servlet Exception, IOException service() method is a callback method called automatically when the container loads the servlet for execution when the client request comes.

The method takes two parameters – an object of interface Http Servlet Request and an object of interface Http Servlet Response and let us see what these interfaces meant to servlet.

The better approach is extending Generic Servlet (like Window Adapter to close the frame) which contains only one abstract method service().

It is enough to the programmer to override only this method. Generic Servlet was used by the programmers when HTTP protocol was not standardized for the Web.

From the servlet make one requestdispatcher object and call forward method which pass your request to jsp and display it. Our Simple Java class which contains variable declaration and getter and setter method with no argument constructor that is our POJO class.

Generally MVC model flow like Jsp -- Hi, POJO means Plain Old Java Object. Hi Nitin, If you want to suggestion for business logic then use same way as Ankit Garg says.

Filters can be used for various tasks such as authentication, logging, data compression, image conversion, or encryption.