Spring Leaning: Servlet and Controller

Controller is essentially the same as a Servlet in Java Web development but under MVC framework. What a controller/servlet does is

• Receive user Requests
• Control service dispatch
• Send the request and code to Service layer.

High-Level flow of Servlet

Create a Servlet

1. create a Servlet

public class MyServlet extends HttpServlet {

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		//ServletOutputStream outputStream = resp.getOutputStream();
		PrintWriter writer = resp.getWriter();
		writer.print("Hello,Serlvet");
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		doGet(req, resp);
	}
}
								

Step 2: Register Servlet mapping

 < !--register Servlet-->
 < servlet>
	 < servlet-name>myServlet
	 < servlet-class>com.siyu.sevlet.MyServlet
 < /servlet>
 < !--servlet request path-->
 < servlet-mapping>
	 < servlet-name>myServlet
	 < url-pattern>/siyu
 < /servlet-mapping>