1. To introduce servlet.jar in Application with servlet
2. Then you have to be in the .java file
import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpServlet; import javax.servlet.ServletException; import java.io.IOException; import java.io.PrintWriter; // This IMPORT can be introduced depending on the situation
3. Introduce several common methods in the servlet
a) Protected void service (httpservervetrequest req, httpservletResponse res) throws servletexception, ioException {}
If it is OverWrite, you may not call DOXXXMETHOD.
b) Protected void doget (httpservervetrequest req, httpservletResponse res) throws servletexception, ioException {}
Features 1: Safe and Idempotent. 2: Only Ascii (Text) Data Can Be Sent To Server with Get Method. 3: Easy to Bookmarks.
Main role: Get data, not change data
c) protected void dopost (httpservervetrequest req, httpservletResponse res) throws servletexception, oException {}
Features 1: NOT SAFE AND IDEMPOTENT. 2DISALLOW BOOKMARKS.
Main role: transmit Form Data, large quantity of data, often used in BBS, etc., can change data storage
There are some things to talk about next time.
