Spring MVC controller receives the request value and the controller jumps and passes the value

Spring receives request parameters:

1, using HttpServletRequest to get Java code @RequestMapping ("/login.do") public String Login (HttpServletRequest request) {string name = Request.getpa Rameter ("name") String pass = Request.getparameter ("Pass")}

2,spring automatically injects form parameters into method parameters, and the Name property of the form remains the same.                                   As with Struts2 Java code @RequestMapping ("/login") public String Login (HttpServletRequest request,      String name, @RequestParam ("pass") string password)//The form attribute is pass, and the variable password receives {log.info (name); Log.info (password)}

3, automatically inject bean properties

Java code <form action= "Login" > User name: <input name= "name"/> Password: <input name= "pass"/> <input type= "su     Bmit "value=" "Login" > </form>//Package User-Class public class user{private String name;   Private String Pass; }

Java code @RequestMapping ("/login") public String login (user user) {Log.info (User.getname ());   Log.info (User.getpass ()); }

 

to pass a value to a page:

when the controller component is processed, the value is passed to the JSP page,

1, use HttpServletRequest and Session and then setattribute (), just like in a servlet

2, using the Modelandview object

3, using the Modelmap object

4, using @modelattribute annotations

The model data will use HttpServletRequest's attribute to pass the value to Java code @RequestMapping ("/login") public in success.jsp       Modelandview Login (String name,string pass) {User user = Userservice.login (name,pwd);       map<string,object> data = new hashmap<string,object> ();       Data.put ("user", user);   return new Modelandview ("Success", data); }

examples of using the Modelmap parameter object:

The modelmap data is used to transfer values from HttpServletRequest attribute to Java code in success.jsp @RequestMapping ("/login.do") public       String Login (String name,string Pass, Modelmap model) {User user = Userservice.login (name,pwd);       Model.addattribute ("user", user);       Model.put ("name", name);   Return "Success"; }

using the @modelattribute sample

used on the parameter part of the controller method or the Bean property method

@ModelAttribute data will be attribute to success.jsp using HttpServletRequest.

What is the difference between the Modelmap object's Addattribute,put two methods is that AddAttribute is not allowed to add a null value key,put is allowed
Java code @RequestMapping ("/login.do") public String Login (@ModelAttribute ("user") user user) {//todo return "   Success ";   } @ModelAttribute ("name") public String GetName () {return name; }

Session Storage:

can take advantage of Httpservletreequest's GetSession () method