When the first request comes to this jsp, its simply redirect to the request to userRegistration.htm
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<% response.sendRedirect("userRegistration.htm"); %>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<servlet>
<servlet-name>dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dispatcher</servlet-name>
<url-pattern>*.htm</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
In the above web.xml file we have declared the url-pattern is *.htm, so it checks any request having *.htm, if any request having *.htm then it checks the corresponding servlet class, In our case its DispatcherServlet. Then Container looks the servlet name declared in web.xml accordingly it invokes the (servlet name in web.xml)-serlvet.xml file. In our case its dispatcher-servlet.xml file
dispatcher-servlet.xml
In the above web.xml file we have declared the servlet name as dispatcher, so our spring config file name should be dispatcher-servlet.xml only
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver"
p:prefix="/" p:suffix=".jsp" />
<bean name="/userRegistration.htm" class="com.UserController"
p:formView="userForm" p:successView="userSuccess" />
</beans>
As you can see, we use "p" namespace here. The "p" namespace is simple and easy to use. Using "p" namespace the properties can be supplied using attributes, rather than elements.
For injecting the simple types we use property name in the "p" namespace and for injecting references we add "-ref" suffix to it. For example we use p:formView for injecting the form view property andp:userService-ref for injecting the user service.
Our request having the /userRegistration.htm, So it invokes the UserContrller. before that it checks the formView, Here it is userForm then it invokes the userForm.jsp first.
userForm.jsp
pageEncoding="ISO-8859-1"%>
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Registration Page</title>
</head>
<body>
<form:form method="POST" commandName="user">
<table>
<tr>
<td>User Name :</td>
<td><form:input path="name" /></td>
</tr>
<tr>
<td>Password :</td>
<td><form:password path="password" /></td>
</tr>
<tr>
<td>Gender :</td>
<td><form:radiobutton path="gender" value="M" />
<form:radiobutton path="gender" value="F" /></td>
</tr>
<tr>
<td>About you :</td>
<td><form:textarea path="aboutYou" /></td>
</tr>
<tr>
<td colspan="2"><input type="submit"></td>
</tr>
</table>
</form:form>
</body>
</html>
Here the path attribute is used to bind the form fields to the domain object. Here we use the HTTP POST method to submit the form. Inorder to bind the form fields to the domain object successfully the command object should be set to the same name in the jsp page and the controller class. To set the command object name in the jsp page, use the commandName attribute of the form tag.
UserController.java
package com;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.SimpleFormController;
public class UserController extends SimpleFormController {
public UserController() {
setCommandClass(User.class);
setCommandName("user");
}
protected ModelAndView onSubmit(Object command) throws Exception {
User user = (User) command;
return new ModelAndView("userSuccess","user",user);
}
}
Here we extend the UserController from SimpleFormController, this makes the controller class capable of handling forms. Usually a form will be associated with a particular domain object, in our case it is the Userclass. In Spring this domain object is called command object by default. To refer the command object in the jsp page you need to set the command class using the setCommandClass() method in the constructor. Let say the User class has a name property, and to refer this in the jsp page you will use "command.name". You can also change this name by using the setCommandName() method. Here we set the name to user, so to access the user name in the jsp page we use "user.name".
You need to have a method to handle the form when the form is submitted, here the onSubmit()method is used for this purpose. The onSubmit() method has access to the command object, we first typecast the command object to User (our domain object) and then to register the user we call the add() method of the service class and finally return the ModelandView object.
All the forms field values will be submitted as Strings to the form controller. Spring has several pre registered property editors to convert the String values to common data types. Incase you have a custom data type you need to create custom property editors to handle them.
User.java
package com;
public class User {
private String name;
private String password;
private String gender;
private String aboutYou;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public String getAboutYou() {
return aboutYou;
}
public void setAboutYou(String aboutYou) {
this.aboutYou = aboutYou;
}
}
userSuccess.jsp
we have declared the successView in the dispatcher-servlet.xml as userSuccess, So it invokes the userSuccess.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Success Page</title>
</head>
<body>
User Details
<hr>
User Name : ${user.name} <br/>
Gender : ${user.gender} <br/>
About You : ${user.aboutYou} <br/>
</body>
</html>
