3 Validators in Struts2-Spring-Hibernate

3 Validators in Struts2-Spring-Hibernate

In this article, I will introduce 3 ways in writing validators in Struts2-Spring-Hibernate application.

First of all, create package com.ssh.bean and create a bean named 'User' under this package:
User.java

 1  package  com.ssh.bean;
 2 
 3  public   class  User {
 4       private   long  id;
 5       private  String username;
 6       private  String password;
 7       private  String firstname;
 8       private  String lastname;
 9       private  String email;
10       private  String street;
11       private  String city;
12       private  String state;
13       private  String zip;
14      
15       public   long  getId() {
16           return  id;
17      }
18       public   void  setId( long  id) {
19           this .id  =  id;
20      }
21       public  String getUsername() {
22           return  username;
23      }
24       public   void  setUsername(String username) {
25           this .username  =  username;
26      }
27       public  String getPassword() {
28           return  password;
29      }
30       public   void  setPassword(String password) {
31           this .password  =  password;
32      }
33       public  String getFirstname() {
34           return  firstname;
35      }
36       public   void  setFirstname(String firstname) {
37           this .firstname  =  firstname;
38      }
39       public  String getLastname() {
40           return  lastname;
41      }
42       public   void  setLastname(String lastname) {
43           this .lastname  =  lastname;
44      }
45       public  String getEmail() {
46           return  email;
47      }
48       public   void  setEmail(String email) {
49           this .email  =  email;
50      }
51       public  String getStreet() {
52           return  street;
53      }
54       public   void  setStreet(String street) {
55           this .street  =  street;
56      }
57       public  String getCity() {
58           return  city;
59      }
60       public   void  setCity(String city) {
61           this .city  =  city;
62      }
63       public  String getState() {
64           return  state;
65      }
66       public   void  setState(String state) {
67           this .state  =  state;
68      }
69       public  String getZip() {
70           return  zip;
71      }
72       public   void  setZip(String zip) {
73           this .zip  =  zip;
74      }
75  }

Under the same package, create User.hbm.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE hibernate-mapping PUBLIC
 3      "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
 4      "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd" >
 5  < hibernate-mapping >
 6       < class  name ="com.ssh.bean.User"  table ="user" >
 7           < id  name ="id"  type ="java.lang.Long"  column ="id" >
 8               < generator  class ="increment" ></ generator >
 9           </ id >
10           < property  name ="username"  type ="string"  column ="username"  length ="200" ></ property >
11           < property  name ="password"  type ="string"  column ="password"  length ="200" ></ property >
12           < property  name ="firstname"  type ="string"  column ="firstname"  length ="200" ></ property >
13           < property  name ="lastname"  type ="string"  column ="lastname"  length ="200" ></ property >
14           < property  name ="email"  type ="string"  column ="email"  length ="200" ></ property >
15           < property  name ="street"  type ="string"  column ="street"  length ="200" ></ property >
16           < property  name ="city"  type ="string"  column ="city"  length ="200" ></ property >
17           < property  name ="state"  type ="string"  column ="state"  length ="50" ></ property >
18           < property  name ="zip"  type ="string"  column ="zip"  length ="50" ></ property >
19       </ class >
20  </ hibernate-mapping >

Create hibernate.cfg.xml directory under 'src':

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE hibernate-configuration PUBLIC
 3      "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
 4      "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd" >
 5 
 6  < hibernate-configuration >
 7       < session-factory >
 8           < property  name ="hibernate.connection.url" > jdbc:mysql://localhost:3306/blogjava </ property >
 9           < property  name ="hibernate.connection.driver_class" > com.mysql.jdbc.Driver </ property >
10           < property  name ="hibernate.connection.username" > root </ property >
11           < property  name ="hibernate.connection.password" > 123456789 </ property >
12           < property  name ="hibernate.dialect" > org.hibernate.dialect.MySQLDialect </ property >
13           < property  name ="hibernate.show_sql" > true </ property >
14          
15           < mapping  resource ="com/ssh/bean/User.hbm.xml" />
16       </ session-factory >
17  </ hibernate-configuration >

In this configuration file, I am using MySql and the database schema is blogjava.
My database admin username is root and password is 123456789. Change them if it is needed according to your database.

Then, create package com.ssh.test and create ExportDB.java under this package:

 1  package  com.ssh.test;
 2 
 3  import  org.hibernate.cfg.Configuration;
 4  import  org.hibernate.tool.hbm2ddl.SchemaExport;
 5 
 6  public   class  ExportDB {
 7       public   static   void  main(String[] args){
 8          Configuration cfg  =   new  Configuration().configure();
 9          SchemaExport export  =   new  SchemaExport(cfg);
10          export.create( true ,  true );
11      }
12  }

Run this class and a table named 'user' is created under 'blogjava'. There are 2 lines printed out in console:
drop table if exists user
create table user (id bigint not null, username varchar(200), password varchar(200), firstname varchar(200), lastname varchar(200), email varchar(200), street varchar(200), city varchar(200), state varchar(50), zip varchar(50), primary key (id))

The reason not using create SQL directory in MySql but using hibernate technique is it can better realize the OO idea.
Check the table 'user' under command line:


Now we create register.jsp under WebContent directly, if you are using MyEclipse, it's probably 'WebRoot'.

 1  <% @ page language = " java "  contentType = " text/html; charset=UTF-8 "
 2      pageEncoding = " UTF-8 " %>
 3  <% @ taglib prefix = " s "  uri = " /struts-tags " %>
 4  <! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
 5  < html >
 6  < head >
 7  < meta  http-equiv ="Content-Type"  content ="text/html; charset=UTF-8" >
 8  < title > New User Registration </ title >
 9  </ head >
10  < body >
11  < s:form action ="register"  theme ="simple" >
12       < table  style ="border-collapse: collapse"  align ="left"
13          bordercolor =#3f8805  cellspacing =0  cellpadding =0  width ="20%"  border =1 >
14           < tr >
15               < td > username </ td >
16               < td >< s:textfield  name ="user.username" ></ s:textfield ></ td >
17           </ tr >
18           < tr >
19               < td > password </ td >
20               < td >< s:password  name ="user.password" ></ s:password ></ td >
21           </ tr >
22           < tr >
23               < td > re-password </ td >
24               < td >< s:password  name ="repassword" ></ s:password ></ td >
25           </ tr >
26           < tr >
27               < td > firstname </ td >
28               < td >< s:textfield  name ="user.firstname" ></ s:textfield ></ td >
29           </ tr >
30           < tr >
31               < td > lastname </ td >
32               < td >< s:textfield  name ="user.lastname" ></ s:textfield ></ td >
33           </ tr >
34           < tr >
35               < td > email </ td >
36               < td >< s:textfield  name ="user.email" ></ s:textfield ></ td >
37           </ tr >
38           < tr >
39               < td > street address </ td >
40               < td >< s:textfield  name ="user.street" ></ s:textfield ></ td >
41           </ tr >
42           < tr >
43               < td > city </ td >
44               < td >< s:textfield  name ="user.city" ></ s:textfield ></ td >
45           </ tr >
46           < tr >
47               < td > state </ td >
48               < td >< s:textfield  name ="user.state" ></ s:textfield ></ td >
49           </ tr >
50           < tr >
51               < td > zip code </ td >
52               < td >< s:textfield  name ="user.zip" ></ s:textfield ></ td >
53           </ tr >
54           < tr >
55               < td ></ td >
56               < td >< s:submit ></ s:submit >   < s:reset ></ s:reset ></ td >
57           </ tr >
58       </ table >
59  </ s:form >
60  </ body >
61  </ html >

In this case, I don't use css because it's only a demo of struts2 validator.
Start up Tomcat server and open web browser with "http://localhost:8080/loginbystruts/register.jsp"

Actually, because of validator, register.jsp will be changed a little by adding field error.

Now it's time to create struts.xml under 'src' directly:

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE struts PUBLIC
 3          "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
 4          "http://struts.apache.org/dtds/struts-2.0.dtd" >
 5  < struts >
 6       < package  name ="sshlogin"  extends ="struts-default" >
 7           < action  name ="login"  class ="loginAction"  method ="login" >
 8               < result  name ="success" > /user.jsp </ result >
 9               < result  name ="input" > /login.jsp </ result >
10           </ action >
11          
12           < action  name ="register"  class ="registerAction"  method ="register" >
13               < result  name ="success" > /user.jsp </ result >
14               < result  name ="input" > /register.jsp </ result >
15           </ action >
16       </ package >
17  </ struts >

Create Spring MVC: DAO and Service interface as well as their implementation classes like following struture:


UserDao.java:

 1  package  com.ssh.dao;
 2 
 3  import  com.ssh.bean.User;
 4  import  java.util.List;
 5  public   interface  UserDao {
 6       public   void  save(User user);
 7       public   void  remove(User user);
 8       public  User findUserById( long  id);
 9       public  List < User >  findAll();
10       public   void  update(User user);
11  }

UserDaoImpl.java

 1  package  com.ssh.dao.impl;
 2 
 3  import  java.util.List;
 4  import  org.springframework.orm.hibernate3.support.HibernateDaoSupport;
 5  import  com.ssh.bean.User;
 6  import  com.ssh.dao.UserDao;
 7 
 8  public   class  UserDaoImpl  extends  HibernateDaoSupport  implements  UserDao {
 9      @SuppressWarnings( " unchecked " )
10      @Override
11       public  List < User >  findAll() {
12           //  TODO Auto-generated method stub
13          String hql  =   " from User user order by user.id desc " ;
14           return  (List < User > )  this .getHibernateTemplate().find(hql);
15      }
16 
17      @Override
18       public  User findUserById( long  id) {
19           //  TODO Auto-generated method stub
20          User user  =  (User)  this .getHibernateTemplate().get(User. class , id);
21           return  user;
22      }
23 
24      @Override
25       public   void  remove(User user) {
26           //  TODO Auto-generated method stub
27           this .getHibernateTemplate().delete(user);
28      }
29 
30      @Override
31       public   void  save(User user) {
32           //  TODO Auto-generated method stub
33           this .getHibernateTemplate().save(user);
34      }
35 
36      @Override
37       public   void  update(User user) {
38           //  TODO Auto-generated method stub
39           this .getHibernateTemplate().update(user);
40      }
41  }

UserService.java

 1  package  com.ssh.service;
 2 
 3  import  java.util.List;
 4  import  com.ssh.bean.User;
 5 
 6  public   interface  UserService {
 7       public   void  save(User user);
 8       public   void  remove(User user);
 9       public  User findUserById( long  id);
10       public  List < User >  findAll();
11       public   void  update(User user);
12  }
13 

UserServiceImpl.java

 1  package  com.ssh.service.impl;
 2 
 3  import  java.util.List;
 4  import  com.ssh.bean.User;
 5  import  com.ssh.dao.UserDao;
 6  import  com.ssh.service.UserService;
 7 
 8  public   class  UserServiceImpl  implements  UserService {
 9      
10       private  UserDao userDao;
11      
12       public  UserDao getUserDao() {
13           return  userDao;
14      }
15 
16       public   void  setUserDao(UserDao userDao) {
17           this .userDao  =  userDao;
18      }
19 
20      @Override
21       public  List < User >  findAll() {
22           //  TODO Auto-generated method stub
23           return   this .userDao.findAll();
24      }
25 
26      @Override
27       public  User findUserById( long  id) {
28           //  TODO Auto-generated method stub
29           return   this .userDao.findUserById(id);
30      }
31 
32      @Override
33       public   void  remove(User user) {
34           //  TODO Auto-generated method stub
35           this .userDao.remove(user);
36      }
37 
38      @Override
39       public   void  save(User user) {
40           //  TODO Auto-generated method stub
41           this .userDao.save(user);
42      }
43 
44      @Override
45       public   void  update(User user) {
46           //  TODO Auto-generated method stub
47           this .userDao.update(user);
48      }
49 
50  }
51 

Create applicationContext.xml under 'WebContent/WEB-INF'

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  < beans  xmlns ="http://www.springframework.org/schema/beans"
 3         xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
 4         xsi:schemaLocation ="
 5  http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd" >
 6 
 7  <!--  <bean/> definitions here  -->
 8       < bean  id ="dataSource"  class ="org.apache.commons.dbcp.BasicDataSource"  destroy-method ="close" >
 9           < property  name ="driverClassName"  value ="com.mysql.jdbc.Driver" ></ property >
10           < property  name ="url"  value ="jdbc:mysql://localhost:3306/blogjava" ></ property >
11           < property  name ="username"  value ="root" ></ property >
12           < property  name ="password"  value ="112358" ></ property >
13           < property  name ="maxActive"  value ="100" ></ property >
14           < property  name ="maxIdle"  value ="30" ></ property >
15           < property  name ="maxWait"  value ="500" ></ property >
16           < property  name ="defaultAutoCommit"  value ="true" ></ property >
17       </ bean >
18       < bean  id ="sessionFactory"  class ="org.springframework.orm.hibernate3.LocalSessionFactoryBean" >
19           < property  name ="dataSource"  ref ="dataSource" ></ property >
20           < property  name ="hibernateProperties" >
21               < props >
22                   < prop  key ="hibernate.dialect" > org.hibernate.dialect.MySQLDialect </ prop >
23                   < prop  key ="show_sql" > true </ prop >
24               </ props >
25           </ property >
26           < property  name ="mappingResources" >
27               < list >
28                   < value > com/ssh/bean/User.hbm.xml </ value >
29               </ list >
30           </ property >
31       </ bean >
32      
33       < bean  id ="userDao"  class ="com.ssh.dao.impl.UserDaoImpl"  scope ="singleton" >
34           < property  name ="sessionFactory" >
35               < ref  bean ="sessionFactory" />
36           </ property >
37       </ bean >
38      
39       < bean  id ="userService"  class ="com.ssh.service.impl.UserServiceImpl" >
40           < property  name ="userDao" >
41               < ref  bean ="userDao" />
42           </ property >
43       </ bean >
44      
45       < bean  id ="loginAction"  class ="com.ssh.action.LoginAction"  scope ="prototype" >
46           < property  name ="userService" >
47               < ref  bean ="userService" />
48           </ property >
49       </ bean >
50      
51       < bean  id ="registerAction"  class ="com.ssh.action.RegisterAction"  scope ="prototype" >
52           < property  name ="userService" >
53               < ref  bean ="userService" ></ ref >
54           </ property >
55       </ bean >
56  </ beans >

Configure web.xml in the same directory as applicationContext.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  < web-app  xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
 3      xmlns ="http://java.sun.com/xml/ns/javaee"
 4      xmlns:web ="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 5      xsi:schemaLocation ="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 6      id ="WebApp_ID"  version ="2.5" >
 7       < display-name > loginbystruts </ display-name >
 8       < filter >
 9           < filter-name > struts2 </ filter-name >
10           < filter-class >
11              org.apache.struts2.dispatcher.FilterDispatcher
12           </ filter-class >
13       </ filter >
14       < filter-mapping >
15           < filter-name > struts2 </ filter-name >
16           < url-pattern > /* </ url-pattern >
17       </ filter-mapping >
18       < listener >
19           < listener-class >
20              org.springframework.web.context.ContextLoaderListener
21           </ listener-class >
22       </ listener >
23  </ web-app >

Create package com.ssh.action and then create RegisterAction.java and LoginAction.java
RegisterAction.java

 1  package  com.ssh.action;
 2 
 3  import  com.opensymphony.xwork2.ActionSupport;
 4  import  com.ssh.bean.User;
 5  import  com.ssh.service.UserService;
 6 
 7  public   class  RegisterAction  extends  ActionSupport {
 8       private  UserService userService;
 9       private  User user;
10       private  String repassword;
11       public  UserService getUserService() {
12           return  userService;
13      }
14       public   void  setUserService(UserService userService) {
15           this .userService  =  userService;
16      }
17       public  User getUser() {
18           return  user;
19      }
20       public   void  setUser(User user) {
21           this .user  =  user;
22      }
23       public  String getRepassword() {
24           return  repassword;
25      }
26       public   void  setRepassword(String repassword) {
27           this .repassword  =  repassword;
28      }
29      
30       public  String register(){
31           this .userService.save(user);
32           return  SUCCESS;
33      }
34      @Override
35       public   void  validate() {
36           //  TODO Auto-generated method stub
37           if ( null   ==   this .user.getUsername()  ||   "" .equals( this .user.getUsername()))
38               this .addFieldError( " username " ,  " username is null " );
39           if ( null   ==   this .user.getPassword()  ||   "" .equals( this .user.getPassword()))
40               this .addFieldError( " password " ,  " password is null " );
41           if ( null   ==   this .repassword  ||   "" .equals( this .repassword))
42               this .addFieldError( " repassword " ,  " confirm your password " );
43           if ( null   ==   this .user.getEmail()  ||   "" .equals( this .user.getEmail()))
44               this .addFieldError( " email " ,  " email is null " );
45          
46      }
47  }

LoginAction.java

 1  package  com.ssh.action;
 2 
 3  import  java.util.List;
 4  import  com.opensymphony.xwork2.ActionSupport;
 5  import  com.ssh.bean.User;
 6  import  com.ssh.service.UserService;
 7 
 8  public   class  LoginAction  extends  ActionSupport {
 9       private  UserService userService;
10       private  User user;
11       public   void  setUserService(UserService userService) {
12           this .userService  =  userService;
13      }
14      
15       public  User getUser() {
16           return  user;
17      }
18 
19       public   void  setUser(User user) {
20           this .user  =  user;
21      }
22 
23       public  String login(){
24          List < User >  users  =   this .userService.findAll();
25           if (users  ==   null   ||  users.isEmpty())
26               return  INPUT;
27           for ( int  i = 0 ; i < users.size(); i ++ ){
28              User u  =  users.get(i);
29               if (u.getUsername().equals(user.getUsername())){
30                   if (u.getPassword().equals(user.getPassword()))
31                       return  SUCCESS;
32                   else
33                       continue ;
34              } else
35                   continue ;
36          }
37           return  INPUT;
38      }
39 
40      @Override
41       public   void  validate() {
42           //  TODO Auto-generated method stub
43           if ( null   ==   this .user.getUsername()  ||   "" .equals( this .user.getUsername()))
44               this .addFieldError( " username " ,  " username is null " );
45           if ( null   ==   this .user.getPassword()  ||   "" .equals( this .user.getPassword()))
46               this .addFieldError( " password " ,  " password is null " );
47      }
48  }
49 

 
Edit register.jsp again according to the previous one:

 1  <% @ page language = " java "  contentType = " text/html; charset=UTF-8 "
 2      pageEncoding = " UTF-8 " %>
 3  <% @ taglib prefix = " s "  uri = " /struts-tags " %>
 4  <! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
 5  < html >
 6  < head >
 7  < meta  http-equiv ="Content-Type"  content ="text/html; charset=UTF-8" >
 8  < title > New User Registration </ title >
 9  </ head >
10  < body >
11  < s:form  action ="register"  theme ="simple" >
12       < table  style ="border-collapse: collapse"  align ="left"
13          bordercolor =#3f8805  cellspacing =0  cellpadding =0  width ="20%"  border =1 >
14           < tr >
15               < td > username </ td >
16               < td >
17                   < s:fielderror  cssStyle ="color:red" >
18                       < s:param > username </ s:param >
19                   </ s:fielderror >
20                   < s:textfield  name ="user.username" ></ s:textfield >
21               </ td >
22           </ tr >
23           < tr >
24               < td > password </ td >
25               < td >
26                   < s:fielderror  cssStyle ="color:red" >
27                       < s:param > password </ s:param >
28                   </ s:fielderror >
29                   < s:password  name ="user.password" ></ s:password >
30               </ td >
31           </ tr >
32           < tr >
33               < td > re-password </ td >
34               < td >
35                   < s:fielderror  cssStyle ="color:red" >
36                       < s:param > repassword </ s:param >
37                   </ s:fielderror >
38                   < s:password  name ="repassword" ></ s:password >
39               </ td >
40           </ tr >
41           < tr >
42               < td > firstname </ td >
43               < td >< s:textfield  name ="user.firstname" ></ s:textfield ></ td >
44           </ tr >
45           < tr >
46               < td > lastname </ td >
47               < td >< s:textfield  name ="user.lastname" ></ s:textfield ></ td >
48           </ tr >
49           < tr >
50               < td > email </ td >
51               < td >
52                   < s:fielderror  cssStyle ="color:red" >
53                       < s:param > email </ s:param >
54                   </ s:fielderror >
55                   < s:textfield  name ="user.email" ></ s:textfield >
56               </ td >
57           </ tr >
58           < tr >
59               < td > street address </ td >
60               < td >< s:textfield  name ="user.street" ></ s:textfield ></ td >
61           </ tr >
62           < tr >
63               < td > city </ td >
64               < td >< s:textfield  name ="user.city" ></ s:textfield ></ td >
65           </ tr >
66           < tr >
67               < td > state </ td >
68               < td >< s:textfield  name ="user.state" ></ s:textfield ></ td >
69           </ tr >
70           < tr >
71               < td > zip code </ td >
72               < td >< s:textfield  name ="user.zip" ></ s:textfield ></ td >
73           </ tr >
74           < tr >
75               < td ></ td >
76               < td >< s:submit ></ s:submit >   < s:reset ></ s:reset ></ td >
77           </ tr >
78       </ table >
79  </ s:form >
80  </ body >
81  </ html >

login.jsp

 1  <% @ page language = " java "  contentType = " text/html; charset=UTF-8 "
 2      pageEncoding = " UTF-8 " %>
 3  <% @ taglib prefix = " s "  uri = " /struts-tags " %>
 4  <! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
 5  < html >
 6  < head >
 7  < meta  http-equiv ="Content-Type"  content ="text/html; charset=UTF-8" >
 8  < title > Login </ title >
 9  </ head >
10  < body >
11  <% --  action = " login "  actually can work  with  this  error .  -- %>
12  < s:form  action ="login"  theme ="simple" >
13       < table  style ="border-collapse: collapse"  align ="left"
14          bordercolor =#3f8805  cellspacing =0  cellpadding =0  width ="20%"  border =1 >
15           < tr >
16               < td > username </ td >
17               < td >
18                   < s:fielderror  cssStyle ="color:red" >
19                       < s:param > username </ s:param >
20                   </ s:fielderror >
21                   < s:textfield  name ="user.username" ></ s:textfield >
22               </ td >
23           </ tr >
24          
25           < tr >
26               < td > password </ td >
27               < td >
28                   < s:fielderror  cssStyle ="color:red" >
29                       < s:param > password </ s:param >
30                   </ s:fielderror >
31                   < s:password  name ="user.password" ></ s:password >
32               </ td >
33           </ tr >
34           < tr >
35               < td ></ td >
36               < td >
37                   < s:submit ></ s:submit >
38                   < s:reset ></ s:reset >
39               </ td >
40           </ tr >
41       </ table >
42  </ s:form >
43  </ body >
44  </ html >

Start Tomcat server and open web browser with http://localhost:8080/loginbystruts/register.jsp


If click submit without type in any information:



Now test address "http://localhost:8080/loginbystruts/login.jsp"


Without any information, it will be:




Now, let me introduce another method implementing struts2 validator based on XML without re-writing validate() method in LoginAction.java and RegisterAction.java.

First, annotate validate in both LoginAction.java and RegisterAction.java
LoginAction.java

 1  package  com.ssh.action;
 2 
 3  import  java.util.List;
 4  import  com.opensymphony.xwork2.ActionSupport;
 5  import  com.ssh.bean.User;
 6  import  com.ssh.service.UserService;
 7 
 8  public   class  LoginAction  extends  ActionSupport {
 9       private  UserService userService;
10       private  User user;
11       public   void  setUserService(UserService userService) {
12           this .userService  =  userService;
13      }
14      
15       public  User getUser() {
16           return  user;
17      }
18 
19       public   void  setUser(User user) {
20           this .user  =  user;
21      }
22 
23       public  String login(){
24          List < User >  users  =   this .userService.findAll();
25           if (users  ==   null   ||  users.isEmpty())
26               return  INPUT;
27           for ( int  i = 0 ; i < users.size(); i ++ ){
28              User u  =  users.get(i);
29               if (u.getUsername().equals(user.getUsername())){
30                   if (u.getPassword().equals(user.getPassword()))
31                       return  SUCCESS;
32                   else
33                       continue ;
34              } else
35                   continue ;
36          }
37           return  INPUT;
38      }
39       /*
40      @Override
41      public void validate() {
42          // TODO Auto-generated method stub
43          if(null == this.user.getUsername() || "".equals(this.user.getUsername()))
44              this.addFieldError("username", "username is null");
45          if(null == this.user.getPassword() || "".equals(this.user.getPassword()))
46              this.addFieldError("password", "password is null");
47      }
48       */
49  }
50 

RegisterAction.java

 1  package  com.ssh.action;
 2 
 3  import  com.opensymphony.xwork2.ActionSupport;
 4  import  com.ssh.bean.User;
 5  import  com.ssh.service.UserService;
 6 
 7  public   class  RegisterAction  extends  ActionSupport {
 8       private  UserService userService;
 9       private  User user;
10       private  String repassword;
11       public  UserService getUserService() {
12           return  userService;
13      }
14       public   void  setUserService(UserService userService) {
15           this .userService  =  userService;
16      }
17       public  User getUser() {
18           return  user;
19      }
20       public   void  setUser(User user) {
21           this .user  =  user;
22      }
23       public  String getRepassword() {
24           return  repassword;
25      }
26       public   void  setRepassword(String repassword) {
27           this .repassword  =  repassword;
28      }
29      
30       public  String register(){
31           this .userService.save(user);
32           return  SUCCESS;
33      }
34       /*
35      @Override
36      public void validate() {
37          // TODO Auto-generated method stub
38          if(null == this.user.getUsername() || "".equals(this.user.getUsername()))
39              this.addFieldError("username", "username is null");
40          if(null == this.user.getPassword() || "".equals(this.user.getPassword()))
41              this.addFieldError("password", "password is null");
42          if(null == this.repassword || "".equals(this.repassword))
43              this.addFieldError("repassword", "confirm your password");
44          if(null == this.user.getEmail() || "".equals(this.user.getEmail()))
45              this.addFieldError("email", "email is null");
46          
47      }
48       */
49  }

Now new LoginAction-validation.xml and RegisterAction-validation.xml.

Here is the naming rules: ***-validation.xml, *** must be same as the name as the action, such as if you have UserAction.java, the validator xml name must be UserAction-validation.xml. Second, ***-validation.xml must be in the same package with its action class.
In this case, There are LoginAction-validation.xml and RegisterAction-validation.xml, and they stay with LoginAction.java and RegisterAction.java;


LoginAction-validation.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 
 3              "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd" >
 4 
 5  < validators >
 6       < field  name ="user.username" >
 7           < field-validator  type ="requiredstring" >
 8               < message > You must enter your username </ message >
 9           </ field-validator >
10       </ field >
11       < field  name ="user.password" >
12           < field-validator  type ="requiredstring" >
13               < message > You must enter your password </ message >
14           </ field-validator >
15       </ field >
16  </ validators >

RegisterAction-validation.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 
 3              "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd" >
 4 
 5  < validators >
 6       < field  name ="user.username" >
 7           < field-validator  type ="requiredstring" >
 8               < message > You must enter your username </ message >
 9           </ field-validator >
10       </ field >
11       < field  name ="user.password" >
12           < field-validator  type ="requiredstring" >
13               < message > You must enter your password </ message >
14           </ field-validator >
15       </ field >
16       < field  name ="repassword" >
17           < field-validator  type ="requiredstring" >
18               < message > You must confirm your password </ message >
19           </ field-validator >
20       </ field >
21       < field  name ="user.email" >
22           < field-validator  type ="requiredstring" >
23               < message > You must enter your email address </ message >
24           </ field-validator >
25       </ field >
26  </ validators >

Then, I need to change login.jsp and register.jsp according to the field name. It requires the <s:param>**</s:param> in <s:fielderror> have the same content as <field name="***">, now it is user.username rather than username in the previous validation method. 'repassword' stays out of change because it's only a base variable.

login.jsp

 1  <% @ page language = " java "  contentType = " text/html; charset=UTF-8 "
 2      pageEncoding = " UTF-8 " %>
 3  <% @ taglib prefix = " s "  uri = " /struts-tags " %>
 4  <! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
 5  < html >
 6  < head >
 7  < meta  http-equiv ="Content-Type"  content ="text/html; charset=UTF-8" >
 8  < title > Login </ title >
 9  </ head >
10  < body >
11  <% --  action = " login "  actually can work  with  this  error .  -- %>
12  < s:form  action ="login"  theme ="simple" >
13       < table  style ="border-collapse: collapse"  align ="left"
14          bordercolor =#3f8805  cellspacing =0  cellpadding =0  width ="20%"  border =1 >
15           < tr >
16               < td > username </ td >
17               < td >
18                   < s:fielderror  cssStyle ="color:red" >
19                       < s:param > user.username </ s:param >
20                   </ s:fielderror >
21                   < s:textfield  name ="user.username" ></ s:textfield >
22               </ td >
23           </ tr >
24          
25           < tr >
26               < td > password </ td >
27               < td >
28                   < s:fielderror  cssStyle ="color:red" >
29                       < s:param > user.password </ s:param >
30                   </ s:fielderror >
31                   < s:password  name ="user.password" ></ s:password >
32               </ td >
33           </ tr >
34           < tr >
35               < td ></ td >
36               < td >
37                   < s:submit ></ s:submit >
38                   < s:reset ></ s:reset >
39               </ td >
40           </ tr >
41       </ table >
42  </ s:form >
43  </ body >
44  </ html >

register.jsp

 1  <% @ page language = " java "  contentType = " text/html; charset=UTF-8 "
 2      pageEncoding = " UTF-8 " %>
 3  <% @ taglib prefix = " s "  uri = " /struts-tags " %>
 4  <! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
 5  < html >
 6  < head >
 7  < meta  http-equiv ="Content-Type"  content ="text/html; charset=UTF-8" >
 8  < title > New User Registration </ title >
 9  </ head >
10  < body >
11  < s:form  action ="register"  theme ="simple" >
12       < table  style ="border-collapse: collapse"  align ="left"
13          bordercolor =#3f8805  cellspacing =0  cellpadding =0  width ="20%"  border =1 >
14           < tr >
15               < td > username </ td >
16               < td >
17                   < s:fielderror  cssStyle ="color:red" >
18                       < s:param > user.username </ s:param >
19                   </ s:fielderror >
20                   < s:textfield  name ="user.username" ></ s:textfield >
21               </ td >
22           </ tr >
23           < tr >
24               < td > password </ td >
25               < td >
26                   < s:fielderror  cssStyle ="color:red" >
27                       < s:param > user.password </ s:param >
28                   </ s:fielderror >
29                   < s:password  name ="user.password" ></ s:password >
30               </ td >
31           </ tr >
32           < tr >
33               < td > re-password </ td >
34               < td >
35                   < s:fielderror  cssStyle ="color:red" >
36                       < s:param > repassword </ s:param >
37                   </ s:fielderror >
38                   < s:password  name ="repassword" ></ s:password >
39               </ td >
40           </ tr >
41           < tr >
42               < td > firstname </ td >
43               < td >< s:textfield  name ="user.firstname" ></ s:textfield ></ td >
44           </ tr >
45           < tr >
46               < td > lastname </ td >
47               < td >< s:textfield  name ="user.lastname" ></ s:textfield ></ td >
48           </ tr >
49           < tr >
50               < td > email </ td >
51               < td >
52                   < s:fielderror  cssStyle ="color:red" >
53                       < s:param > user.email </ s:param >
54                   </ s:fielderror >
55                   < s:textfield  name ="user.email" ></ s:textfield >
56               </ td >
57           </ tr >
58           < tr >
59               < td > street address </ td >
60               < td >< s:textfield  name ="user.street" ></ s:textfield ></ td >
61           </ tr >
62           < tr >
63               < td > city </ td >
64               < td >< s:textfield  name ="user.city" ></ s:textfield ></ td >
65           </ tr >
66           < tr >
67               < td > state </ td >
68               < td >< s:textfield  name ="user.state" ></ s:textfield ></ td >
69           </ tr >
70           < tr >
71               < td > zip code </ td >
72               < td >< s:textfield  name ="user.zip" ></ s:textfield ></ td >
73           </ tr >
74           < tr >
75               < td ></ td >
76               < td >< s:submit ></ s:submit >   < s:reset ></ s:reset ></ td >
77           </ tr >
78       </ table >
79  </ s:form >
80  </ body >
81  </ html >

Now test again:





For better comparison, I change the error printou to "You must enter ....".

Now, let me introduce the third method of validator in struts2.

Using type="visitor" in validator.

First, annotate all the validators in previous method, and add new ones in RegisterAction-validation.xml and LoginAction-validation.xml

RegisterAction-validation.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 
 3              "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd" >
 4  <!--
 5  <validators>
 6      <field name="user.username">
 7          <field-validator type="requiredstring">
 8              <message>You must enter your username</message>
 9          </field-validator>
10      </field>
11      <field name="user.password">
12          <field-validator type="requiredstring">
13              <message>You must enter your password</message>
14          </field-validator>
15      </field>
16      <field name="repassword">
17          <field-validator type="requiredstring">
18              <message>You must confirm your password</message>
19          </field-validator>
20      </field>
21      <field name="user.email">
22          <field-validator type="requiredstring">
23              <message>You must enter your email address</message>
24          </field-validator>
25      </field>
26  </validators>
27  -->
28  < validators >
29       < field  name ="user" >   <!--   The corresponding action class must have user as a member variable -->
30           < field-validator  type ="visitor" >
31               < param  name ="context" > registercontext </ param >   <!--  must have User-registercontext-validation.xml in com.ssh.bean  -->
32               < param  name ="appendPrefix" > true </ param >
33               < message > Missing information,  </ message >
34           </ field-validator >
35       </ field >
36       < field  name ="repassword" >
37           < field-validator  type ="requiredstring" >
38               < message > You must confirm your password </ message >
39           </ field-validator >
40       </ field >
41  </ validators >

LoginAction-validation.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 
 3              "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd" >
 4  <!--
 5  <validators>
 6      <field name="user.username">
 7          <field-validator type="requiredstring">
 8              <message>You must enter your username</message>
 9          </field-validator>
10      </field>
11      <field name="user.password">
12          <field-validator type="requiredstring">
13              <message>You must enter your password</message>
14          </field-validator>
15      </field>
16  </validators>
17  -->
18  < validators >
19       < field  name ="user" >   <!--   The corresponding action class must have user as a member variable -->
20           < field-validator  type ="visitor" >
21               < param  name ="context" > logincontext </ param >   <!--  must have User-logincontext-validation.xml in com.ssh.bean  -->
22               < param  name ="appendPrefix" > true </ param >
23               < message > Missing information,  </ message >
24           </ field-validator >
25       </ field >
26  </ validators >

Now, under package com.ssh.bean, create User-registercontext-validation.xml and User-logincontenxt-validation.xml.

Notice: registercontext is the param name in RegiserAction-validation.xml and logincontext is the param in LoginAction-validation.xml.
Meanewhile, field name is still a member variable in RegisterAction.java and LoginAction.java, which needs to be validated.

User-registercontext-validation.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 
 3              "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd" >
 4  <!--   validator method 2:  -->
 5 
 6  < validators >
 7       < field  name ="username" >
 8           < field-validator  type ="requiredstring" >
 9               < message > Your username: </ message >
10           </ field-validator >
11       </ field >
12       < field  name ="password" >
13           < field-validator  type ="requiredstring" >
14               < message > Your password: </ message >
15           </ field-validator >
16       </ field >
17        < field  name ="email" >
18           < field-validator  type ="requiredstring" >
19               < message > Your email: </ message >
20           </ field-validator >
21       </ field >
22  </ validators >

User-logincontext-validation.xml

 1  <? xml version="1.0" encoding="UTF-8" ?>
 2  <! DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 
 3              "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd" >
 4  <!--   validator method 2:  -->
 5 
 6  < validators >
 7       < field  name ="username" >
 8           < field-validator  type ="requiredstring" >
 9               < message > your username: </ message >
10           </ field-validator >
11       </ field >
12       < field  name ="password" >
13           < field-validator  type ="requiredstring" >
14               < message > your password: </ message >
15           </ field-validator >
16       </ field >
17  </ validators >

Now check the file structure which should follow this way:


Now, re-edit register.jsp and login.jsp which have the corresponding fielderrors:

register.jsp

 1  <% @ page language = " java "  contentType = " text/html; charset=UTF-8 "
 2      pageEncoding = " UTF-8 " %>
 3  <% @ taglib prefix = " s "  uri = " /struts-tags " %>
 4  <! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
 5  < html >
 6  < head >
 7  < meta  http-equiv ="Content-Type"  content ="text/html; charset=UTF-8" >
 8  < title > New User Registration </ title >
 9  </ head >
10  < body >
11  < s:form  action ="register"  theme ="simple" >
12       < table  style ="border-collapse: collapse"  align ="left"
13          bordercolor =#3f8805  cellspacing =0  cellpadding =0  width ="20%"  border =1 >
14           < tr >
15               < td > username </ td >
16               < td >
17                   < s:fielderror  name ="user"  cssStyle ="color:red" >
18                       < s:param > user.username </ s:param >
19                   </ s:fielderror >
20                   < s:textfield  name ="user.username" ></ s:textfield >
21               </ td >
22           </ tr >
23           < tr >
24               < td > password </ td >
25               < td >
26                   < s:fielderror  name ="user"  cssStyle ="color:red" >
27                       < s:param > user.password </ s:param >
28                   </ s:fielderror >
29                   < s:password  name ="user.password" ></ s:password >
30               </ td >
31           </ tr >
32           < tr >
33               < td > re-password </ td >
34               < td >
35                   < s:fielderror  cssStyle ="color:red" >
36                       < s:param > repassword </ s:param >
37                   </ s:fielderror >
38                   < s:password  name ="repassword" ></ s:password >
39               </ td >
40           </ tr >
41           < tr >
42               < td > firstname </ td >
43               < td >< s:textfield  name ="user.firstname" ></ s:textfield ></ td >
44           </ tr >
45           < tr >
46               < td > lastname </ td >
47               < td >< s:textfield  name ="user.lastname" ></ s:textfield ></ td >
48           </ tr >
49           < tr >
50               < td > email </ td >
51               < td >
52                   < s:fielderror  name ="user"  cssStyle ="color:red" >
53                       < s:param > user.email </ s:param >
54                   </ s:fielderror >
55                   < s:textfield  name ="user.email" ></ s:textfield >
56               </ td >
57           </ tr >
58           < tr >
59               < td > street address </ td >
60               < td >< s:textfield  name ="user.street" ></ s:textfield ></ td >
61           </ tr >
62           < tr >
63               < td > city </ td >
64               < td >< s:textfield  name ="user.city" ></ s:textfield ></ td >
65           </ tr >
66           < tr >
67               < td > state </ td >
68               < td >< s:textfield  name ="user.state" ></ s:textfield ></ td >
69           </ tr >
70           < tr >
71               < td > zip code </ td >
72               < td >< s:textfield  name ="user.zip" ></ s:textfield ></ td >
73           </ tr >
74           < tr >
75               < td ></ td >
76               < td >< s:submit ></ s:submit >   < s:reset ></ s:reset ></ td >
77           </ tr >
78       </ table >
79  </ s:form >
80  </ body >
81  </ html >

login.jsp

 1  <% @ page language = " java "  contentType = " text/html; charset=UTF-8 "
 2      pageEncoding = " UTF-8 " %>
 3  <% @ taglib prefix = " s "  uri = " /struts-tags " %>
 4  <! DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" >
 5  < html >
 6  < head >
 7  < meta  http-equiv ="Content-Type"  content ="text/html; charset=UTF-8" >
 8  < title > Login </ title >
 9  </ head >
10  < body >
11  <% --  action = " login "  actually can work  with  this  error .  -- %>
12  < s:form  action ="login"  theme ="simple" >
13       < table  style ="border-collapse: collapse"  align ="left"
14          bordercolor =#3f8805  cellspacing =0  cellpadding =0  width ="20%"  border =1 >
15           < tr >
16               < td > username </ td >
17               < td >
18                   < s:fielderror  name ="user"  cssStyle ="color:red" >
19                       < s:param > user.username </ s:param >
20                   </ s:fielderror >
21                   < s:textfield  name ="user.username" ></ s:textfield >
22               </ td >
23           </ tr >
24          
25           < tr >
26               < td > password </ td >
27               < td >
28                   < s:fielderror  name ="user"  cssStyle ="color:red" >
29                       < s:param > user.password </ s:param >
30                   </ s:fielderror >
31                   < s:password  name ="user.password" ></ s:password >
32               </ td >
33           </ tr >
34           < tr >
35               < td ></ td >
36               < td >
37                   < s:submit ></ s:submit >
38                   < s:reset ></ s:reset >
39               </ td >
40           </ tr >
41       </ table >
42  </ s:form >
43  </ body >
44  </ html >

Be careful about fielderror  name and s:param's text.

The result are like these 2:




Now I have finished all the detail configurations. There're 3 kinkds of servier side validators.

About the validator type, such as 'required', 'requiredstring', 'data' and their value scope will be introduced later.