Mục lục

Giới thiệu
Chuẩn bị database
Tạo Project
Cấu hình Web.xml & Maven
Cấu hình Spring MVC
Các class tham gia vào ví dụ
Spring MVC Validator
Spring Controller
Các file Jsps
Chạy ứng dụng

Hướng dẫn sử dụng Spring MVC Form và Hibernate

Xem thêm các chuyên mục:

Các hướng dẫn Spring MVC

Giới thiệu
Chuẩn bị database
Tạo Project
Cấu hình Web.xml & Maven
Cấu hình Spring MVC
Các class tham gia vào ví dụ
Spring MVC Validator
Spring Controller
Các file Jsps
Chạy ứng dụng

1- Giới thiệu

Tài liệu được viết dựa trên:

Spring MVC 4.2.5
Hibernate 5.x
Database: Oracle, MySQL, SQL Server

Xem trước ví dụ:

Xem thêm:

Tạo ứng dụng đăng ký tài khoản với Spring Boot, Spring Form Validation

2- Chuẩn bị database

ORACLE

-- Create table
create table APPLICANTS
(
  ID       VARCHAR2(50) not null,
  GENDER   VARCHAR2(10) not null,
  NAME     VARCHAR2(50) not null,
  POSITION VARCHAR2(50) not null,
  SKILLS   VARCHAR2(255) not null,
  EMAIL    VARCHAR2(50) not null
) ;

alter table APPLICANTS
  add constraint APPLICANT_PK primary key (ID);

MYSQL & SQL SERVER

-- Create table
create table APPLICANTS
(
  ID       VARCHAR(50) not null,
  GENDER   VARCHAR(10) not null,
  NAME     VARCHAR(50) not null,
  POSITION VARCHAR(50) not null,
  SKILLS   VARCHAR(255) not null,
  EMAIL    VARCHAR(50) not null,
  primary key (ID)
) ;

3- Tạo Project

Trên Eclipse chọn:

File/New/Others..

Group Id: org.o7planning
Artifact Id: SpringMVCAnnotationForm

Project đã được tạo ra.

Sửa project:

Nhấn phải chuột vào Project chọn Properties.

Chọn Java Compiler 7 hoặc 8:

4- Cấu hình Web.xml & Maven

Bạn cần phải sửa web.xml để sử dụng Web App 3.x.

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"
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
 id="WebApp_ID" version="3.0">

 <display-name>Spring MVC Form</display-name>
 

</web-app>

Cấu hình Maven:

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
  http://maven.apache.org/maven-v4_0_0.xsd">
 
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.o7planning</groupId>
  <artifactId>SpringMVCAnnotationForm</artifactId>
  <packaging>war</packaging>
  <version>1.0.0</version>
  <name>SpringMVCAnnotationForm Maven Webapp</name>
  <url>http://maven.apache.org</url>


  <properties>
      <java-version>1.7</java-version>
  </properties>

  <repositories>
      <!-- Repository for ORACLE JDBC Driver -->
      <repository>
          <id>codelds</id>
          <url>https://code.lds.org/nexus/content/groups/main-repo</url>
      </repository>
  </repositories>

  <dependencies>

      <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>3.8.1</version>
          <scope>test</scope>
      </dependency>

      <!-- Servlet API -->
      <!-- http://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
      <dependency>
          <groupId>javax.servlet</groupId>
          <artifactId>javax.servlet-api</artifactId>
          <version>3.1.0</version>
          <scope>provided</scope>
      </dependency>

      <!-- Jstl for jsp page -->
      <!-- http://mvnrepository.com/artifact/javax.servlet/jstl -->
      <dependency>
          <groupId>javax.servlet</groupId>
          <artifactId>jstl</artifactId>
          <version>1.2</version>
      </dependency>


      <!-- JSP API -->
      <!-- http://mvnrepository.com/artifact/javax.servlet.jsp/jsp-api -->
      <dependency>
          <groupId>javax.servlet.jsp</groupId>
          <artifactId>jsp-api</artifactId>
          <version>2.2</version>
          <scope>provided</scope>
      </dependency>

      <!-- Spring dependencies -->
      <!-- http://mvnrepository.com/artifact/org.springframework/spring-core -->
      <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-core</artifactId>
          <version>4.2.5.RELEASE</version>
      </dependency>

      <!-- http://mvnrepository.com/artifact/org.springframework/spring-web -->
      <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-web</artifactId>
          <version>4.2.5.RELEASE</version>
      </dependency>

      <!-- http://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
      <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-webmvc</artifactId>
          <version>4.2.5.RELEASE</version>
      </dependency>

      <!-- http://mvnrepository.com/artifact/org.springframework/spring-orm -->
      <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-orm</artifactId>
          <version>4.2.5.RELEASE</version>
      </dependency>

      <!-- Hibernate -->
      <!-- http://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
      <dependency>
          <groupId>org.hibernate</groupId>
          <artifactId>hibernate-core</artifactId>
          <version>5.1.0.Final</version>
      </dependency>

      <!-- http://mvnrepository.com/artifact/org.hibernate/hibernate-entitymanager -->
      <dependency>
          <groupId>org.hibernate</groupId>
          <artifactId>hibernate-entitymanager</artifactId>
          <version>5.1.0.Final</version>
      </dependency>


      <!-- http://mvnrepository.com/artifact/org.hibernate/hibernate-c3p0 -->
      <dependency>
          <groupId>org.hibernate</groupId>
          <artifactId>hibernate-c3p0</artifactId>
          <version>5.1.0.Final</version>
      </dependency>


      <!-- MySQL JDBC driver -->
      <!-- http://mvnrepository.com/artifact/mysql/mysql-connector-java -->
      <dependency>
          <groupId>mysql</groupId>
          <artifactId>mysql-connector-java</artifactId>
          <version>5.1.34</version>
      </dependency>

      <!-- Oracle JDBC driver -->
      <dependency>
          <groupId>com.oracle</groupId>
          <artifactId>ojdbc6</artifactId>
          <version>11.2.0.3</version>
      </dependency>

    <!-- SQLServer JDBC driver (JTDS) -->
    <!-- http://mvnrepository.com/artifact/net.sourceforge.jtds/jtds -->
    <dependency>
        <groupId>net.sourceforge.jtds</groupId>
        <artifactId>jtds</artifactId>
        <version>1.3.1</version>
    </dependency>

    <!-- Email validator,... -->
    <!-- http://mvnrepository.com/artifact/commons-validator/commons-validator -->
    <dependency>
        <groupId>commons-validator</groupId>
        <artifactId>commons-validator</artifactId>
        <version>1.5.0</version>
    </dependency>

  </dependencies>


  <build>
      <finalName>SpringMVCAnnotationForm</finalName>
      <plugins>
    
          <!-- Config: Maven Tomcat Plugin -->
          <!-- http://mvnrepository.com/artifact/org.apache.tomcat.maven/tomcat7-maven-plugin -->
          <plugin>
              <groupId>org.apache.tomcat.maven</groupId>
              <artifactId>tomcat7-maven-plugin</artifactId>
              <version>2.2</version>
              <!-- Config: contextPath and Port (Default - /SpringMVCAnnotationForm : 8080) -->
              <!--
              <configuration>
                  <path>/</path>
                  <port>8899</port>
              </configuration>
              -->   
          </plugin>
      </plugins>
  </build>   
 

</project>

5- Cấu hình Spring MVC

SpringWebAppInitializer sử dụng để khởi tạo các cấu hình Spring, nó là điểm bắt đầu của Spring MVC. Nó thay thế cho việc cấu hình Spring MVC trong web.xml.
** web.xml **


 <servlet>
     <servlet-name>spring-mvc</servlet-name>
     <servlet-class>
         org.springframework.web.servlet.DispatcherServlet
     </servlet-class>
     <load-on-startup>1</load-on-startup>
 </servlet>  

 <servlet-mapping>
     <servlet-name>spring-mvc</servlet-name>
     <url-pattern>/</url-pattern>
 </servlet-mapping>

SpringWebAppInitializer.java

package org.o7planning.springmvcforms.config;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;

import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

public class SpringWebAppInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        AnnotationConfigWebApplicationContext appContext = new AnnotationConfigWebApplicationContext();
        appContext.register(ApplicationContextConfig.class);

        ServletRegistration.Dynamic dispatcher = servletContext.addServlet("SpringDispatcher",
                new DispatcherServlet(appContext));
        dispatcher.setLoadOnStartup(1);
        dispatcher.addMapping("/");
    }

}

Class ApplicationContextConfig sử dụng để cấu hình Spring MVC Context, bao gồm:

View Resolver
Datasouce
Hiberante (Hibernate Transaction Manager, Hibernate Session,..)
DAO
Bean
....

ApplicationContextConfig.java

package org.o7planning.springmvcforms.config;

import java.util.Properties;

import javax.sql.DataSource;

import org.hibernate.SessionFactory;
import org.o7planning.springmvcforms.dao.ApplicantDAO;
import org.o7planning.springmvcforms.dao.impl.ApplicantDAOImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.support.ResourceBundleMessageSource;
import org.springframework.core.env.Environment;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.hibernate5.HibernateTransactionManager;
import org.springframework.orm.hibernate5.LocalSessionFactoryBean;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.servlet.view.InternalResourceViewResolver;

@Configuration
@ComponentScan("org.o7planning.springmvcforms.*")
@EnableTransactionManagement
// Load to Environment.
@PropertySource("classpath:ds-hibernate-cfg.properties")
public class ApplicationContextConfig {



  // Lưu trữ các giá thuộc tính load bởi @PropertySource.
  @Autowired
  private Environment env;
 
 

  @Bean
  public ResourceBundleMessageSource messageSource() {
      ResourceBundleMessageSource rb = new ResourceBundleMessageSource();
      // Load property in message/validator.properties
      rb.setBasenames(new String[] { "messages/validator"});
      return rb;
  }
 

  @Bean(name = "viewResolver")
  public InternalResourceViewResolver getViewResolver() {
      InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
      viewResolver.setPrefix("/WEB-INF/pages/");
      viewResolver.setSuffix(".jsp");
      return viewResolver;
  }

  @Bean(name = "dataSource")
  public DataSource getDataSource() {
      DriverManagerDataSource dataSource = new DriverManagerDataSource();

      dataSource.setDriverClassName(env.getProperty("ds.database-driver"));
      dataSource.setUrl(env.getProperty("ds.url"));
      dataSource.setUsername(env.getProperty("ds.username"));
      dataSource.setPassword(env.getProperty("ds.password"));

      return dataSource;
  }

  @Autowired
  @Bean(name = "sessionFactory")
  public SessionFactory getSessionFactory(DataSource dataSource) throws Exception {
      Properties properties = new Properties();

      // Xem: ds-hibernate-cfg.properties
      properties.put("hibernate.dialect", env.getProperty("hibernate.dialect"));
      properties.put("hibernate.show_sql", env.getProperty("hibernate.show_sql"));
      properties.put("current_session_context_class", env.getProperty("current_session_context_class"));
     

      LocalSessionFactoryBean factoryBean = new LocalSessionFactoryBean();
      factoryBean.setPackagesToScan(new String[] { "org.o7planning.springmvcforms.entity" });
      factoryBean.setDataSource(dataSource);
      factoryBean.setHibernateProperties(properties);
      factoryBean.afterPropertiesSet();
      //
      SessionFactory sf = factoryBean.getObject();
      return sf;
  }

  @Autowired
  @Bean(name = "transactionManager")
  public HibernateTransactionManager getTransactionManager(SessionFactory sessionFactory) {
      HibernateTransactionManager transactionManager = new HibernateTransactionManager(sessionFactory);

      return transactionManager;
  }

  @Bean(name = "applicantDAO")
  public ApplicantDAO getApplicantDAO() {
      return new ApplicantDAOImpl();
  }

}

ApplicationContextConfig sẽ đọc các thông tin cấu hình Datasource, Hibernate properties trong file ds-hibernate-cfg.properties.

Các cấu hình dành cho Oracle, MySQL hoặc SQL Server:

ds-hibernate-cfg.properties (For ORACLE)


# DataSource

ds.database-driver=oracle.jdbc.driver.OracleDriver
ds.url=jdbc:oracle:thin:@localhost:1521:db12c
ds.username=shoppingcart
ds.password=12345


# Hibernate Config

hibernate.dialect=org.hibernate.dialect.Oracle10gDialect
hibernate.show_sql=true
current_session_context_class=thread

ds-hibernate-cfg.properties (For MYSQL)


# DataSource

ds.database-driver=com.mysql.jdbc.Driver
ds.url=jdbc:mysql://localhost:3306/mydatabase
ds.username=root
ds.password=12345


# Hibernate Config

hibernate.dialect=org.hibernate.dialect.MySQLDialect
hibernate.show_sql=true
current_session_context_class=thread

ds-hibernate-cfg.properties (For SQL SERVER)


# DataSource

ds.database-driver=net.sourceforge.jtds.jdbc.Driver
ds.url=jdbc:jtds:sqlserver://localhost:1433/simplehr;instance=SQLEXPRESS
ds.username=shoppingcart
ds.password=12345


# Hibernate Config

hibernate.dialect=org.hibernate.dialect.SQLServerDialect
hibernate.show_sql=true
current_session_context_class=thread

Cấu hình để sử dụng các nguồn tĩnh (html, image, css,..)

WebMvcConfig.java

package org.o7planning.springmvcforms.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;


@Configuration
@EnableWebMvc
public class WebMvcConfig extends WebMvcConfigurerAdapter {

 
 
   // Cấu hình để sử dụng các file nguồn tĩnh (html, image, ..)
   // Tương đương với <mvc:resources/> trong cấu hình sử dụng XML.
   @Override
   public void addResourceHandlers(ResourceHandlerRegistry registry) {
       registry.addResourceHandler("/css/**").addResourceLocations("/css/").setCachePeriod(31556926);
       registry.addResourceHandler("/img/**").addResourceLocations("/img/").setCachePeriod(31556926);
       registry.addResourceHandler("/js/**").addResourceLocations("/js/").setCachePeriod(31556926);
   }

   // equivalent for <mvc:default-servlet-handler/> tag
   @Override
   public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
       configurer.enable();
   }

}

6- Các class tham gia vào ví dụ

Applicant là một entity class, mô phỏng bảng APPLICANTS trong database.

Applicant.java

package org.o7planning.springmvcforms.entity;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "Applicants")
public class Applicant implements Serializable {

   private static final long serialVersionUID = -7893237204476214050L;
   private String id;
   private String name;
   private String email;

   private String position;
   private String gender;
   private String skills;

   @Id
   @Column(name = "ID", length = 50, nullable = false)
   public String getId() {
       return id;
   }

   public void setId(String id) {
       this.id = id;
   }

   @Column(name = "Name", length = 50, nullable = false)
   public String getName() {
       return name;
   }

   public void setName(String name) {
       this.name = name;
   }

   @Column(name = "Position", length = 50, nullable = false)
   public String getPosition() {
       return position;
   }

   public void setPosition(String position) {
       this.position = position;
   }

   @Column(name = "Gender", length = 10, nullable = false)
   public String getGender() {
       return gender;
   }

   public void setGender(String gender) {
       this.gender = gender;
   }

   @Column(name = "Email", length = 50, nullable = false)
   public String getEmail() {
       return email;
   }

   public void setEmail(String email) {
       this.email = email;
   }

   @Column(name = "Skills", length = 255, nullable = false)
   public String getSkills() {
       return skills;
   }

   public void setSkills(String skills) {
       this.skills = skills;
   }
}

ApplicantInfo.java

package org.o7planning.springmvcforms.model;

public class ApplicantInfo {

   private String id;
   private String name;
   private String email;

   private String position;
   private String gender;
   private String skillsString;
   private String[] skills;

   public ApplicantInfo() {

   }

 
   // Không được thay đổi Constructor này,
   // Nó được sử dụng trong Hibernate Query.
   public ApplicantInfo(String id, String name, String email, String gender, String position, String skillsString) {
       this.id = id;
       this.name = name;
       this.email = email;

       this.position = position;
       this.gender = gender;
       this.skillsString = skillsString;
       this.skills = toArray(skillsString);
   }

   private String[] toArray(String skillStrings) {
       if (skillStrings == null) {
           return new String[0];
       }
       String[] ret = skillStrings.split(",");
       return ret;
   }

   public String getId() {
       return id;
   }

   public void setId(String id) {
       this.id = id;
   }

   public String getName() {
       return name;
   }

   public void setName(String name) {
       this.name = name;
   }

   public String getEmail() {
       return email;
   }

   public void setEmail(String email) {
       this.email = email;
   }

   public String getPosition() {
       return position;
   }

   public void setPosition(String position) {
       this.position = position;
   }

   public String getGender() {
       return gender;
   }

   public void setGender(String gender) {
       this.gender = gender;
   }

   public String[] getSkills() {
       return skills;
   }

   public void setSkills(String[] skills) {
       this.skills = skills;
       this.skillsString = this.joinString(skills);
   }

   private String joinString(String[] skills) {
       if (skills == null) {
           return "";
       }
       return String.join(",", skills);
   }

   public String getSkillsString() {
       return this.skillsString;
   }

}

ApplicantDAO là một Spring Bean, để xử lý các insert, update, query dữ liệu trên bảng APPLICANTS.

ApplicantDAO.java

package org.o7planning.springmvcforms.dao;

import java.util.List;

import org.o7planning.springmvcforms.entity.Applicant;
import org.o7planning.springmvcforms.model.ApplicantInfo;

public interface ApplicantDAO {

    public Applicant findApplicant(String id);

    public List<ApplicantInfo> listApplicantInfos();

    public void saveApplicant(ApplicantInfo applicantInfo);

    public ApplicantInfo findApplicantInfo(String id);

    public void deleteApplicant(String id);
   
}

ApplicantDAOImpl.java

package org.o7planning.springmvcforms.dao.impl;

import java.util.List;
import java.util.UUID;

import org.hibernate.Criteria;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.Restrictions;
import org.o7planning.springmvcforms.dao.ApplicantDAO;
import org.o7planning.springmvcforms.entity.Applicant;
import org.o7planning.springmvcforms.model.ApplicantInfo;
import org.springframework.beans.factory.annotation.Autowired;

public class ApplicantDAOImpl implements ApplicantDAO {

    @Autowired
    private SessionFactory sessionFactory;

    @Override
    public Applicant findApplicant(String id) {
        Session session = sessionFactory.getCurrentSession();
        Criteria crit = session.createCriteria(Applicant.class);
        crit.add(Restrictions.eq("id", id));
        return (Applicant) crit.uniqueResult();
    }

    @Override
    public ApplicantInfo findApplicantInfo(String id) {
        Applicant applicant = this.findApplicant(id);
        if (applicant == null) {
            return null;
        }
        return new ApplicantInfo(applicant.getId(), applicant.getName(), //
                applicant.getEmail(), applicant.getGender(), //
                applicant.getPosition(), applicant.getSkills());
    }

    @Override
    public List<ApplicantInfo> listApplicantInfos() {
        String sql = "Select new " + ApplicantInfo.class.getName()//
                + "(a.id, a.name, a.email, a.gender, a.position, a.skills) "//
                + " from " + Applicant.class.getName() + " a ";
        Session session = sessionFactory.getCurrentSession();
        Query query = session.createQuery(sql);
        return query.list();
    }

    public void saveApplicant(ApplicantInfo applicantInfo) {
        String id = applicantInfo.getId();
        Applicant applicant = null;
        if (id != null) {
            applicant = this.findApplicant(id);
        }
        boolean isNew = false;
        if (applicant == null) {
            isNew = true;
            applicant = new Applicant();
            applicant.setId(UUID.randomUUID().toString());
        }
        applicant.setEmail(applicantInfo.getEmail());
        applicant.setGender(applicantInfo.getGender());
        applicant.setName(applicantInfo.getName());
        applicant.setPosition(applicantInfo.getPosition());
        String skillsString = applicantInfo.getSkillsString();

        applicant.setSkills(skillsString);
        //

        if (isNew) {
            Session session = this.sessionFactory.getCurrentSession();
            session.persist(applicant);
        }
    }

    @Override
    public void deleteApplicant(String id) {
        Applicant applicant = this.findApplicant(id);
        if (applicant != null) {
            this.sessionFactory.getCurrentSession().delete(applicant);
        }
    }

}

7- Spring MVC Validator

ApplicantValidator là class để validate dữ liệu người dùng nhập vào form. Trong trường hợp người dùng nhập sai, sẽ có các thông báo như hình minh họa dưới đây:

ApplicantValidator.java

package org.o7planning.springmvcforms.validator;

import org.apache.commons.validator.routines.EmailValidator;
import org.o7planning.springmvcforms.model.ApplicantInfo;
import org.springframework.stereotype.Component;
import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator;

@Component
public class ApplicantValidator implements Validator {
 
   // common-validator library.
   private EmailValidator emailValidator =   EmailValidator.getInstance();

 
   // Các class được hỗ trợ Validate
   @Override
   public boolean supports(Class<?> clazz) {
       return clazz == ApplicantInfo.class;
   }

   @Override
   public void validate(Object target, Errors errors) {
       ApplicantInfo applicantInfo = (ApplicantInfo) target;

 
       // Kiểm tra các field của ApplicantInfo.
       // (Xem thêm file property: messages/validator.property)
       ValidationUtils.rejectIfEmptyOrWhitespace(errors, "name", "NotEmpty.applicantForm.name");
       ValidationUtils.rejectIfEmptyOrWhitespace(errors, "email", "NotEmpty.applicantForm.email");
       ValidationUtils.rejectIfEmptyOrWhitespace(errors, "position", "NotEmpty.applicantForm.position");
       ValidationUtils.rejectIfEmptyOrWhitespace(errors, "gender", "NotEmpty.applicantForm.gender");
     
       if(!emailValidator.isValid(applicantInfo.getEmail())) {
           // Error in email field.
           // Lỗi trường email.
           errors.rejectValue("email", "Pattern.applicantForm.email");
       }
     
       if(applicantInfo.getSkills()== null || applicantInfo.getSkills().length==0 ) {
           errors.rejectValue("skills", "Select.applicantForm.skills");
       }
   
   }

}

Các lỗi thông báo được cấu hình trong file messages/validator.properties:

messages/validator.properties

NotEmpty.applicantForm.name=Name is required
NotEmpty.applicantForm.email=Email is required
NotEmpty.applicantForm.position=Position is required
NotEmpty.applicantForm.gender=Gender is required

Pattern.applicantForm.email=Email is not valid

Select.applicantForm.skills=Must select at least one skill

Nội dung của validator.properties đã được load (tải vào ứng dụng) bởi ApplicationContextConfig:

** ApplicationContextConfig.java **

// Load property in message/validator.properties

@Bean
public ResourceBundleMessageSource messageSource() {
   ResourceBundleMessageSource rb = new ResourceBundleMessageSource();
   // Load property in message/validator.properties
   rb.setBasenames(new String[] { "messages/validator"});
   return rb;
}

8- Spring Controller

MyController.java

package org.o7planning.springmvcforms.controller;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.o7planning.springmvcforms.dao.ApplicantDAO;
import org.o7planning.springmvcforms.model.ApplicantInfo;
import org.o7planning.springmvcforms.validator.ApplicantValidator;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;

@Controller
// Cần thiết cho Hibernate Transaction.
@Transactional
// Cần thiết để sử dụng RedirectAttributes
@EnableWebMvc
public class MyController {

   @Autowired
   private ApplicantDAO applicantDAO;

   @Autowired
   private ApplicantValidator applicantValidator;

   @RequestMapping("/")
   public String homePage(Model model) {

       return applicantList(model);
   }

   @RequestMapping("/applicantList")
   public String applicantList(Model model) {
       List<ApplicantInfo> list = applicantDAO.listApplicantInfos();
       model.addAttribute("applicantInfos", list);
       return "applicantList";
   }

   private Map<String, String> dataForPositions() {
       Map<String, String> positionMap = new LinkedHashMap<String, String>();
       positionMap.put("Developer", "Developer");
       positionMap.put("Leader", "Leader");
       positionMap.put("Tester", "Tester");
       return positionMap;
   }

   private List<String> dataForSkills() {
       List<String> list = new ArrayList<String>();
       list.add("Java");
       list.add("C/C++");
       list.add("C#");
       return list;
   }

   private String formApplicant(Model model, ApplicantInfo applicantInfo) {
       model.addAttribute("applicantForm", applicantInfo);

       Map<String, String> positionMap = this.dataForPositions();

       model.addAttribute("positionMap", positionMap);

       List<String> list = dataForSkills();
       model.addAttribute("skills", list);

       if (applicantInfo.getId() == null) {
           model.addAttribute("formTitle", "Create Applicant");
       } else {
           model.addAttribute("formTitle", "Edit Applicant");
       }

       return "formApplicant";
   }

   @RequestMapping("/createApplicant")
   public String createApplicant(Model model) {

       ApplicantInfo applicantInfo = new ApplicantInfo();

       return this.formApplicant(model, applicantInfo);
   }

   @RequestMapping("/editApplicant")
   public String editApplicant(Model model, @RequestParam("id") String id) {
       ApplicantInfo applicantInfo = null;
       if (id != null) {
           applicantInfo = this.applicantDAO.findApplicantInfo(id);
       }
       if (applicantInfo == null) {
           return "redirect:/applicantList";
       }

       return this.formApplicant(model, applicantInfo);
   }

   @RequestMapping("/deleteApplicant")
   public String deleteApplicant(Model model, @RequestParam("id") String id) {
       if (id != null) {
           this.applicantDAO.deleteApplicant(id);
       }
       return "redirect:/applicantList";
   }

   // Set a form validator
   @InitBinder
   protected void initBinder(WebDataBinder dataBinder) {
  
       // Form mục tiêu
       Object target = dataBinder.getTarget();
       if (target == null) {
           return;
       }
       System.out.println("Target=" + target);

       if (target.getClass() == ApplicantInfo.class) {
           dataBinder.setValidator(applicantValidator);
       }
   }

   // Save or update Applicant
   // 1. @ModelAttribute bind form value
   // 2. @Validated form validator
   // 3. RedirectAttributes for flash value
   @RequestMapping(value = "/saveApplicant", method = RequestMethod.POST)
   public String saveApplicant(Model model, //
           @ModelAttribute("applicantForm") @Validated ApplicantInfo applicantInfo, //
           BindingResult result, //
           final RedirectAttributes redirectAttributes) {

       // Nếu validate có lỗi.
       if (result.hasErrors()) {
           return this.formApplicant(model, applicantInfo);
       }

       this.applicantDAO.saveApplicant(applicantInfo);

       // Important!!: Need @EnableWebMvc
       // Add message to flash scope
       redirectAttributes.addFlashAttribute("message", "Save Applicant Successful");

       return "redirect:/applicantList";

   }

}

9- Các file Jsps

WEB-INF/pages/applicantList.jsp

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Applicant List</title>
<style>
   table  {
       margin-top: 10px;
       border: solid black 1px;
   }
   table  td {
        padding: 5px;
   }
   .message  {
        font-size:90%;
        color:blue;
        font-style:italic;
        margin-top:30px;
   }
</style>
</head>
<body>



<a href="${pageContext.request.contextPath}/createApplicant">Create Applicant</a>

<br/>


<table border="1">
 <tr>
   <th>Name</th>
   <th>Position</th>
   <th>Gender</th>
   <th>Email</th>
   <th>Skills</th>
   <th>Edit</th>
   <th>Delete</th>
 </tr>
 <c:forEach items="${applicantInfos}" var="info">

 <tr>
   <td> ${info.name}  </td>
   <td> ${info.position}  </td>
   <td> ${info.gender} </td>
   <td> ${info.email} </td>
   <td> ${info.skillsString} </td>
   <td> <a href="deleteApplicant?id=${info.id}">Delete</a> </td>
   <td> <a href="editApplicant?id=${info.id}">Edit</a> </td>
 </tr>    

 </c:forEach>
</table>
<c:if test="${not empty message}">
 
   <div class="message">${message}</div>
</c:if>



</body>
</html>

WEB-INF/pages/formApplicant.jsp

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<%@ taglib prefix="spring" uri="http://www.springframework.org/tags"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>

<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Create Applicant</title>
<style>
.error-message {
   color: red;
   font-size:90%;
   font-style: italic;
}
</style>
</head>
<body>

   <h3>${formTitle}</h3>

   <form:form action="saveApplicant" method="POST"
       modelAttribute="applicantForm">

       <form:hidden path="id" />

       <table>
           <tr>
               <td>Name</td>
               <td><form:input path="name" /></td>
               <td><form:errors path="name"
                       class="error-message" /></td>      
           </tr>
           <tr>
               <td>Gender</td>
               <td><form:select path="gender">
                       <form:option value="" label="- Gender -" />
                       <form:option value="M" label="Male" />
                       <form:option value="F" label="Female" />
                   </form:select></td>
               <td><form:errors path="gender" class="error-message" /></td>
           </tr>
           <tr>
               <td>Email</td>
               <td><form:input path="email" /></td>
               <td><form:errors path="email" class="error-message" /></td>
           </tr>
           <tr>
               <td>Position</td>
               <td><form:select path="position">
                       <form:options items="${positionMap}" />
                   </form:select></td>
               <td><form:errors path="position" class="error-message" /></td>
           </tr>

           <tr>
               <td>Skills</td>
               <td><c:forEach items="${skills}" var="skill">
                       <form:checkbox path="skills" value="${skill}" label="${skill}" />
                   </c:forEach></td>
               <td><form:errors path="skills" class="error-message" /></td>
           </tr>

           <tr>
               <td>&nbsp;</td>
               <td><input type="submit" value="Submit" />
                  <a href="${pageContext.request.contextPath}/applicantList">Cancel</a>
               </td>
               <td>&nbsp;</td>
           </tr>
       </table>
   </form:form>

</body>
</html>