Create Spring MVC Project
On the Eclipse, create a Spring MVC project in Spring Boot
Enter Project Information:
- Name: LearnSpringMVCWithRealApps
- Group: com.demo
- Artifact: LearnSpringMVCWithRealApps
- Description: Learn Spring MVC with Real Apps
- Package: com.demo
Select the technologies and libraries to be used:
- Web
Click Next button to show Site Information for project
Click Finish button to finish create Spring MVC project
Configure pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.demo</groupId>
<artifactId>LearnSpringMVCWithRealApps</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>LearnSpringMVCWithRealApps</name>
<description>Learn Spring MVC with Real Apps</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.RELEASE</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<!-- Spring MVC -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- JSTL tag lib -->
<dependency>
<groupId>javax.servlet.jsp.jstl</groupId>
<artifactId>javax.servlet.jsp.jstl-api</artifactId>
<version>1.2.1</version>
</dependency>
<dependency>
<groupId>taglibs</groupId>
<artifactId>standard</artifactId>
<version>1.1.2</version>
</dependency>
<!-- Tomcat for JSP rendering -->
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-jasper</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
Error Messages
Create new properties file, named messages.properties in src\main\resources folder. This file contains error messages for validation.
NotEmpty=This field is required.
Length=Please enter a value between {2} and {1} characters long.
Min=Please enter a value greater than or equal to {1}.
Max=Please enter a value less than or equal to {1}.
NotNull=This field is required.
account.username.exists=Username already exists.
typeMismatch.int=Please enter a valid number.
URL.website=Please enter a valid URL.
Email=Please enter a valid email address.
StrongPassword=Password does not meet complexity requirements.
typeMismatch={0} is of invalid format.
Pattern={0} must match pattern for complexity requirements.
Configure application.properties
spring.mvc.view.prefix = /WEB-INF/views/
spring.mvc.view.suffix = .jsp
spring.mvc.static-path-pattern=/resources/**
server.port=9596
Configure Spring MVC
package com.demo;
import org.springframework.context.MessageSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.support.ResourceBundleMessageSource;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
@Configuration
public class SpringMVCConfiguration extends WebMvcConfigurerAdapter {
@Bean
public MessageSource messageSource() {
ResourceBundleMessageSource resourceBundleMessageSource = new ResourceBundleMessageSource();
resourceBundleMessageSource.setBasename("messages");
return resourceBundleMessageSource;
}
}
Validation Groups
In com.demo.entities package, create validation groups as below:
Group 1
Create new java interface, named Group1.java
package com.demo.entities;
public interface Group1 {
}
Group 2
Create new java interface, named Group2.java
package com.demo.entities;
public interface Group2 {
}
Entities Class
Create new package, named com.demo.entities. In this package, create entities class as below:
Account Entity
Create new java class, named Account.java
package com.demo.entities;
import org.hibernate.validator.constraints.NotEmpty;
public class Account {
@NotEmpty(groups = { Group1.class, Group2.class })
private String username;
@NotEmpty(groups = { Group1.class })
private String password;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
Create Validator
Create new package named com.demo.validators. In this package, create new validator named AccountValidator as below:
package com.demo.validators;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;
import com.demo.entities.Account;
public class AccountValidator implements Validator {
@Override
public boolean supports(Class> arg0) {
return Account.class.equals(arg0);
}
@Override
public void validate(Object object, Errors errors) {
}
}
Create Controller
Create new package named com.demo.controllers. In this package, create new controller named AccountController as below:
package com.demo.controllers;
import org.springframework.stereotype.*;
import org.springframework.ui.ModelMap;
import org.springframework.validation.BindingResult;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;
import com.demo.entities.Account;
import com.demo.entities.Group1;
import com.demo.entities.Group2;
import com.demo.validators.AccountValidator;
@Controller
@RequestMapping("account")
public class AccountController {
@RequestMapping(value = "register", method = RequestMethod.GET)
public String register(ModelMap modelMap) {
modelMap.put("account", new Account());
return "account/register";
}
@RequestMapping(value = "register", method = RequestMethod.POST)
public String register(@Validated({ Group1.class }) @ModelAttribute("account") Account account,
BindingResult bindingResult, ModelMap modelMap) {
AccountValidator accountValidator = new AccountValidator();
accountValidator.validate(account, bindingResult);
if (bindingResult.hasErrors()) {
return "account/register";
} else {
modelMap.put("account", account);
return "account/success1";
}
}
@RequestMapping(value = "edit", method = RequestMethod.GET)
public String edit(ModelMap modelMap) {
modelMap.put("account", new Account());
return "account/edit";
}
@RequestMapping(value = "edit", method = RequestMethod.POST)
public String edit(@Validated({ Group2.class }) @ModelAttribute("account") Account account,
BindingResult bindingResult, ModelMap modelMap) {
AccountValidator accountValidator = new AccountValidator();
accountValidator.validate(account, bindingResult);
if (bindingResult.hasErrors()) {
return "account/edit";
} else {
modelMap.put("account", account);
return "account/success2";
}
}
}
Create View
Create new folders with path webapp\WEB-INF\views in src\main. In views folder, create new folder named account. In account folder, create JSP Pages as below:
Register View
Create new jsp file named register.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="http://www.springframework.org/tags/form"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Account Register</title>
</head>
<body>
<h3>Account Register</h3>
<s:form method="post" commandName="account"
action="${pageContext.request.contextPath }/account/register">
<table cellpadding="2" cellspacing="2">
<tr>
<td>Username</td>
<td><s:input path="username" /></td>
<td><s:errors path="username"></s:errors></td>
</tr>
<tr>
<td>Password</td>
<td><s:password path="password" /></td>
<td><s:errors path="password"></s:errors></td>
</tr>
<tr>
<td> </td>
<td><input type="submit" value="Save"></td>
</tr>
</table>
</s:form>
</body>
</html>
Success 1 View
Create new jsp file named success1.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Success 1 Page</title>
</head>
<body>
<h3>Success 1 Page</h3>
<table cellpadding="2" cellspacing="2" border="1">
<tr>
<td>Username</td>
<td>${account.username }</td>
</tr>
<tr>
<td>Password</td>
<td>${account.password }</td>
</tr>
</table>
</body>
</html>
Edit View
Create new jsp file named edit.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="http://www.springframework.org/tags/form"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Update Account</title>
</head>
<body>
<h3>Update Account</h3>
<s:form method="post" commandName="account"
action="${pageContext.request.contextPath }/account/edit">
<table cellpadding="2" cellspacing="2">
<tr>
<td>Username</td>
<td><s:input path="username" /></td>
<td><s:errors path="username"></s:errors></td>
</tr>
<tr>
<td>Password</td>
<td><s:password path="password" /></td>
<td><s:errors path="password"></s:errors></td>
</tr>
<tr>
<td> </td>
<td><input type="submit" value="Save"></td>
</tr>
</table>
</s:form>
</body>
</html>
Success 2 View
Create new jsp file named success2.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Success 2 Page</title>
</head>
<body>
<h3>Success 2 Page</h3>
<table cellpadding="2" cellspacing="2" border="1">
<tr>
<td>Username</td>
<td>${account.username }</td>
</tr>
<tr>
<td>Password</td>
<td>${account.password }</td>
</tr>
</table>
</body>
</html>
Structure of Spring MVC Project
Run Application
Select LearnSpringMVCWithRealAppsApplication.java file in com.demo package, right click and select Run As/Spring Boot App menu
Validate with Group 1
Access register method in account controller with following url: http://localhost:9596/account/register
Output
Click Save button submit form to register method in account controller with invalid data as below:
Output
Click Save button submit form to register method in account controller with valid data
Output
Validate with Group 2
Access edit method in account controller with following url: http://localhost:9596/account/edit
Output
Click Save button submit form to edit method in account controller with invalid data as below:
Output
Click Save button submit form to edit method in account controller with valid data
Output
References
I recommend you refer to the books below to learn more about the knowledge in this article:
- Spring MVC Beginners Guide – Second Edition
- Spring MVC Cookbook
- Spring MVC Blueprints
- Mastering Spring MVC 4
- Spring Boot in Action
- Pro Spring Boot