This example presents the basic concept of using in Spring MVC bean validation.

The technologies used are :

– Spring 4.3.18
– JDK 1.80
– Maven 3.3.9

You can convert this example to an Eclipse IDE project by going to folder where is the pom.xml is, and use the command :

mvn eclipse:eclipse

Inspired from « Beginning Spring » Mert Caliskan, Kenan Sevindik, Rod Johnson (Foreword by), Jürgen Höller (Foreword by).

package javaspringexamples.spring.beanvalidation.domain;

import javax.validation.constraints.Pattern;
import javax.validation.constraints.Size;

/**
 * 
 * @author mounir.sahrani@gmail.com
 *
 */
public class User {

	@Size(min = 3, max = 20)
	String username;

	@Pattern(regexp = "^[a-zA-Z]\\w{3,14}$")
	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;
	}
}

Pattern.user.password=Error format: at least 4 letters, max 15.
Size.user.username=Error format: at least 3, max 20.

package javaspringexamples.spring.beanvalidation.controller;

import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

import javaspringexamples.spring.beanvalidation.domain.User;

import javax.validation.Valid;

/**
 * 
 * @author mounir.sahrani@gmail.com
 *
 */

@Controller
public class UserController {

	@RequestMapping(value = "/form")
	public ModelAndView initiateUser() {
		return new ModelAndView("userForm", "user", new User());
	}

	@RequestMapping(value = "/result", method = RequestMethod.POST)
	public ModelAndView processUser(@Valid User user, BindingResult result) {
		ModelAndView modelAndView = new ModelAndView();
		modelAndView.addObject("usr", user);

		if (result.hasErrors()) {
			modelAndView.setViewName("userForm");
		} else {
			modelAndView.setViewName("userResult");
		}

		return modelAndView;
	}
}

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
	  http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
	version="3.1">

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

	<servlet-mapping>
		<servlet-name>springmvc</servlet-name>
		<url-pattern>*.mvc</url-pattern>
	</servlet-mapping>

</web-app>

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:mvc="http://www.springframework.org/schema/mvc"
	xsi:schemaLocation="http://www.springframework.org/schema/beans 
       					   http://www.springframework.org/schema/beans/spring-beans-4.0.xsd 
       					   http://www.springframework.org/schema/context
       					   http://www.springframework.org/schema/context/spring-context-4.0.xsd
       					   http://www.springframework.org/schema/mvc 
       					   http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">

	<context:component-scan
		base-package="javaspringexamples.spring.beanvalidation.controller" />
	<context:annotation-config />
	<mvc:annotation-driven validator="validator" />

	<bean
		class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/views/" />
		<property name="suffix" value=".jsp" />
	</bean>

	<bean id="messageSource"
		class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
		<property name="basename" value="classpath:errorMessages" />
	</bean>

	<bean id="validator"
		class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean">
		<property name="validationMessageSource" ref="messageSource" />
	</bean>
</beans>

<%
	response.sendRedirect("form.mvc");
%>

<%@ page contentType="text/html; charset=ISO-8859-1"%>
<%@taglib uri="http://www.springframework.org/tags/form" prefix="mvc"%>
<html>
<head>
<title>JavaSpringExamples Spring MVC Form</title>
<style type="text/css">
.formFieldError {
	background-color: #FFC;
}
</style>
</head>
<body>

	<h2>Form</h2>
	<mvc:form modelAttribute="user" action="result.mvc">
		<table>
			<tr>
				<td><mvc:label path="username">Login</mvc:label></td>
				<td><mvc:input path="username" cssErrorClass="formFieldError" /></td>
				<td><mvc:errors path="username" /></td>
			</tr>
			<tr>
				<td><mvc:label path="password">Password</mvc:label></td>
				<td><mvc:password path="password"
						cssErrorClass="formFieldError" /></td>
				<td><mvc:errors path="password" /></td>
			</tr>
			<tr>
				<td colspan="3"><input type="submit" value="Submit" /></td>
			</tr>
		</table>
	</mvc:form>
</body>
</html>

<%@ page contentType="text/html; charset=ISO-8859-1"%>
<%@taglib uri="http://www.springframework.org/tags/form" prefix="mvc"%>
<html>
<head>
<title>JavaSpringExamples Spring MVC Form</title>
</head>
<body>
	<h2>Result Form</h2>
	<table>
		<tr>
			<td>login :</td>
			<td>${usr.username}</td>
		</tr>
		<tr>
			<td>Password :</td>
			<td>${usr.password}</td>
		</tr>
	</table>
</body>
</html>

Get the sources of the example from the following GitHub url

Or Download a .zip file