next → ← prev

Spring MVC Validation

The Spring MVC Validation is used to restrict the input provided by the user. To validate the user's input, the Spring 4 or higher version supports and use Bean Validation API. It can validate both server-side as well as client-side applications.

Bean Validation API

The Bean Validation API is a Java specification which is used to apply constraints on object model via annotations. Here, we can validate a length, number, regular expression, etc. Apart from that, we can also provide custom validations.

As Bean Validation API is just a specification, it requires an implementation. So, for that, it uses Hibernate Validator. The Hibernate Validator is a fully compliant JSR-303/309 implementation that allows to express and validate application constraints.

Validation Annotations

Let's see some frequently used validation annotations.

Annotation	Description
@NotNull	It determines that the value can't be null.
@Min	It determines that the number must be equal or greater than the specified value.
@Max	It determines that the number must be equal or less than the specified value.
@Size	It determines that the size must be equal to the specified value.
@Pattern	It determines that the sequence follows the specified regular expression.

Spring MVC Validation Example

In this example, we create a simple form that contains the input fields. Here, (*) means it is mandatory to enter the corresponding field. Otherwise, the form generates an error.

1. Add dependencies to pom.xml file.

pom.xml

<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>5.1.1.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.tomcat/tomcat-jasper -->
<dependency>
    <groupId>org.apache.tomcat</groupId>
    <artifactId>tomcat-jasper</artifactId>
    <version>9.0.12</version>
</dependency>
    <!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
<dependency>  
    <groupId>javax.servlet</groupId>  
    <artifactId>servlet-api</artifactId>  
    <version>3.0-alpha-1</version>  
</dependency>
<!-- https://mvnrepository.com/artifact/javax.servlet/jstl -->
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
</dependency>
 <!-- https://mvnrepository.com/artifact/org.hibernate.validator/hibernate-validator -->
<dependency>
    <groupId>org.hibernate.validator</groupId>
    <artifactId>hibernate-validator</artifactId>
    <version>6.0.13.Final</version>
</dependency>

2. Create the bean class

Employee.java

package com.javatpoint;
import javax.validation.constraints.Size;

public class Employee {

	private String name;
	@Size(min=1,message="required")
	private String pass;
	
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPass() {
		return pass;
	}
	public void setPass(String pass) {
		this.pass = pass;
	}	
}

3. Create the controller class

In controller class:

The @Valid annotation applies validation rules on the provided object.
The BindingResult interface contains the result of validation.

package com.javatpoint;

import javax.validation.Valid;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class EmployeeController {

	@RequestMapping("/hello")
	public String display(Model m)
	{
		m.addAttribute("emp", new Employee());
		return "viewpage";
	}
	@RequestMapping("/helloagain")
	public String submitForm( @Valid @ModelAttribute("emp") Employee e, BindingResult br)
	{
		if(br.hasErrors())
		{
			return "viewpage";
		}
		else
		{
		return "final";
		}
	}
}

4. Provide the entry of controller in the web.xml file

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" xmlns="https://java.sun.com/xml/ns/javaee" xsi:schemaLocation="https://java.sun.com/xml/ns/javaee https://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>SpringMVC</display-name>
   <servlet>  
    <servlet-name>spring</servlet-name>  
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  
    <load-on-startup>1</load-on-startup>    
</servlet>  
<servlet-mapping>  
    <servlet-name>spring</servlet-name>  
    <url-pattern>/</url-pattern>  
</servlet-mapping>  
</web-app>

5. Define the bean in the xml file

spring-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="https://www.springframework.org/schema/beans"
	xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" 
	xmlns:context="https://www.springframework.org/schema/context"
	xmlns:mvc="https://www.springframework.org/schema/mvc"
	xsi:schemaLocation="
		https://www.springframework.org/schema/beans
    	https://www.springframework.org/schema/beans/spring-beans.xsd
    	https://www.springframework.org/schema/context
    	https://www.springframework.org/schema/context/spring-context.xsd
    	https://www.springframework.org/schema/mvc
        https://www.springframework.org/schema/mvc/spring-mvc.xsd">
	<!-- Provide support for component scanning -->
	<context:component-scan base-package="com.javatpoint" />
	<!--Provide support for conversion, formatting and validation -->
	<mvc:annotation-driven/>
	<!-- Define Spring MVC view resolver -->
     <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/"></property>
        <property name="suffix" value=".jsp"></property>     
     </bean>
</beans>

6. Create the requested page

index.jsp

<%@ taglib prefix="form" uri="https://www.springframework.org/tags/form" %>
<html>
<body>
<a href="hello">Click here...</a>
</body>
</html>

7. Create the other view components

viewpage.jsp

<%@ taglib prefix="form" uri="https://www.springframework.org/tags/form" %>
<html>
<head>
<style>
.error{color:red}
</style>
</head>
<body>
<form:form action="helloagain" modelAttribute="emp">
Username: <form:input path="name"/> <br><br>
Password(*): <form:password path="pass"/>  
<form:errors path="pass" cssClass="error"/><br><br>
<input type="submit" value="submit">
</form:form>
</body>
</html>

final.jsp

<html>
<body>
Username: ${emp.name} <br><br>
Password: ${emp.pass}
</body>
</html>

Output:

Spring MVC Validation

Let's submit the form without entering the password.

Spring MVC Validation

Now, we entered the password and then submit the form.

Spring MVC Validation

Spring MVC Validation

Download this example (developed using Eclipse)

Download Hibernate Validator Jar File

If you are not using maven, download hibernate validator jar.

Next TopicRegular Expression Validation

← prev next →

We provides tutorials and interview questions of all technology like java tutorial, android, java frameworks

Contact info

G-13, 2nd Floor, Sec-3, Noida, UP, 201301, India

[email protected].

Follow us

Tutorials

Java Data Structures C Programming C++ Tutorial C# Tutorial PHP Tutorial HTML Tutorial JavaScript Tutorial jQuery Tutorial Spring Tutorial

Interview Questions

Tcs Intuit Wipro Adobe Infosys Amazon Accenture Cognizant Capgemini Microsoft

Online Compiler

C R C++ Php Java Html Swift Python JavaScript TypeScript

© Copyright 2024 Javatpoint. All Rights Reserved.