Over a million developers have joined DZone.

Spring Bean Custom Validation for Mobile Apps – JSR-303 Annotations

DZone's Guide to

Spring Bean Custom Validation for Mobile Apps – JSR-303 Annotations

This article shows you how to perform Spring Bean custom validations for mobile apps with JSR-303 annotations.

· Mobile Zone
Free Resource

Download this comprehensive Mobile Testing Reference Guide to help prioritize which mobile devices and OSs to test against, brought to you in partnership with Sauce Labs.

This article shows you how to perform Spring Bean custom validations for mobile apps with JSR-303 annotations.

1. Below dependencies should be added to pom.xml to handle spring bean validations:

<!--Java validation jars -->



<!--Hibernate validation jars -->


2. Provide below hibernate validations to your DTO (in this example MyDTO. java):

public class MyDTO {


    @Size(min = 1, max = 16)

    @Pattern(regexp = "[a-zA-Z0-9]+")

    private String name;


    @Size(min = 1, max = 12)

    private String password;


3. messageSource definition should be provided to context.xml(src\main\webapp\WEB-INF\applicationContext.xml). This definition will intialize the messages.properties file:

<bean id="messageSource"     class="org.springframework.context.support.ResourceBundleMessageSource">
    <property name="basenames">

4. Below validation messages should be provided to messages.properties file:

4. Below validation messages should be provied to messages.properties file (src\main\resources\messages.properties) 

NotEmpty ={0} cannot be empty.
Size ={0} should be between {2} and {1} characters.
Pattern = The {0} must be a alphanumeric.

5. Add below definition to your controller to handle validation for DTO object (MyController.java):

import javax.validation.Valid;

public class MyController {

    @RequestMapping(value = "/v1/sessions/login", method = RequestMethod.POST)
    public ResponseEntity<LoginDTO> login(@Valid @RequestBody MyDTO login)
    throws Exception {
        //code goes here



6. Added below Exception handler to your controller advice (MyControllerAdvice.java):

import java.util.ArrayList;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.MessageSource;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;

import com.mypackage.restservices.model.RestErrors;

import com.mypackage.restservices.model.Errors;

public class MyControllerAdvice {

    private MessageSource messageSource;

    protected ResponseEntity<RestErrors>     handleValidationException(MethodArgumentNotValidException ex) {
        List<Errors> errors = new ArrayList<Errors>();
        List<FieldError> fieldErrors = ex.getBindingResult().getFieldErrors();
        for (FieldError fieldError : fieldErrors) {
            Errors error = new Errors();
            error.setDefaultMessage(messageSource.getMessage(fieldError, null));
        RestErrors restErrors = new RestErrors("Validation Failed", errors);
        return new ResponseEntity<RestErrors>(restErrors, HttpStatus.BAD_REQUEST);


7. RestErrors.java changes to display properly to the user:

package com.mypackage.restservices.model;
import java.util.List;
public class RestErrors {

    private String message;
    private List<Errors> errors;
    public RestErrors(String message) {
        this.message = message;
    public RestErrors(String message, List<Errors> errors) {
        this.message = message;
        this.errors = errors;
    public void setMessage(String message) {
        this.message = message;
    public String getMessage() {
        return message;
    public void setErrors(List<Errors> errors) {
        this.errors = errors;
    public List<Errors> getErrors() {
        return errors;

8. Errors.java changes to store error code and default message to be displayed in the UI:

package com.mypackage.restservices.model;

public class Errors {
    private String code;
    private String defaultMessage;
    public String getCode() {
        return code;
    public void setCode(String code) {
        this.code = code;
    public String getDefaultMessage() {
        return defaultMessage;
    public void setDefaultMessage(String defaultMessage) {
        this.defaultMessage = defaultMessage;


Analysts agree that a mix of emulators/simulators and real devices are necessary to optimize your mobile app testing - learn more in this white paper, brought to you in partnership with Sauce Labs.

bean validation api support ,mobile app ,spring validation

Opinions expressed by DZone contributors are their own.

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}