Java Bean Validation - Object Association validation with @Valid

According to the Bean Validation specification, the @Valid annotation on a given object reference is used to allow cascading Validation. The associated object can itself contain cascaded references, hence it is a recursive process. This feature is also referred as 'object graph validation'.

Example

In this example, we are purposely supplying invalid values during object creation to see @Valid annotation in action.

package com.logicbig.example;

import javax.validation.*;
import javax.validation.constraints.Digits;
import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Past;
import java.text.ParseException;
import java.util.Comparator;
import java.util.Date;
import java.util.Set;

public class ValidAnnotationExample {

    private static class DriverLicense {
        @NotNull
        @Valid
        private Driver driver;
        @Digits(integer = 7, fraction = 0)
        private int number;

        public DriverLicense(Driver driver, int number) {
            this.driver = driver;
            this.number = number;
        }
    }

    private static class Driver {
        @NotNull
        private String fullName;
        @Min(100)
        private int height;
        @Past
        @NotNull
        private Date dateOfBirth;

        public Driver(String fullName, int height, Date dateOfBirth) {
            this.dateOfBirth = dateOfBirth;
            this.fullName = fullName;
            this.height = height;
        }
    }

    public static void main(String[] args) throws ParseException {
        Driver driver = new Driver("Joseph Waters", 60,
                new Date(System.currentTimeMillis() + 100000));
        DriverLicense dl = new DriverLicense(driver, 3454343);

        Validator validator = createValidator();
        Set<ConstraintViolation<DriverLicense>> violations = validator.validate(dl);
        if (violations.size() == 0) {
            System.out.println("No violations.");
        } else {
            System.out.printf("%s violations:%n", violations.size());
            violations.stream().sorted(Comparator.comparing(o -> o.getPropertyPath().toString()))
                      .forEach(ValidAnnotationExample::printError);
        }
    }

    private static void printError(ConstraintViolation<?> violation) {
        System.out.println(violation.getPropertyPath()
                + " " + violation.getMessage());
    }

    public static Validator createValidator() {
        Configuration<?> config = Validation.byDefaultProvider().configure();
        ValidatorFactory factory = config.buildValidatorFactory();
        Validator validator = factory.getValidator();
        factory.close();
        return validator;
    }
}

Output

2 violations:
driver.dateOfBirth must be a past date
driver.height must be greater than or equal to 100

Let's remove @Valid annotation in above example:

package com.logicbig.example;

import javax.validation.*;
import javax.validation.constraints.Digits;
import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Past;
import java.text.ParseException;
import java.util.Date;
import java.util.Set;

public class WithoutValidAnnotationExample {

    private static class DriverLicense {
        @NotNull
        private Driver driver;
        @Digits(integer = 7, fraction = 0)
        private int number;

        public DriverLicense(Driver driver, int number) {
            this.driver = driver;
            this.number = number;
        }
    }

    private static class Driver {
        @NotNull
        private String fullName;
        @Min(100)
        private int height;
        @Past
        @NotNull
        private Date dateOfBirth;

        public Driver(String fullName, int height, Date dateOfBirth) {
            this.dateOfBirth = dateOfBirth;
            this.fullName = fullName;
            this.height = height;
        }
    }

    public static void main(String[] args) throws ParseException {
        Driver driver = new Driver("Joseph Waters", 60,
                new Date(System.currentTimeMillis() + 100000));
        DriverLicense dl = new DriverLicense(driver, 3454343);

        Validator validator = createValidator();
        Set<ConstraintViolation<DriverLicense>> violations = validator.validate(dl);
        if (violations.size() == 0) {
            System.out.println("No violations.");
        } else {
            System.out.printf("%s violations:%n", violations.size());
            violations.stream()
                      .forEach(WithoutValidAnnotationExample::printError);
        }
    }

    private static void printError(ConstraintViolation<?> violation) {
        System.out.println(violation.getPropertyPath()
                + " " + violation.getMessage());
    }

    public static Validator createValidator() {
        Configuration<?> config = Validation.byDefaultProvider().configure();
        ValidatorFactory factory = config.buildValidatorFactory();
        Validator validator = factory.getValidator();
        factory.close();
        return validator;
    }
}

Output

No violations.

Example Project

Dependencies and Technologies Used:

• hibernate-validator 6.2.0.Final (Hibernate's Jakarta Bean Validation reference implementation)
   Version Compatibility: 5.0.0.Final - 6.2.0.Final Version List
  ×

  Version compatibilities of hibernate-validator with this example:

  groupId: org.hibernate
  artifactId: hibernate-validator
  Reference implementation for Bean Validation 1.1
  • 5.0.0.Final
  • 5.0.1.Final
  • 5.0.2.Final
  • 5.0.3.Final
  • 5.1.0.Final
  • 5.1.1.Final
  • 5.1.2.Final
  • 5.1.3.Final
  • 5.2.0.Final
  • 5.2.1.Final
  • 5.2.2.Final
  • 5.2.3.Final
  • 5.2.4.Final
  • 5.2.5.Final
  • 5.3.0.Final
  • 5.3.1.Final
  • 5.3.2.Final
  • 5.3.3.Final
  • 5.3.4.Final
  • 5.3.5.Final
  • 5.3.6.Final
  • 5.4.0.Final
  • 5.4.1.Final
  • 5.4.2.Final
  • 5.4.3.Final
  groupId: org.hibernate.validator
  artifactId: hibernate-validator
  Reference implementation for Bean Validation 2.0
  • 6.0.0.Final
  • 6.0.1.Final
  • 6.0.2.Final
  • 6.0.3.Final
  • 6.0.4.Final
  • 6.0.5.Final
  • 6.0.6.Final
  • 6.0.7.Final
  • 6.0.8.Final
  • 6.0.9.Final
  • 6.0.10.Final
  • 6.0.11.Final
  • 6.0.12.Final
  • 6.0.13.Final
  • 6.0.14.Final
  • 6.0.15.Final
  • 6.0.16.Final
  • 6.0.17.Final
  • 6.0.18.Final
  • 6.0.19.Final
  • 6.0.20.Final
  • 6.0.21.Final
  • 6.0.22.Final
  • 6.1.0.Final
  • 6.1.1.Final
  • 6.1.2.Final
  • 6.1.3.Final
  • 6.1.4.Final
  • 6.1.5.Final
  • 6.1.6.Final
  • 6.1.7.Final
  • 6.2.0.Final
  Version 7 and later:
  Jakarta Bean Validation 3.0
  jakarta.* packages

  Versions in green have been tested.

• javax.el-api 3.0.0 (Expression Language 3.0 API)
  
• javax.el 2.2.6 (Expression Language 2.2 Implementation)
  
• JDK 8
• Maven 3.8.1