Prerequisite
add the following dependency in pom.xml:
<dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.10</version> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>4.2.6.RELEASE</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-validator</artifactId> <version>5.2.1.Final</version> </dependency> <dependency> <groupId>javax.el</groupId> <artifactId>javax.el-api</artifactId> <version>2.2.4</version> </dependency> <dependency>
I declare message attribute as NotBlank:
@NotBlank annotation is a “composite” annotation which is based on @NotNull:
And use the following code to explicitly trigger a validation:
public static void main(String[] args) { ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml"); HelloWorld obj = (HelloWorld) context.getBean("helloWorld"); obj.setMessage(null); obj.printMessage(); // http://stackoverflow.com/questions/24386771/javax-validation-validationexception-hv000183-unable-to-load-javax-el-express ValidatorFactory vf = Validation.buildDefaultValidatorFactory(); Validator validator = vf.getValidator(); Set<ConstraintViolation<HelloWorld>> set = validator.validate(obj); for (ConstraintViolation<HelloWorld> constraintViolation : set) { System.out.println(constraintViolation.getMessage()); } }
output:
A list of all available validator annotation
You can find a list of all available validator and their implementation from this folder:
C:\Users\i042416.m2\repository\org\hibernate\hibernate-validator\5.2.1.Final\hibernate-validator-5.2.1.Final\org\hibernate\validator\internal\constraintvalidators\bv
Debug - how does it work?
