Dependency Injection in JSR-303 Constraint Validator with Spring fails - spring

Question

I have the same problem as here and here but couldn't find a solution yet.
So my sample test project will show the whole relevant configuration and code:
Constraint annotation:
#Target({ ElementType.METHOD, ElementType.FIELD })
#Retention(RetentionPolicy.RUNTIME)
#Constraint(validatedBy = FooValidator.class)
public #interface FooValid {
String message();
Class<?>[] groups() default {};
Class<? extends Payload>[] payload() default {};
}
Annotated PoJo:
public class Foo {
#FooValid(message = "Test failed")
private Integer test;
[...]
}
Annotated Service with #Validated:
#Service
#Validated
public class FooService {
private final Test test;
#Autowired
public FooService(final Test test) {
this.test = test;
}
public void foo(#Valid final Foo foo) {
this.test.test(foo);
}
}
JSR-303 ConstraintValidator:
public class FooValidator implements ConstraintValidator<FooValid, Integer> {
#Autowired
private ValidationService validationService;
#Override
public void initialize(final FooValid constraintAnnotation) {
// TODO Auto-generated method stub
}
#Override
public boolean isValid(final Integer value, final ConstraintValidatorContext context) {
// this.validationService is always NULL!
Assert.notNull(this.validationService, "the validationService must not be null");
return false;
}
}
Injected ValidationService:
#Service
public class ValidationService {
public void test(final Foo foo) {
System.out.println(foo);
}
}
Spring boot application and configuration:
#Configuration
#ComponentScan
#EnableAutoConfiguration
public class Application {
public static void main(final String[] args) {
final ConfigurableApplicationContext context = SpringApplication.run(Application.class, args);
final FooService service = context.getBean(FooService.class);
service.foo(new Foo());
}
#Bean
public static LocalValidatorFactoryBean validatorFactory() {
return new LocalValidatorFactoryBean();
}
#Bean
public static MethodValidationPostProcessor validationPostProcessor() {
return new MethodValidationPostProcessor();
}
}
relevant maven pom:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.1.9.RELEASE</version>
<relativePath/>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
</dependency>
</dependencies>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<start-class>demo.Application</start-class>
<java.version>1.7</java.version>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
I'm using the LocalValidatorFactoryBean with the default SpringConstraintValidatorFactory.
But why the dependency injection is not working in the ConstraintValidator and the ValidationService could not be autowired?
By the way if I don't use #Validated at the service, inject in opposite the spring or javax Validator interface and call manually "validator.validate" the dependency injection will work. But I don't want to call the validate method in every service manually.
Many thanks for help :)

Answer 1

I have fought the same problem in Spring Boot environment and I found out that Hibernate internal implementation got in instead of the configured Spring's one. When the application started, debugger caught a line with the Spring's factory but later in runtime there was Hibernate's one. After some debugging, I came to the conclusion that MethodValidationPostProcessor got the internal one. Therefore I configured it as follows:
#Bean
public Validator validator() {
return new LocalValidatorFactoryBean();
}
#Bean
public MethodValidationPostProcessor methodValidationPostProcessor(Validator validator) {
MethodValidationPostProcessor methodValidationPostProcessor = new MethodValidationPostProcessor();
methodValidationPostProcessor.setValidator(validator);
return methodValidationPostProcessor;
}
Note the setter for validator - it did the job.

Answer 2

I had the same issue. The problem is arises because Hibernate is finding and applying the validators instead of Spring. So you need to set validation mode to NONE when configuring Hibernate:
#Bean(name="entityManagerFactory")
public LocalContainerEntityManagerFactoryBean
localContainerEntityManagerFactoryBean(DataSource dataSource) {
LocalContainerEntityManagerFactoryBean lcemfb =
new LocalContainerEntityManagerFactoryBean();
lcemfb.setDataSource(dataSource);
lcemfb.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
lcemfb.setValidationMode(ValidationMode.NONE);
// Continue configuration...
If you have confgured a LocalValidationFactoryBean Spring will pick up any validators annotated with #Component and autowire them.

Answer 3

This is what worked for me. I had to used the #Inject tag.
public class FooValidator implements ConstraintValidator<FooValid, Integer> {
private ValidationService validationService;
#Inject
public FooValidator(ValidationService validationService){
this.validationService = validationService;
}
#Override
public void initialize(final FooValid constraintAnnotation) {
// TODO Auto-generated method stub
}
#Override
public boolean isValid(final Integer value, final ConstraintValidatorContext context) {
// this.validationService is always NULL!
Assert.notNull(this.validationService, "the validationService must not be null");
return false;
}
}