java - 约束验证

Question

我正在使用javax.validation.Validator和相关类进行基于注释的验证。

Configuration<?> configuration = Validation.byDefaultProvider().configure();   
ValidatorFactory factory = configuration.buildValidatorFactory();   
Validator validator = factory.getValidator(); 

Set<ConstraintViolation<ValidatableObject>> constraintViolations = validator.validate(o);   
for (ConstraintViolation<ValidatableObject> value : constraintViolations) {   
     List< Class< ? extends ConstraintValidator< ? extends Annotation,?>>> list = 
             value.getConstraintDescriptor().getConstraintValidatorClasses();  
}

我收到一个编译错误，指出:

Type mismatch: cannot convert from List< Class< ? extends ConstraintValidator< capture#4-of ?,?>>> to List< Class< ? extends ConstraintValidator< ? extends Annotation,?>>>

我错过了什么？

Answer 1

如果您不介意与 ConstraintValidator<?, ?> 合作(即您不需要 ConstraintValidator<? extends Annotation, ?> )，这应该有效:

Configuration<?> configuration = Validation.byDefaultProvider().configure();   
ValidatorFactory factory = configuration.buildValidatorFactory();   
Validator validator = factory.getValidator(); 

Set<ConstraintViolation<ValidatableObject>> constraintViolations = validator.validate(o);   
for (ConstraintViolation<ValidatableObject> value : constraintViolations) {   
     List< Class< ? extends ConstraintValidator<?,?>>> list = 
             value.getConstraintDescriptor().getConstraintValidatorClasses();  
}