To compile this class you would need the JavaFX classes on the compile path. With the Oracle JDK they are shipped with the main JDK, not sure about OpenJDK. There they might be separate.

The class in question makes something like this possible:

@Min(value = 3)
IntegerProperty integerProperty1 = new SimpleIntegerProperty( 4 );

This is a Hibernate Validator specific feature which goes beyond the specified Bean Validation 1.1 spec. See also - http://docs.jboss.org/hibernate/validator/5.2/reference/en-US/html_single/#section-javafx-unwrapper

The problem is really just a compile time problem. The usage of this class is already via reflection and the feature only gets enabled in case JavaFX is detected on the the class path.

So, I guess what I am saying here is that using the Oracle JDK or a JDK with JavaFX classes provided is a must to built a master of Hibernate Validator.