The class OptionalBoolean does part of JavaFX and is insclused in HotSpot. The problem is that class does not exist in OpenJDK project, so not compile the project with OpenJDK. It's important to say with JSR 336, the Java 7, the OpenJDK project is Reference implementation. This way our project just compile in Oracle's JVM.
Ref: https://jcp.org/en/jsr/detail?id=336 Sugetsion: Just use Optional<Boolean> instead, this way we have garanty all JVM will compile and run this project. -- Otávio Gonçalves de Santana blog: http://otaviosantana.blogspot.com.br/ twitter: http://twitter.com/otaviojava site: *http://about.me/otaviojava <http://about.me/otaviojava>* 55 (11) 98255-3513
