We present a non-null annotations inferencer for the Java bytecode language. We previously proposed an analysis to infer non-null annotations and proved it soundness and completeness with respect to a state of the art type system. This paper proposes extensions to our former analysis in order to deal with the Java bytecode language. We have implemented both analyses and compared their behaviour on several benchmarks. The results show a substantial improvement in the precision and, despite being a whole-program analysis, production applications can be analyzed within minutes. Categories and Subject Descriptors F.3.2 [Logics and Meanings of Programs]: Semantics of Programming Languages--program analysis; D.3.3 [Programming Languages]: Language Constructs and Fea