Architecture Rules (OV project page) is a Java open source framework licensed under Apache 2.0 that can be used to analyze your code. For the moment it can identify cyclic dependencies among project's packages and classes.
Java PathFinder (JPF) is a system to verify executable Java bytecode programs. In its basic form, it is a Java Virtual Machine (JVM) that is used as an explicit state software model checker, systematically exploring all potential execution paths of a prog