Component NextGen: A Sound and Expressive Component Framework for Java

Developing a general component system for a statically typed, object-oriented language is a challenging design problem for two reasons. First, mutually recursive references across components are common in object-oriented programs - an issue that has proven troublesome in the context of component systems for functional and procedural languages. Second, inheritance across component boundaries can cause accidental method overrides. The recent research shows that a component framework can be constructed for a nominally typed object-oriented language supporting first-class1 generic types simply by adding appropriate annotations, syntactic sugar, and component-level type-checking.