Rupiah: An extension to Java supporting match-bounded parametric polymorphism, ThisType, and exact typing

The programming language Java [AG96] has gained widespread acceptance throughout the computer industry. Java's type system, though, is lacking in flexibility. This lack of flexibility limits the expressiveness of the language, especially for the creation of container classes. To improve Java's expressiveness, we extend its type system through the addition of three constructs: match-bounded parametric polymorphism, ThisType, and exact typing. These constructs allow a programmer to write flexible, extensible, and statically type-safe code. Our current implementation targets the standard Java Virtual Machine through a source-level translation. Translation allows Rupiah programs to be run on existing Java installations, but carries with it a performance cost. We conclude with a comparison of our language changes and implementation and other proposals for extended Java. Contents 1 Introduction 1 1.1 Outline of the thesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2..