Javari: adding reference immutability to Java

This paper describes a type system that is capable of expressing and enforcing immutability constraints. The speonstraint expressed is that the abstract state of the object to which an immutable reference refers cannot be d using that reference. The abstract state is (part of) the transitively reachable state: that is, the state of the object and all state reachable from it by following references. The type system permits explicitly excluding fields from the abstract state of an object. For a statically type-safe language, the type system guarantees reference immutability. If the language is extended with immutability downcasts, then run-time checks enforce the reference immutability constraints. This research builds upon previous research in language support for reference immutability. Improvements that are new in this paper include distinguishing the notions of assignability and mutability; integration with Java 5’s generic types and with multi-dimensional arrays; a mutability po...

• Type: Conference
• Year: 2005
• Where: OOPSLA
• Authors: Matthew S. Tschantz, Michael D. Ernst
• Keywords: Abstract State, Immutability Constraints, OOPSLA 2005, Reference Immutability