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Featherweight Java: a minimal core calculus for Java and GJ

Authors:

Atsushi Igarashi,

Benjamin C. Pierce,

Philip WadlerAuthors Info & Claims

ACM Transactions on Programming Languages and Systems (TOPLAS), Volume 23, Issue 3

Pages 396 - 450

https://doi.org/10.1145/503502.503505

Published: 01 May 2001 Publication History

Abstract

Several recent studies have introduced lightweight versions of Java: reduced languages in which complex features like threads and reflection are dropped to enable rigorous arguments about key properties such as type safety. We carry this process a step further, omitting almost all features of the full language (including interfaces and even assignment) to obtain a small calculus, Featherweight Java, for which rigorous proofs are not only possible but easy. Featherweight Java bears a similar relation to Java as the lambda-calculus does to languages such as ML and Haskell. It offers a similar computational "feel," providing classes, methods, fields, inheritance, and dynamic typecasts with a semantics closely following Java's. A proof of type safety for Featherweight Java thus illustrates many of the interesting features of a safety proof for the full language, while remaining pleasingly compact. The minimal syntax, typing rules, and operational semantics of Featherweight Java make it a handy tool for studying the consequences of extensions and variations. As an illustration of its utility in this regard, we extend Featherweight Java with generic classes in the style of GJ (Bracha, Odersky, Stoutamire, and Wadler) and give a detailed proof of type safety. The extended system formalizes for the first time some of the key features of GJ.

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Cited By

Abounegm AKudasov NStepanov A(2024)Teaching Type Systems Implementation with Stella, an Extensible Statically Typed Programming LanguageElectronic Proceedings in Theoretical Computer Science10.4204/EPTCS.405.1405(1-19)Online publication date: 10-Jul-2024
https://doi.org/10.4204/EPTCS.405.1
Frank JQuiring BLampropoulos L(2024)Generating Well-Typed Terms That Are Not “Useless”Proceedings of the ACM on Programming Languages10.1145/36329198:POPL(2318-2339)Online publication date: 5-Jan-2024
https://dl.acm.org/doi/10.1145/3632919
Audrito GCasadei RDamiani FSalvaneschi GViroli M(2024)The eXchange Calculus (XC)Journal of Systems and Software10.1016/j.jss.2024.111976210:COnline publication date: 1-Apr-2024
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Index Terms

Featherweight Java: a minimal core calculus for Java and GJ
1. Software and its engineering
  1. Software notations and tools
    1. Formal language definitions
    2. General programming languages
      1. Language features
        Classes and objects
        Polymorphism
      2. Language types
        Object oriented languages
2. Theory of computation
  1. Formal languages and automata theory
  2. Semantics and reasoning
    1. Program constructs
      1. Object oriented constructs

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Published In

cover image ACM Transactions on Programming Languages and Systems

ACM Transactions on Programming Languages and Systems Volume 23, Issue 3

May 2001

178 pages

ISSN:0164-0925

EISSN:1558-4593

DOI:10.1145/503502

Issue’s Table of Contents

Copyright © 2001 ACM.

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Association for Computing Machinery

New York, NY, United States

Publication History

Published: 01 May 2001

Published in TOPLAS Volume 23, Issue 3

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Cited By

Abounegm AKudasov NStepanov A(2024)Teaching Type Systems Implementation with Stella, an Extensible Statically Typed Programming LanguageElectronic Proceedings in Theoretical Computer Science10.4204/EPTCS.405.1405(1-19)Online publication date: 10-Jul-2024
https://doi.org/10.4204/EPTCS.405.1
Frank JQuiring BLampropoulos L(2024)Generating Well-Typed Terms That Are Not “Useless”Proceedings of the ACM on Programming Languages10.1145/36329198:POPL(2318-2339)Online publication date: 5-Jan-2024
https://dl.acm.org/doi/10.1145/3632919
Audrito GCasadei RDamiani FSalvaneschi GViroli M(2024)The eXchange Calculus (XC)Journal of Systems and Software10.1016/j.jss.2024.111976210:COnline publication date: 1-Apr-2024
https://dl.acm.org/doi/10.1016/j.jss.2024.111976
Yoshida N(2024)Programming Language Implementations with Multiparty Session TypesActive Object Languages: Current Research Trends10.1007/978-3-031-51060-1_6(147-165)Online publication date: 29-Jan-2024
https://doi.org/10.1007/978-3-031-51060-1_6
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Rossberg A(2023)Mutually Iso-Recursive SubtypingProceedings of the ACM on Programming Languages10.1145/36228097:OOPSLA2(347-373)Online publication date: 16-Oct-2023
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Lazarek LGreenman BFelleisen MDimoulas C(2023)How to Evaluate Blame for Gradual Types, Part 2Proceedings of the ACM on Programming Languages10.1145/36078367:ICFP(159-186)Online publication date: 31-Aug-2023
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Ângelo PBono VDezani-Ciancaglini MFlorido MTomb A(2023)Gradual Guarantee for FJ with lambda-ExpressionsProceedings of the 25th ACM International Workshop on Formal Techniques for Java-like Programs10.1145/3605156.3606453(32-38)Online publication date: 18-Jul-2023
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