Removing duplication from java.io: a case study using traits

ABSTRACT

Code duplication is a serious problem with no easy solution, even in industrial-strength code. Single inheritance cannot provide for effective code reuse in all situations, and sometimes programmers are driven to duplicate code using copy and paste. A language feature called traits enables code to be shared across the inheritance hierarchy, and claims to permit the removal of most duplication. We attempted to validate this claim in a case study of the java.io library. Detecting duplication was more complex than we had imagined, but traits were indeed able to remove all that we found.

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INDEX TERMS

Primary Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
        D.2.13 Reusable Software

Additional Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.3 Language Constructs and Features
          Subjects: Classes and objects; Inheritance

Keywords:
Java IO class libraries, refactoring, traits