Walkabout Revisited: The Runabout

  • Christian Grothoff
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2743)


We present a variation of the visitor pattern which allows programmers to write visitor-like code in a concise way. The Runabout is a library extension that adds a limited form of multi-dispatch to Java. While the Runabout is not as expressive as a general multiple dispatching facility, the Runabout can be significantly faster than existing implementations of multiple dispatch for Java, such as MultiJava. Unlike MultiJava, the Runabout does not require changes to the syntax and the compiler.

In this paper we illustrate how to use the Runabout, detail its implementation and provide benchmarks comparing its performance with other approaches.


Dynamic Type Dynamic Code Visitor Pattern Innermost Loop Public Class 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Christian Grothoff
    • 1
  1. 1.S3 lab, Department of Computer SciencesPurdue University 

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