Simple low-level real-time threading semantics to enable portability, efficiency, analyzability, and generality

ABSTRACT

Among the key reasons why the Java platform has become the most popular programming language for traditional non-real-time development are its portability across a wide variety of popular operating systems and architectures and its built-in language support for threading and synchronization [1, 2]. These are both critical enablers for the creation of a vibrant after market for commercial off the shelf and open source software components. And they are key reasons why software maintenance and reuse of Java software is typically five to ten times less expensive than comparable activities for software implemented in C or C++ [3, 4]. The portable thread model defined by the Java Language Specification [5] does not specify behavior that is important to real-time developers. Though the Real-Time Specification for Java (RTSJ) [6] improves upon standard edition semantics, it still leaves many aspects of threading behavior imprecisely specified and/or implementation defined. This hinders software reuse and adds complexity and costs to software maintenance activities. This paper suggests an alternative approach that improves portability and efficiency, without sacrificing important analyzability and generality requirements.

REFERENCES

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INDEX TERMS

Primary Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.3 Language Constructs and Features
          Subjects: Concurrent programming structures

Additional Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.3 Language Constructs and Features
          Subjects: Modules, packages

General Terms:
Languages, Performance

Keywords:
Java, RTSJ, real-time, safety-critical certification, threading