Java Program Analysis Projects in Osaka University: AspectBased Slicing System ADAS and RankedCompon

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Java Program Analysis Projects in Osaka
UniversityAspect-Based Slicing System ADAS
andRanked-Component Search System SPARS-J

• Reishi Yokomori, Takashi Ishio,
• Tetsuo Yamamoto, Makoto Matsushita,
• Shinji Kusumoto and Katsuro Inoue

yokomori, t-isio, t-yamamt, matusita, kusumoto,
inoue_at_ist.osaka-u.ac.jp
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Background

• Large scale software is difficult to debug.
• Especially, fault localization needs much cost
  since the place where a program crushed is not
  always close to the fault.
• Executed codes for one test case are usually
  small pieces of the program.

Excluding automatically unrelated codes is
effective for fault localization.
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Program Slicing

• Program Slicing extracts a slice of codes, which
  affects value of a specific variable.
• Program Slicing excludes unrelated codes to aid
  fault localization.

1 a 5 2 b a a 3 if (b gt 0) 4 c
a 5 6 d b
1 a 5 2 b a a 3 if (b gt 0) 4 c
a 5 6 d b
a slice based on slice criteria(6, b)
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Slice Calculation Process

• Phase 1 Extraction of
• dependence relations.
• Data Dependence
• Control Dependence
• Phase 2 Construction of
• Program Dependence Graph
• node a statement.
• edge a dependence relation
• Phase 3 Traversal of PDG
• traversal backward from a node
• corresponding a slice criteria

slice criteria
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Dependence-Cache (DC) slicing using dynamic
information

• In slice calculation process, observing program
  execution, and using information about statements
  actually executed is effective to decrease the
  slice size.
• which method is actually executed ?
• what type of object is accessed ?
• Dependence-Cache (DC) slicing has been proposed
  for use in a dynamic data dependence analysis and
  a static control dependence analysis to calculate
  accurate slices with lightweight costs .

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Implementation of dynamic analysis

• Although various ways exist in implementing the
  dynamic analysis, each one requires a high cost
  in implementation or in runtime.
• Aspect-oriented programming improves modularity
  of crosscutting concerns.
• Dynamic analysis is a typical crosscutting
  concern.

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Aspect-Oriented Dynamic Analysis and Slicing
Calculation System ADAS

• Debugging Support Tool using Program Slicing for
  Java
• Dynamic Analysis Aspect (written in AspectJ)
• Simple logging-like Implementation
• Lightweight Analysis
• less overhead The aspect is linked to target
  program at compile time.
• coarse analysis The aspect ignore local data and
  controls.
• Program Slicing System
• Program Slicing is an application using dynamic
  information.
• The prototype is implemented as Eclipse plug-in.

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Architecture and Use Case of ADAS
1.edit
program slice
slice criteria
4.slice calculation
Dynamic Analysis Aspect
Java Source
Slice Calculation Tool
Static Analyzer
2.compile
Java VM
AspectJ
Java Bytecode
3.execute a test case
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Demonstration
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Remark and Future Work

• ADAS supports debugging tasks
• Program slicing shows related code to a user.
• Dynamic information exclude unexecuted code.
• Dynamic Analysis Aspect is
• simple implementation,
• easy to maintain, customize.
• Future Work
• Extension of ADAS to calculate AspectJ slice,
• Improvement of Usability.

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Java Program Analysis Projects in Osaka
UniversityAspect-Based Slicing System ADAS
andRanked-Component Search System SPARS-J

• Reishi Yokomori, Takashi Ishio,
• Tetsuo Yamamoto, Makoto Matsushita,
• Shinji Kusumoto and Katsuro Inoue

yokomori, t-isio, t-yamamt, matusita, kusumoto,
inoue_at_ist.osaka-u.ac.jp
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Reuse of Software Components

• Reuse of software components
• is a technique of developing new software
  components by using the components developed in
  the past.
• Example of reusable components source code,
  document ..
• improves productivity and quality, and cuts down
  development cost as a result.
• However, reuse of components is not utilized
  effectively.
• A developer doesnt know existence of desirable
  components.
• Although there are a lot of components, these
  components are not organized.
• In order to take advantage of reuse, it is
  required to share the knowledge of components.

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Motivation of Our Research

• We can get a lot of source codes easily through
  the Internet.
• Software development communities, such as
  SourceForge, release source code For promotion of
  exchanges of views and information between
  developers.
• Publishing companies of programming guide book
  open the example programs to the public.
• These source codes can be helpful as a source of
  knowledge about reusable components.
• A search engine for the components collected from
  the Internet is useful to reuse of components.

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SPARS

• SPARS Software Product Archiving, analyzing and
  Retrieving System
• Now, we are developing
  for Java codes.
• In SPARS,
• Components (source codes) are collected from the
  Internet.
• Components are analyzed syntactically.
• A search engine is built based on the analysis
  information.
• In order to make a search engine user-friendly,
• The components used repeatedly are displayed on
  the higher rank of a search result.
• The evaluation value of each component is
  calculated from the use relation between
  components. (Component Rank)
• Information of the component is displayed in an
  easy-to-understand way.
• Source code
• Other components which it uses
• Similar components

Katsuro Inoue, Reishi Yokomori, Hikaru Fujiwara,
Tetsuo Yamamoto, Makoto Matsushita, Shinji
Kusumoto "Component Rank Relative Significance
Rank for Software Component Search", ICSE,
Portland, OR, May 6, 2003.
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Structure of
Repository Construction Subsystem
Analyzer
Source Code Repository
Ranker
Parser
Cluster
Repository
Word Repository
Query Parser
Searcher
Component Repository
Browser
Formatter
Repository
Retrieval Subsystem
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Demonstration
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Summary and Future Work

• Summary
• We developed component search engine SPARS-J
• By ranking using Component Rank, retrieval of
  components used well is enabled easily.
• We expect a promotion of reuse by sharing of
  knowledge about component.
• Future Work
• Improvement in a performance of SPARS-J
• Improvement in a retrieval function
• Examination of the component information to
  display
• Evaluation of SPARS-J