Presentation 4Cross Language Clone Analysis

Team 2October 13, 2010

• Current Tasks• Spike – GOLD Parser • Demo• Project Layout• Team Collaboration• Path Forward

Agenda

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Allen Tucker Patricia Bradford Greg Rodgers Brian Bentley Ashley Chafin

Our Team

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Current TasksWhat we are tackling…

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Current tasks created for the first user story “Source Code Load & Translate”:◦ Load & parse C# source code.◦ Load & parse JAVA source code.◦ Load & parse C++ source code.◦ Translate the parsed C# source code to

CodeDOM.◦ Translate the parsed JAVA source code to

CodeDOM.◦ Translate the parsed C++ source code to

CodeDOM.◦ Associate the CodeDOM to the original source

code.

Current Tasks (Review)

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UML Model – Load & Parse

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UML Model – Translate

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UML Model – Associate

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GOLD Parsing SystemSpike

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Topics To Discuss What is it? How does it work? What can we use it for? How can we extend it?

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What Is GOLD? GOLD is a free parsing system that you can

use to develop your own programming languages, scripting languages and interpreters. It strives to be a development tool that can be used with numerous programming languages and on multiple platforms. – www.devincook.com/goldparser

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How It Works (Block Structure)

Grammar Builder

Compiled Grammar

Table (*.cgt)

Engine

Source Code

Parsed

Data

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How It Works (Components)

Grammar Builder

Compiled Grammar

Table (*.cgt)

Engine

Source Code

Parsed

Data

Three Major Components1. Builder – Reads a source

grammar to construct a Compiled Grammar Table

2. Compiled Grammar Table – Stores LALR and DFA parse tables

3. Engine – Performs actual parsing

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How It Works (Process)

Grammar Builder

Compiled Grammar

Table (*.cgt)

Engine

Source Code

Parsed

Data

Step 1• Write the grammar for the

language being implemented. (GOLD-Meta Language)• Rules: Backus-Naur Form• Terminals: Regular Expressions• Character sets: Set Notation

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How It Works (Process)

Grammar Builder

Compiled Grammar

Table (*.cgt)

Engine

Source Code

Parsed

Data

Step 2• Analyze Grammar• Construct LALR and DFA parse

tables which are saved in a Compiled Grammar Table file.

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How It Works (Process)

Grammar Builder

Compiled Grammar

Table (*.cgt)

Engine

Source Code

Parsed

Data

Step 3• Analyze source text with parser

engine and construct parse tree• Engine can be implemented in

any number of programming languages

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Usage within CloneDigger

Compiled Grammar

Table (*.cgt)

Engine

Source Code

Parsed

Data

CodeDOM Conversion• Need to write routine to move

data from Parsed Tree to CodeDOM• Parsed data trees from parser

are stored in consistent data structure, but are based on rules defined within grammars

CodeDOM Conversi

on

AST

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Task Understanding Three Step Process

• Step 1 Code Translation

• Step 2 Clone Detection

• Step 3 Visualization

Source Files

TranslatorCommon

Model

Common Model

InspectorDetected Clones

Detected Clones

UIClone

Visualization

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Extension and Enhancements

Grammar Builder

Compiled Grammar

Table (*.cgt)

Engine

Source Code

Parsed

Data

Enhance Grammars• Update Java• Update C#• Define C++

• Share among other classmates with similar interest

• Share with greater community

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Grammars What is a grammar?

◦ A set of rules of a specific kind, for forming strings in a formal language. The rules describe how to form strings from the language's alphabet that are valid according to the language's syntax. A grammar does not describe the meaning of the strings or what can be done with them in whatever context —only their form.

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Gold Parser Grammars Gold Parser uses context-free grammars

that can be used to do Lookahead Left-to-Right (LALR) parsing.

LALR compliant grammars that we already have:◦ C#◦ Java◦ Visual Basic .Net

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Grammar Example

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C++ Grammar Issue Currently no LALR compliant C++ grammar

exists due to the overall complexity.

Other C++ parsers exist, but give an output format different than the other languages we already have grammars for using Gold Parser.

We are still searching for C++ parsing solutions.

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We plan to use GOLD Parsing System. Tasks we have to complete:

◦ Update JAVA grammer◦ Update C# grammer◦ Research “Define C++ grammer”◦ Create a CodeDOM conversion to move data from

Parsed Tree to CodeDOM

GOLD Parser Conclusion

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DemonstrationsGOLD Parsing System

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Project LayoutKey Points, Architecture, & Unit Test

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Key Architecture Points Multilanguage support

Configurable for different platforms◦ Stand-along application◦ plug-in◦ backend service

Extendable

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Architecture

C# Service

Java Service

C++ Service

User Interface

Communication Layer

Code Model

Clone Detection Algorithms

Core

API

Language Service Interface

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Visual Studio Solution

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Core Unit Code Model

◦ Stores the code in common format Application Programming Interface

◦ Used to embed clone detection in applications Language Service Interface

◦ Communication layer between the core and the specific language services

Code ModelClone Detection

Algorithms

Core

API

Language Service Interface

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Core

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Core - API

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Language Service

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Language Service

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Language Service

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App Configuration

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Unit Testing

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Team CollaborationTeam 2 & Team 4

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Team Collaboration Due to Team 4’s team size, we have taken

responsibility of gathering & sharing grammers.

Both Teams will…◦ Use the same grammers & engines

We will both have limitations based on this. Ex: JAVA grammer is based off 1.4 -> we are limited to

using JAVA 1.4

◦ Test the same grammers & engines We will have two test beds.

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Team Collaboration Method of collaboration:

◦ Google code project site: http://code.google.com/p/uah-studio-2010-2011/ Team 4 team members have access to this site.

◦ Meetings◦ Email

What does our google code project contain?◦ Source control for grammers & engines◦ Bugs/Issues

Team 4 will have ability to document new bugs.◦ Documents/Artifacts

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Path ForwardNext Iteration & Schedule

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Finalize Iteration 1 Iteration 2 Planning/Elaboration

Path Forward

Schedule