International Conference on Systemics, Cybemetics and Informatics
Automated Code Generation using Generative Programming
Approach for a Mathematical Expression
Sonali Idate
Assistant Professor,
Department of Computer Engineering
and Information Technology,Bharati
Vidyapeeth University college of
Engineering ,Katraj-Dhankawadi,
Pune -43, Maharashtra, India
[email protected]
Dipak J. Mali
Suhas. H. Patil
Professor
Department of Computer Engineering
and Information Technology,Bharati
Vidyapeeth University college of
Engineering .Katraj-Dhankawadi,
Pune -43, Maharashtra, India
Senior software engineer
IBM India Global Services,
TPO, Viman Nagar,Pune
Maharashtra, India
[email protected]
[email protected]
Abstract
The compiler of high-level languages has the ability
to transform a compact representation
of a mathematical
expression borrowed from mathematics into an equivalent but
expansive and complexly interrelated
series of assembly
language instructions. This saves the programmer a significant
amount of work because the mathematical expression is that
are already inherently composite. Even when developers have
recurring computer-readable
metadata to process and a clear
idea of how code should be structured, they can still find
themselves in need of a technique to automatically generate
the code for the mathematical
formula.
Generative
programming is a technique that addresses this problem.
Keywords
Generative programming, lexical analysis, parsing,
code generators, singleton pattern, template pattern
1. Introduction
Even when developers have recurring computerreadable metadata to process and a clear idea of how code
should be structured, they can still find themselves in need of
a technique to automatically
generate the code for the
mathematical formula to avoid the drudge work of repeatedly
writing and tweaking it An important paradigm shift is to
replace manual
search, adaptation,
and assembly
of
components with the automatic
generation
of needed
components on demand.
One important paradigm shift implied here is to build software
systems from standard componentry rather than "reinventing
the wheel" each time. This requires thinking in adaptation,
and assembly of components with the autoniatic generation of
needed
components
on demand.
Generative
software
engineering seeks to integrate domain engineering approaches,
component-based approaches, and generative approaches.[4]
Applying generative programming produces implementation
code from three things:
A means of specifying family members, the implementation
components from which members can be assembled,
The
configuration
knowledge
mapping
between
a
specification of a member and a finished inember.
This article proposes that there is need to industrialise and
mechanise the software development process to a much
greater degree. The process should follow the following
pattern:
1) Iteratively gather requirements and evolve a way to capture
them in models.
2) Extend a code generation platform to derive and generate
the application code lor a specific application platform,
3) Where it isn't cost effective to model and generate, write
components that get weaved into the generated code and
called at the appropriate points.[2.3]
The proposed system Expression Code Generator (ExECG)
follows above pattern and builds a sample template-driven
code generator tor mathematical expression.
3. System Description
2. Relevance To Generative Programming
.
The goal of generative programming in software
~ engineering is to increase the productivity, quality, and time, ~
of system families rather than single systems. Another
.unportant paradigm shift is to replace manual search, to. market in software development thanks to the deployment of
both standard componentry and production automation.
Copyright 0 2008
Number: CC-1.7
This peer-reviewed paper has been published by
the Pentagram Research Centre (P) Limited.
Responsibility of contents of this paper rests upon
the authors and not upon Pentagram Research
Centre (P) Limited. Copies can be obtained from
the company for a cost
Paper Identification
Code Generators
are programs that automatically
generate high-level code (Java, C, C++ etc). ExECG follows
partial class generator type architecture.
Partial. class Generator
A partial class generator builds a set of base classes
to implement a design specitied in a definition file, These base
classes are used as the platform to build the production
classes. The base classes are designed to do the majority of the
low level work of the completed class, leaving the derived
class tree to override specific ~haviors. [1]
134
Automated Code Generation using Generative Programming Approach for a Mathematical Expression
Defud
3.1.2 Code generator
Template
The formula for which the. code is required to be ,.....
generated is parsed and validated against the defmed grammar
rules. Other data viz. Math Rules, JavaDoc generation rules, ..."
Control Structures rules are collected by parsing the respective
XMLs and respective results are populated in respective "
template factories. JcodeGenerator uses these results and the
parsed formula results to generate the code.
tion Flle
3.1.3 XML Document Parser
As explained' earlier, the respective parsers viz.
Math Rules, JavaDoc generation rules, control Structures roles
are collected by parsing the respective XMLs and respective
results are populated in respective template factories.
JcodeGenentor uses these results and the parsed formula
results to generate the code.
Deriwi class
Output Base class
ClIS ••
Souree Co.
Co
a.,
Sowrce
3.1.4 Template Factory
Compiler
The Template Factory is the collection of XML
Templates used for generation of the code. By parsing
xmls, the respective factory data objects are populated
used while code generation.
,--- ---I
I Executable
I
I
I
Figure I: Partbl Oat. Generamr (5)
4. System Design Features
---------
Design patterns are about design and interaction of
objects as well as providing a communication platform
concerning elegant, reusable solutions to commonly
encountered programming challenges
3.1 System Architecture
XML
4.1 Singleton pattern
DOC1UlleJlt
RuaeraJld
A class of which only a single instance can exist
Whenever a user start ExCG and create an instance generating
the code, the same instance should be used further as same
generated code is required to be tested for the in puts provided
by the user. Due to the above requirement, ExCG uses a
singleton and processes the generated code with only one
instance.
Template
P
~.
Parser and
FOrlllula
er
Rule
4.2 Adapter pattern
Adapter classes convert the interface of a class into
another interface clients expect In future, the user can
generate code in multiple languages. In this situation, the user
can directly plug in a already written code which parser'
defined language roles (e.g. C++). In this scenario, the \,...",(
has to write only an adapter and plug in the already written
code and populate the factory objects.
Temph.1r:
Factory
._--
---,
I E:xecutable
L
4.3 Facade pattern
II
FJgUe 2: F.xCGAxeJd~ture
3.1.1 Formula Generator
The formula for which the code is required to be
generated is parsed and validated against the defined grammar
rules. In case of any exception, exception is handled by using
Parse Exception. For parsing the formula and populate the
data structures, parse Token Manager, Token, char stream etc
are used and data is populated in grammar data.
Facade provide an unified interface to a set of
interfaces in a sub system. Facade defines a higher-level
interface that makes the sub system easier to use. In this
situation, the user wants generate and test the code for the
formula Due to which its necessary to provide an interface
which interacts with the sub systems (Formula parsing, XML
parsing, Code generation etc) and provides the user the
generated code.
5. User Interface Design
The user interface (figure 3) shows command
hierarchy that defines following major system menu
categories. The menu bar, the tool palette and all sub ~
135
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International Conference on Systemics, Cybernetics and Informatics
Text box is provided to build an expression. Make use of
SYmbolview to choose numbers, operators and functions.
Note that whole expression must be equated to "-C. To reset
the expression Usee can use "Undo" button.
functions. The GUI contains the button hierarchy as: to enter
the mathematical formula. update, save and undo the changes.
The tool bar contains the icons for code generation, edition,
save, and test the developed code. The menu bar contains the
operation as code generation, edition, save, and test the
developed code. Middle window is reserved to display the
JAVA code generated for specified mathematical expression.
Lower window is used to display messages, exceptions, and
evaluation of execution results.
.
6.2 Code Generation
User must provide valid expression in the expression
view and pressing "Generate "button code will get generated
in the code view. Generated code is editable in the code view
that is user can modify the generated code as per his coding
stan
co, cut and aste wherever wants
__
m
m;«jM.lIlc.l4i:bl;
i!n;:orljMJ4.~
C1aSSJj~si:lIi'irser
, f
, lIl'.i.tdoiAllt(
:l jlJt~:5oubIe~ss;orJl:M(,~o,~
••,.:lkb._l,dout.s.dOol>e,,~;Jo;e~
5"
1 do'~
j
STllP.~~
gelcosW(l5.Gj;
:'U~.
STDRIIr.!\'8 gelsrt/a:(J).
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acutle~~
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Figure :Ex-CG GUI
;
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s:
~3PfR.~II;I>.W4~.cwl5l;
d.:lI.'II~STDRWn'ilE: fII3inY;~.5.m:
... =-~.==,=,~-=--=.=
.. ==~
The rightmost window is used to initialize the variables in
order to test the generated JA VA code.
.~~~~=
6. Using Ex-CG
6.3 Verification
The design of Ex-CG is founded on flexibility. It
can serve small organization intent on having quality coding
practices consistently
implemented throughout
the
organization. Improved coding practices will be quickly
propagated and will stay with the organization even if star
programmershave
left.
Knowledge
stays
and
accumulateswith the orgaaization, neatly encapsulated in the
template library.
To run the generated code use "Test" button. Code
will get executed for user defined values of variables in the
variable view and corresponding output will get displayed in
=.
=.
Figure 5: Expression View
oftbe developed code
~~~J;;::;l'Bft%~~Jdm§?4'f%tw@;¥fW¥'''':-:''''< ="9
~[valuat:incr
the e.nte"ion.. ..
~Re:sU1C ot ["re,.dOD
tor aivlI!%lvalue!!! : 7S617.7ZHi9299243
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j
l
"
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:j
1
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~
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,
...
,_,
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Figure 4: Message View
7. Benefits
7.1 Measurable
Productivity
Gains
Generating code by definition is always going to be
much faster than hand coding. The productivity gain when
writing the mathematical code is at least 70"10, with the coding
part of the design,code, and test cycle eliminated
7.2 Higber Quality
Generated code is error free and well designed
Development teams are more consistent Automatic code
generation ensures that software developers are more likely to
be focused on the business requirements than the more
mundane task of coding.
Figure 4: Expression View
/'
136
Automated Code Generation using Generative Programming Approach for a Mathematical Expression
7.3 Lower Maintenance Costs
9. References
The code generated by Ex-COG will be very easy to
understand and therefore easier to maintain. The true longtenn value of code generation emerges when there are new
business requirements. Ongoing maintenance costs are
reduced because it is easier to regenerate code than to make
manual code changes
•
•
•
8. Conclusion
The system can take place as a plug-in component
It simplifies coding to those developers who are frequently
racing mathematical expressions. Thus helping them to do the
best of actual problem.
•
The
xJen
Architecture
by
Michel . Katz
(http://www.codegeneration.netltiki-re8(Carticle.php?
articleId=32)
Generative and Component-Based Software Engineering
(http://www-ia.tuiimenau.deJ-czarnlgenerateJengi.html)
Generative Programming: Modem Techniques to
Automate Repetitive Programming Tasks: MSDN
Magazine, December 2001.
Generative Programming - Methods, Tools, and
Applications by Krzysztof Czarnecki and Ulrich W.
Eisenecker(http://www.generativeprogramming.org)€ode
Generator Model http://www.codegeneration.net/tikiindex.
~,
\
137