Download Slide 0

Quality Assessment of
Xtend Model Transformations
Phu H. Nguyen, h.p.nguyen@student.tue.nl
Supervisor:
Tutor:
Prof. dr. Mark van den Brand
Ir. Marcel van Amstel
Agenda
•
•
•
•
•
•
•
•
Introduction
Project goal
Overview of Xtend model transformations
Metrics
How to extract data from Xtend model transformations
Tools
Case studies
Conclusions
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 1
Introduction
• Model Driven Software Development (MDSD): the next
level of software development
• High level design models at the heart of the development
process
• Software development automation
• Benefits : Productivity, agility, reliability
• MDSD world:
• Domain-specific languages (DSL)
• Model transformations M2M (Model-to-Model)
• Model transformations M2T (Model-to-Text)
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 2
How MDSD works
M2M : Transform models to models
• ATL - the Atlas Transformation Language
• QVT (Operational) - An implementation of OMG’s spec.
• Xtend – openArchitechtureWare (oAW) ’s transformation
language (also used for other tasks within oAW)
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 4
Model transformations M2M
• Is there a methodology for developing model
transformations with high quality?
• Need of assessing the quality of model transformations
• Quality assessment of model transformations:
•
•
•
•
ASF+SDF: enabled
ATL: enabled
QVT: ?
Xtend: ?
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 5
Project goal
• The main goal is to enable quality assessment for Xtend
model transformations by means of metrics.
• Approach: assessing the internal quality of model
transformations by extracting metrics from the model
transformations directly.
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 6
Sub-goals
• Four sub-goals:
• Discover the details behind Xtend model
transformations.
• Establish a metrics suite enables quality
measurement of Xtend model transformations.
• Develop a tool that enables automatic calculation of
those metrics.
• Perform case studies to validate the results.
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 7
oAW & Xtend model transformations
• An integrated, tested, one-stop toolkit for MDSD
• oAW essentially makes it possible to process code
generators for any type of model.
• Any type of source code can be generated from the
model sources.
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 8
Features of oAW
• The most important features of oAW include:
•
•
•
•
•
support of various modeling tools
support of EMF (Eclipse Modeling Framework)
model-to-model transformations
model-to-code-transformations
eclipse integration
• Migrated to Eclipse:
• http://www.eclipse.org/workinggroups/oaw/
− Xpand/Xtend/Check
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 9
oAW components
•
•
•
•
•
•
•
Metamodel definition: EMF, UML model
Graphical model editor: Eclipse GMF
Textual model editor: Xtext
Model transformation: Xtend
Model validation: Check
Code generation: Xpand
Metamodel extension: Xtext
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 10
Xtend model transformations in oAW
Xtend
• OCL-like expression language used throughout oAW
• Can be used in constraint checks, model transformations
and generators
• Add “methods” to meta types (Java calls are possible if
necessary)
• path expressions, set operations, (some) higher order
functions
• Polymorphism (multiple dispatch)
• Tool support
(syntax highlighting, code completion, debugger)
Xtend model transformations…
… are defined in extension files (*.ext):
• Import statements
• Import name spaces (meta-models)
• Import (reexport) built-in libraries or another extend files
• Create extensions
• Expression extensions
• Java extensions
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 13
Xtend model transformations
Xtend has some special support for M2M transformations
• Create-Extensions are used to create a new instance
• A new element is created only once for the same set of
parameters
• Cached Extension can be used for perfomence
improvements
• The same value is returned each time the extension is
called with the same set of parameters
• Several utility extensions (built-in libraries) for naming,
tracing, debugging, cloning, …
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 14
Book → Publication
• Rules to transform a Book model to a Publication model:
• Each Book instance → a Publication instance
• The title of a Book → the title of a Publication
• The total number of pages of a Publication is the sum of the
pages of the Chapters of a Book.
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 15
Book → Publication
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 16
Book → Publication: Extension File
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 17
Metrics for Xtend model transformations
• A set of metrics has been proposed for enabling quality
assessment of Xtend model transformations
• These metrics are specific for Xtend
• Metric categories:
• Extension metrics
• Dependency metrics
• Other metrics
• Two types of metric:
• Metrics that are measured over the entire transformation
• Metrics that are measured on a smaller scale (per extension
file, per extension…
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 18
Metrics for Xtend model transformations
Extension metrics
• # Extensions
• # Create/Expression/Java Extensions
• # Private/Public/Cached Extensions
•
•
•
•
•
•
•
# Extensions per Extension File
# Extensions with Parameter
# Overloaded Extensions
# Parameters per Extension
# Unused Parameters per Extension
Cyclomatic Complexity per Extension
…
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 19
Metrics for Xtend model transformations
Dependency metrics
• # Imported Standard Libraries per Extension File
• # Imported Extension Files per Extension File
• # Calls to Extensions in Standard Libraries per Extension
• # Extension Calls per Extension
• # Internal Extension Calls per Extension
• # External Extension Calls per Extension
• # Usages per Extension
• …
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 20
Metrics for Xtend model transformations
Other metrics
• # Extension Files
• # Imported Namespaces (Metamodels) per Extension
File
• # Arounds
• # Checks
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 21
How the XtendParser works
• The XtendParser constructs an Abstract Syntax Tree
while parsing an Xtend file.
• The transformation functions after parsing *.ext files are
represented as an in-memory model consisting of
POJO’s (Plain Old Java Objects).
• The basic type is
org.eclipse.internal.xtend.expression.ast.SyntaxElement
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 22
Xtend AST
Metric Extractor Tools
• Design requirements
• Input: Extension files
• Output: Metrics
− New metrics can be defined easily
− It is possible to quickly implement the calculation of a new
metric
Metric Extractor Tools
• In order to calculate the metrics, we need to extract data
from the Xtend AST(s) to store in a well defined data
model
• “data” means all elements of Xtend model transformations
• A well defined data model = data can be stored easily and
metrics can be calculated easily.
Metric Extractor Tools
• Which data model?
• Relational data model: No
• Java Objects
− Store data easily: The Xtend AST consists of Java
Objects
− Easily implementing metrics calculation in Java
• XML
− Store data of the Xtend AST in XML
− Easily calculating metrics by using Xpath, Xquery
Metric Extractor Tool 1 – M2M QA
• Data model = Java Objects
Class diagram of Java objects
Class diagram of Data Extractor
Simple Metrics
Aggregate Metrics
GUI for M2M QA
• Implement GUI, as a jar file
• Implement as an Eclipse plugin
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 32
Metric Extractor Tool 2
•
•
•
•
Data model = XML
Native XML database eXist
XPath and XQuery are used for querying the XML data
GUI: A web application
• Java, JavaBeans, JSP/Servlet and Java Server Faces.
• Apache HTTP server Apache Tomcat 7.0.
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 33
Metric Extractor Tool 2
DTD
<!ELEMENT xtendPrj (extendFile*)>
<!ATTLIST xtendPrj prjName CDATA #REQUIRED>
<!ATTLIST xtendPrj prjDir CDATA #REQUIRED>
<!ATTLIST xtendPrj rootExtFile CDATA #REQUIRED>
<!ELEMENT extendFile (importedNamespaces|importedExtFiles|extensions|arounds|checks)*>
<!ATTLIST extendFile extFileName CDATA #REQUIRED>
<!ELEMENT importedNamespaces (namespace*)>
<!ELEMENT namespace (#PCDATA)>
<!ELEMENT importedExtFiles (extFileName*)>
<!ELEMENT extFileName (#PCDATA)>
<!ATTLIST extFileName reexported CDATA #REQUIRED>
<!ELEMENT extensions (extension*)>
<!ELEMENT extension (extName|qualifiedName|parameters|returnType|extBody)*>
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 35
XML
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xtendPrj SYSTEM "xtendPrj.dtd">
<xtendPrj prjName="" prjDir="../my.slco.project/src/"
rootExtFile="../my.slco.project/src/slco2nqx/Bi2Uni.ext">
<extendFile
extFileName="../my.slco.project/src/slco2nqx/Bi2Uni.ext">
<importedNamespaces>
<namespace>slco</namespace>
<namespace>channels</namespace>
</importedNamespaces>
<importedExtFiles>
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 36
Xpath, XQuery
# Extensions per Extension File: This metric counts the
number of extensions per extension file.
element { "result" }
{
for $extFile in doc("xtendM2M/Bi2Uni.xml")//extendFile
return
element { "extCountPerExtFile" }
{
count(for $ext in $extFile//extension
return $ext)
}
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 37
M2M QA Web Application
•
•
•
•
•
Upload (zipped) extend files of an Xtend project
Browse data
Metrics calculation
Search
Download reports
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 38
M2M QA Web Application
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 39
Summary
• A set of metrics has been established to enabling quality
assessment of Xtend model transformations
• Extension file(s) are parsed by the XtendParser to get
the corresponding AST(s)
• 2 types of data model => 2 tools
• All the metrics can be automatically calculated by these
two tools
• The results extracted from both tools are the same
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 40
The end.
/ Department of Mathematics and Computer Science
24-5-2017
PAGE 41