Transcript Aspect.NET – an aspect-oriented programming tool for Microsoft.NET Vladimir O. Safonov Professor of computer science, Head of laboratory St.

Aspect.NET – an aspect-oriented
programming tool for
Microsoft.NET
Vladimir O. Safonov
Professor of computer science,
Head of laboratory
St. Petersburg University
[email protected]
Aspect.NET project
(granted by MSR in 2002 and 2004)
Goals:
 Develop a state-of-the-art aspect-oriented programming
(AOP) tool for Microsoft.NET, on top of Microsoft
Phoenix, integrated with the latest Visual Studio (Whidbey)
and working also in SSCLI/Rotor environment
 Make AOP ubiquitous for Microsoft.NET software
developers
 Develop most adequate ways of representing aspects for
Microsoft.NET
 Lay the foundation for future research and development
work on spreading AOP among Microsoft.NET users
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
2
AOP origin and status
• Aspect-oriented programming (AOP) – a prospective
software engineering paradigm based on a concept of crosscutting concern whose implementation contains not only a
related set of modules (“generalized procedure”), but also a
set of tangled code fragments to be woven (inserted) into a
target application
• Predecessor: Professor A. L. Fouxman (Rostov University,
Russia), “Technological Aspects of Software Systems
Development”, 1979
• Modern classicist of AOP: Professor Gregor Kiczales,
University of British Columbia, Canada (AspectJ tool ~ AOP
extension for Java)
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
3
AOP basics
• Cross-cutting concern ~ a concern whose implementation cannot be
•
•
•
•
•
•
made by a generalized procedure
Examples ~ logging; security; MT-safety; implementation of a new
source language construct in a compiler
Aspect ~ implementation of a cross-cutting concern
Weaving ~ applying an aspect to a target application (inserting new
modules and definitions; inserting, replacing or deleting tangled pieces
of code)
Pointcut ~ a set of weaving rules for an aspect
Join points ~ a set of concrete points in a target application subject to
aspect weaving
Benefits of AOP: make software development and maintenance easier,
due to performing it in terms of aspects
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
4
Our approach to AOP
• Make aspects multi-language (language agnostic), in accordance to .NET
•
•
•
•
programming paradigm, as opposed to extending any concrete
programming language by AOP constructs (as in AspectJ)
Use a simple AOP meta-language Aspect.NET.ML to provide user-level
AOP annotations to source code of compilation units
Represent meta-information on aspects by custom attributes (AspectDef,
AspectRef), to safely tie them to assemblies, to make them easily available
to AOP tools, and to avoid updating any general .NET tools for the
purpose of their “AOP-awareness”
Use Phoenix to handle assemblies and to support weaving
Develop Aspect.NET as a Whidbey add-in to closely integrate it to
Microsoft.NET development tools, technologies and environments
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
5
Compare to other approaches to AOP
• Language extensions of a specific (usually – Java)
•
•
•
•
•
•
language for AOP (AspectJ)
Multi-dimensional separations of concerns (IBM HyperJ)
Interceptors
XML files with AspectJ-like specifications (Weave.NET)
Dynamic aspects (similar to debugger breakpoints)
Our approach is easy-to-use, language-agnostic, and
integrated with the latest Microsoft technologies and tools
(Whidbey and Phoenix)
As far as we can judge, right now there is no other AOP
tool so closely integrated to Microsoft development tools
as our Aspect.NET
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
6
Aspect.NET architecture
•
•
•
•
•
Aspect.NET.ML converters (currently for C#) to
definitions of AspectDef AOP attribute
Aspect weaver:
Target assembly + Aspect assemblies -> Target assembly*
Aspect editor + aspect GUI: locating aspects, coloring
aspects, editing aspects, deleting aspects; integrated to
Whidbey as add-in
Aspect.NET .msi-based installer (checks where the
Phoenix RDK is located on your machine)
AspectRotor – a separate console version of Aspect.NET
for Rotor environment
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
7
Example: the Politeness aspect
%aspect Politeness
public class Politeness
{
%modules
public static SayHello ()
{
System.Console.WriteLine(“Hello”);
}
public static SayBye ()
{
System.Console.WriteLine(“Bye”);
}
%rules
%before %call *
%action public static void SayHelloAction
{ Politeness.SayHello()}
%after %call *
%action public static void SayByeAction { Politeness.SayBye()}
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
8
Example: Weaving Politeness
%to MyApplication %apply Politeness
(the same can be done by means of Aspect editor)
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
9
Aspect.NET working screenshot
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
10
Aspect coloring screenshot
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
11
Aspect.NET status and perspectives
• Aspect.NET implementation team (SPBU PhD and graduate
•
•
•
•
•
•
students: Dmitry Grigoryev, Mikhail Gratchev, Alexander
Maslennikov, Oleg Romashin.)
A working prototype of Aspect.NET on top of latest Phoenix
(02/28/05) and Whidbey beta2 developed
Aspect.NET installer/distribution developed
Working console version of Aspect.NET for Rotor environment
(AspectRotor) developed
Aspect.NET uploaded to MSDNAA Curriculum Repository Web
site
Perspectives: library of examples; further research on aspectoriented knowledge management and on aspectizing (aspect
mining)
Our desire is to get funding from Microsoft to continue our
project, to make Aspect.NET a product to be shipped with the
future versions of Visual Studio.NET
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
12
Conferences and seminars where
Aspect.NET project presented
• First MSR Rotor Workshop, Cambridge, July 2002
• Rotor Workshop, University of Pisa, Italy, April 2003
• Fault-tolerant Software and Hardware Systems Workshop,
•
•
•
•
•
Hasso-Plattner Institute, Potsdam, February 2004
Microsoft Academic Days, Moscow, April 2005
IEEE Regional Conference, St. Petersburg, May 2005
MSR Faculty Summit, Redmond, July 2005 (as part of the
Phoenix panel)
Now MSR Rotor Capstone Workshop, Redmond,
September 2005
Current plans (Sep 2005): submit a paper and talk on
Aspect.NET to the Fifth International AOSD Conference,
Bonn, Germany, March 2006 (the “classical” AOP
conference)
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
13
Aspect.NET users, evaluators and those
who sent feedback (Sep 2005)
• Microsoft Phoenix team –
•
•
•


John Lefor, Shahrokh Mortazavi, Jim Hogg et al.
Mercury Interactive (www.mercury.com),
contact person: Yaniv Bronstein
University in Brazil, contact person: Andrea Furtado
Highly appreciated the project (email feedback):
Andreas Mauer, TRIA IT-consulting GmbH
(www.tria.de)
John Fahring [email protected]
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
14
Aspect.NET team’s creative contacts
to other AOP R&D teams
• Gregor Kiczales, University of British Columbia
• Andreas Polze, Hasso-Plattner Institute, Potsdam, Germany
• Mark Eaddy, Professor A. Aho’s AOP intern in Phoenix
team
• Donal Lafferty, Trinity College, Dublin, Ireland
(Weave.NET project)
• Tihamer Levendovsky, Budapest Technical University,
Hungary
• Andrea Furtado, University in Brazil
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
15
Aspect.NET references
1) http://aosd.net - The starting Web site on AOP
2) http://www.msdnaa.net/curriculum/?6219 – Aspect.NET&doc
3) Safonov V. O. Aspect.NET: a new approach to aspect-oriented
4)
5)
6)
programming. - .NET Developer’s Journal, 2003, #4.
Safonov V.O. Aspect.NET: concepts and architecture. - .NET
Developer’s Journal, 2004, #10.
Safonov V.O., Grigoryev D.A. Aspect.NET: aspect-oriented
programming for Microsoft.NET in practice. - .NET
Developer’s Journal, 2005, # 7.
Safonov V.O., Grigoryev D.A. Aspect.NET – an aspectoriented programming tool for Microsoft.NET. – Proceedings
of St. Petersburg Regional IEEE conference, St. Petersburg,
May 2005.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
16
Using Aspect.NET
Vladimir O. Safonov
Professor
St. Petersburg University
Installing Aspect.NET
Pre-requisites:
• 1) Microsoft Visual Studio 2005 beta 2 installed.
• 2) Microsoft Phoenix RDK 02/28/05 Release installed
Notes:
• Aspect.NET Framework has been tested under Microsoft
•
•
Visual Studio 2005 beta 2 and with assemblies written in
C# only.
To install Aspect.NET, run AspectNETFramework.msi
and follow tips of the wizard.
The installer copies core assemblies, deployment files as
well as Phoenix binaries into the folder specified by the
user.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
18
Starting Aspect.NET Framework
• The Aspect.NET Framework add-in window appears every
time Visual Studio is started.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
19
How to create an aspect in Aspect.NET ML?
•
•
Aspect is a special VS C# project template.
So, please create a new project (say MAddNopCounter) specified with aspect template.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
20
How to create an aspect?
•
•
The wizard generates the simple aspect skeleton in aspect.an file, which is container for
aspect description written in Aspect.NET ML.
Сode the body of the aspect in the .an file, based on the skeleton generated by the
wizard.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
21
How to create an aspect?
• Click “Build Solution” button or execute
“Rebuild All”. At this phase, the aspect.an.cs file
is created to contain correct C# source code with
ML annotations converted into the custom
attribute AspectDef. Then, the standard C#
compiler compiles it to the aspect assembly and
places it into the debug folder (say
MAddNopCounter.dll).
• One can weave this assembly as an aspect to
his/her projects.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
22
Weaving aspects
• Open or Create new C# project in Visual Studio.
• In Aspect.NET Framework click "Add Existing
Aspect Module" button on "Modules" tab to add
Aspect assemblies. You can add multiple
assemblies.
• Press "Find Joinpoints" button to find the join
points in the currently active project.
• If join points have been found, Aspect.NET
Framework switches to the "Aspects" tab. Here
you can filter the joinpoints and browse them.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
23
Weaving aspects
• Use the checkboxes in the join points tree to enable or
disable a join point. You can enable or disable groups of
join points by checking or unchecking parent methods,
classes and namespaces.
• You can click the join point to see its location in a source
code.
• Pressing "Weave Aspects" button results in aspects
weaving into the debug assembly of the current project.
• When weaving is finished , Aspect.NET Framework
informs you where the target assembly is located.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
24
Weaving aspects
• Visualization Tab represents program modules, with aspect actions
woven, as colored chart.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
25
Example of Weaving
• MAddNop is a basic sample included into
Phoenix RDK to demonstrate its capabilities. It is
a simple managed Phoenix based application to
add nop's to an existing executable.
• Let’s change its behavior without touching source
code and create an aspect MAddNopCounter to
add some tracing.
• The aspect reports on starting Phoenix
initialization process, prints Phoenix configuration
state and counts the number of nop’s inserted to an
executable.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
26
Step by Step playing with
Aspect.NET
• Turn the MAddNop.cs file from
\PhoenixRDK\src\Samples\maddnop into
VS project named MAddNop.
• Lets weave our aspect to MAddNop project
and check the results.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
27
Step by Step playing with Aspect.NET
• First of all load the source project into VS IDE.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
28
Step by Step playing with Aspect.NET
• Load the MAddNopCounter assembly to the Aspects list.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
29
Step by Step playing with Aspect.NET
• Click “Find Joinpoints” button and wait until the obtained points will
not be printed at Aspects tab.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
30
Step by Step playing with Aspect.NET
• To weave the actions to the join points, click “Weave Aspects” button and
•
•
check the resulting assembly ~MAddNop.exe in the debug folder of your
project.
Lets try how it works on the testapp.exe shipped with PhoenixRDK. Copy
testapp.exe and testapp.pdb from \PhoenixRDK\Applications\Tests into debug
folder of MAddNop project.
Run “~MAddNop.exe testapp.exe newapp.exe”
and “MAddNop.exe testapp.exe newapp.exe”
in the console to compare the behavior of the assembly with the aspect woven
to that of the original assembly.
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
31
Step by Step playing with Aspect.NET
• The result of executing two assemblies is presented below.
• As we can see, output of our new assembly is much more
informative, as compared to the original assembly. No
Phoenix source code touched to achieve this goal
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
32
AspectRotor
• The first Aspect.NET console version working in the Rotor
•
•
•
•
environment. Included into the Aspect.NET archive
uploaded to the MSDNAA Web site
A set of Perl scripts (please use ActivePearl 5.8.7) to
initialize, to build and remember target applications and
aspects, to select join points, to visualize the sources, to
weave aspects, to run the original and the updated
assemblies
Uses Phoenix as well-as the add-in version, and the Rotor
binaries shipped with the Phoenix RDK
A simple comfortable menus in console mode provided for
each step; it’s possible to undo and return back
DEMO (IF TIME PERMITS…)
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
33
Q&A
Vladimir Safonov, SSCLI Capstone
Workshop, Redmond 2005
34