Java
to .NET – Migration Path
Host: Ajay Solanki – Consultant, Microsoft Consultancy Services,
India
August
7, 2002
KunalS_MS: Good afternoon all
KunalS_MS: Welcome to today's session of eXPerienceDotNet Chat session
KunalS_MS: Today's topic is Java to .NET - Migration Path
KunalS_MS: and our host of the day is - Ajay Solanki
KunalS_MS: Ajay is a Consultant at Microsoft Consultancy Services,
India
KunalS_MS: and a specialist on .NET development
KunalS_MS: And so now over to Ajay
Moderator: (mrinal) J2ee architecture is called highly stratified
, what about similar qualities in .net architecture
AJAYS_MS: What does stratified indicate here? Layered?
AJAYS_MS: Well J2EE and .NET follow the same Architecture
Pattern i.e 3- Tier / so all the 3 tiers have similar functionality
on the software to get functionality varies
Moderator: (mrinal) I actually want to know the key improvement /
changes that Microsoft has introduced
AJAYS_MS: The key improvement and changes are clearly
noted in the scalability features, programming model etc.
AJAYS_MS: .NET application VS Java Application of the
same nature example Pet Store the scalability numbers give a better
picture
AJAYS_MS: deployment and other standard features have
improved.
AJAYS_MS: Some of the key benefits of the .NET framework
from a developer perspective are…
AJAYS_MS: Supports multiple programming languages
AJAYS_MS: Type safety - No unsafe casts, no uninitialized
variables, no out-of-bounds array indexing
AJAYS_MS: Unified type system - Everything is an object,
no variants, one string type, all character data is Unicode
AJAYS_MS: Zero-impact install - Installing one application
will not affect another
AJAYS_MS: Side-by-side execution - Multiple versions
of the same component can co-exist, even in the same process
AJAYS_MS: No more plumbing to write - GUIDs, CLSIDs,
ProgIDs, HRESULTS, CoCreateInstance, IUnknown, BSTRs, Type Libraries,
IDL are now all history!
AJAYS_MS: Object system is built in, not bolted on. No
additional rules or API to learn.
AJAYS_MS: Enables clean OO programming Classes and Interfaces,
full polymorphism Properties, methods, events implementation inheritance
AJAYS_MS: Compare .NET http://www.microsoft.com/india/msdn/experiencedotnet/static/compare/compare.htm
will give you more information on the same
Moderator: (Sreejumon) What is the main difference between CLR and
Java Virtual macheine?
AJAYS_MS: to start with the internal components of a
CLR and JVM are totally different. The way I would see is JVM / ILM
is one of the parts of a CLR
AJAYS_MS: If I would to compare JVM / ILM the nature
of compilation varies totally
Moderator: (Ethan) Will JLCA final version support JDK 1.3 & 1.4?
AJAYS_MS: NOT decided as yet on this
Moderator: (Sreejumon) J2EE is a proven platform, with a few new web
services APIs. .NET is a rewrite and introduces risk as with any first-generation
technology. Please comment.
AJAYS_MS: If one looks at the J2EE architecture especially
the coding effort one spends in writing is very high, Usually at an
estimate it is about 1.8 times effort estimated to .NET project
AJAYS_MS: More over .NET is not a total rewrite let say
if you where migrating from earlier MS application to .NET you have
a phased -wise approach/ A total rewrite is ruled out here
AJAYS_MS: Well If I am migrating from Java to .NET then
it still remains phased wise
AJAYS_MS: As you see some clients may intend keeping
the EJB in place and may ony want ASP.NET to talk to EJB's or the
other way around
Moderator: (Sreejumon) .NET web services are not interoperable with
current industry standards. Their BizTalk framework has proprietary
SOAP extensions and does not support ebXML . Please Comment.
AJAYS_MS: There are no proprietary SOAP extensions firstly
AJAYS_MS: As regards to integrate with Biz Talk MS has
plans to come out with webservices adpater for Biz Talk
AJAYS_MS: Biztalk a lot other industry standard ISO 8583,
also shortly coming with adapters to support IFX and SWIFT
Moderator: (mrinal) what about jvm being compatible with several operating
systems and .NET not. doesn't it comes as a disadvantage of shifting
, as your already existing applications work on linux , windows ,
unix , mac , solaris Please comment.
AJAYS_MS: Although the line 'Write Once, Run anywhere'
looks good on paper, translating it into reality is a whole new ballgame.
The truth is that due to disparities in the underlying hardware, threading
architecture across platforms like Mac, Solaris any Java application
cannot be easily ported without adequate testing.
AJAYS_MS: Microsoft has submitted specifications of the
CLR, CLI to ECMA thus allowing third-party vendors to extend the .NET
framework for other platforms.
AJAYS_MS: There is already a version of the .NET framework
available for the UNIX platform developed by a third-party.
Moderator: (Sreejumon) In J2EE, they have entity beans and middle
tier database cache. What is the equivalent in .NET?
AJAYS_MS: There is no direct equivalent to an entity
bean in .NET where the component data is persisted in a relational
database.
AJAYS_MS: But the functionality of memory-level persistence
across object lifetimes can be achieved by the usage of Shared Property
Group Manager offered by COM+ .
AJAYS_MS: Strongly typed ADO.NET datasets also offer
a way of modeling objects like Customer, Order etc. and can be persisted
to the database.
Moderator: (Mrinal) There were some plans regarding getting perl under
.net framework , is there some progress regarding the same
AJAYS_MS: Third party vendors are developing add-ins
to enable developers to write code in Perl for the .NET platform.
E.g. http://aspn.activestate.com/ASPN/NET
Moderator: (Mrinal) can you suggest something regarding .net applicability
in field of telecommunications
AJAYS_MS: In this space, Microsoft offers products like
Mobile Information Server, Mobile Internet Toolkit etc. to assist
developers in the development of mobile applications.
AJAYS_MS: In addition, RTC (Real Time Communication)
is facilitated by products like Windows Messenger and RTC Server (to
be released).
