1. Microsoft.NET Vs Sun JAVABY
S.Kartikeyan

2. MOTTO Microsoft.NET Software to Connect Information,
People,Systems and Devices
Bill Gates
JAVA
Write Once ,Run Anywhere
Bill Joy

3. DESIGN GOAL Classic Application .NET Application Your Application
Windows OS
Scanner
.NET Framework
Internet
Devices
Monitor
Keyboard
Mouse
Cell
Laptop
Palmtop
(Contd…)

4. Microsoft Operating Systems
Java Applications
.NET Applications
JVM
JVM
JVM
.NET Framework
Microsoft Operating Systems
Win2000,WinServer2003,
Windows XP
Win OS
Linux
Apple
Hard
Ware
Hard
Ware
Hard
Ware
Hardware

5. Why is .NET Microsoft Wanted an alternative to maintain different
libraries being written for VC++,VB,ASP etc.
Address Emergence of XML and Web Services
Provide Something New
Compete with JAVA world by providing free compilers
Integrate all this in the next version of Visual Studio

6. Myths About C# ,.NET and Java
Microsoft.NET is a Platform and C# is a language
on it just like C is for UNIX.There are many other
language on .NET like VB,VC++
When people talk about Java they don’t
know whether they mean Java Language
or Java Compiler or Java Virtual Machine

7. Different Levels and Terminology
Language Level Distinguishing C# and Java features
Compiling level How to locate the libraries and other
dependencies
Runtime Level CLR Vs JVM and Runtime Libraries
At a developer level what are the differences
At the Enterprise Level what differences can be noticed
Finally what does the End User get out of both
Future of both the technologies
Managed Exe or Dll means that which are run by
Common Language Runtime of .NET(mscoree.dll)

8. Language Level James Gosling
Java is called a better C++ though some of the useful features
like operating overloading was removed for no clear reasons
C# retains all the good features of C++ including operator
overloading
Pointers considered the most useful feature and dangerous feature
of C++ is completely removed in Java
C# has a special block called unsafe{}. You have to use pointers
only in these blocks.
C# provides all security access levels of the code which Java
provides

9. C# switch statement is more matured than Java switch statement
which Java designers call themselves NONSENSE C SWITCH SYNTAX
Class files in Java are similar to C# Managed Dlls
Jar files in Java which are usually collection of class files
such as servlet.jar are somewhat similar to .NET asp_net.dll
C# is object and component oriented where as Java is object
oriented. To support component oriented programming C# supports
adding attributes to types which will be understood by compiler to
generate corresponding IL code. C# dll’s or exes (managed) can call
COM components and COM components can call C# Dll’s and exec's.
That is contrary to Java where it uses a package called beans
Example of attributes
[STAThread]
public static void Main(){}
Java applets has no C# equivalent. So writing Java Browser plugins
is more easier than C# components ( ActiveX controls)

10. Compiler Level Source Files Libraries C:\winnt\GAC Source Files
Compile Time
Libraries
C:\jdk\lib
CSC
JAVAC
XYZ.dll Or
XYZ.exe
XYZ.class

11. Runtime Java Virtual Machine is called java.exe
JVM understands byte codes in class files
Runtime libraries exist in JRE directory
Running a program or class file is shell:>java.exe xyz
Java.exe calls xyz.Main()
Applies some permission objects and policy files and runs xyz in a sandbox
.NET Virtual Machine is mscoree.dll
It is also called common language runtime (CLR)
JVM understands MSIL in dlls and executable files
Runtime libraries exist in C:\winnt\GAC
Running a program is just shell:\>xyz.exe no explicit invocation of CLR
CLR calls the xyz.Main()
Applies some permission objects and config files and runs xyz in a sandbox

12. Loading of CLR in Managed exe
C# compiler places
JMP _CORExeMain in CODE Section
mscoree.dll in IDATA section of abc.exe(say)
In Unix to know the .so files a exe refers try sh:>ldd /bin/bash
You invoke abc.exe from a shell in the case of Managed exe
Windows Loader checks the IDATA section and attaches
Mscoree.dll to the process address space.
Then it fixes the _CORExeMain function address in CODE Section .
The _CORExeMain function does the invocation of JITCompiler
Which translates MSIL to Native.
Native code then executes

13. Loading of CLR in Managed Dll
In the case of Managed dll being loaded at runtime you typically
Use LoadLibrary() Method passing the name of the Managed dll file
Windows Loader calls the DllMain() function of the Managed dll
DllMain() Loads MSCorEE.dll
DllMain() of MSCorEE.dll calls _CORDllMain() function
_CORDllMain performs all the tasks what _CORExeMain does
The _CORDllMain function does the invocation of JITCompiler
JITCompiler translates MSIL to Native.
Native code then executes

14. Developer Level
In Java you have no option than to program in JAVA language
In .NET there are some 10 languages as of now ,of which the
prominent one is C#.
All Language compilers compile their code to MSIL
This is possible as all adhere to the Common Type System(CTS) of .NET
Visual Studio.NET IDE is better than any JAVA IDE available today
It can be possible in JAVA if someone writes a new language compiler
in for JVM which translates sources files to JVM compatible class files
Users in .NET now has the option of having any language to generate
a library and it can be reused from any language

15. Enterprise Level Presentation Tier (ASP.NET Vs JSP) Middle Tier
( Web Services, DCOM Vs
Web Services and Beans)
ADO.NET
JDBC
Database Tier(SQL Server Vs ____)

16. End User Level Microsoft.NET Passport is one of the services end-users
are getting advantage as of now
More are expected to come

17. Future and Marketing Elements
Microsoft has good Marketing expertise than SUN
Visual Studio.NET IDE is an added advantage to Microsoft
Java world has to wait for such an IDE
Microsoft is spending a lot of money in .Net R&D
On the other hand IBM is spending 10 times more than SUN
to promote JAVA .
The support for XML in Microsoft.Net is Fundamental where is in JAVA
it is an API based
As Microsoft.Net and Java support XML Web Services ,developers
has the choice of either platforms

18. Thank You