Those are three questions, but here are the answers.

1. Because it rocks
2. Because I rock
3. Everything.

Java is somewhat based on the structure of C++,  C++ is merely the C
language with a bunch of additions, such as classes.

Java was DESIGNED to use classes, java (mostly) automatically handles
garbage collection, java also takes out a piece of C++ that many
experienced developers still have trouble with after years and years of
programming, pointers.

I use java because for these reasons, in addition to the fact that java
is machine independant.  As long as the user has java installed (by
default it is installed by web browsers today), they should be able to
run my applet of application.  If I want to distrubute my application
on Mac, Linux and PC, I can even create an installation that installs
the runtime environment that I choose my application to run on.

I enjoy C++, java feels cleaner to program.  It beats VB, in my mind
because VB was designed for business people who wanted to do a little
programming, and now has been expanded more for the developers.  Plus
VB is a windows platform specific language, also requiring the version
of the vb libriaries installed on the machine for the application to
run.

Since Visual Basic and Visual C++ are windows based languages, they
also suck because I cannot deploy the same application on windows xp,
windows 2000, or windows 98, and I am absolutely positive that when
vista comes out, many applications will have to be redeveloped to
actually run on vista.

anyway when I think about what languages to write an application in,
those are the ones that come up,

applets are unique to java.  many times flash could do the job, but
hey, java does kick a.s.  Plus java allows you to have more control
over your application, instead of only being able to use a limited
number of objects to achieve your goal.

To fill in the hugest gap not mentioned.
Java is brilliant for distributed apps of all flavours.
RMI, RPC, Http Web Apps, Web Services, Corba, EJB managed transactions,
messaging protocols... you name it java has a library that exploits it.
Whats more so many people of an open source mind think so to that all there
work, and what fine work it is, is available for free for you to build on
top of.

--
Mike W

   why> i have only 2 question about Why java good for programing? or
   why> Why you chose The java for progrming?  and what application
   why> can do with java ?  thanks

You can do everything with it -- GUI, commandline applications and
web.  Of course, there are other things, like mobility packages
(phones etc) that are way beyond me.

It's object-oriented.  (Some people call it a "class" rather than an
"object" oriented language.  I don't know.)

It does what I want it to do.  Mostly.

It's everywhere.

You can get a lot done in a good IDE, too.  The financial impact of
becoming a productive programmer is minimal.

The one disadvantage I find with Java is that it's difficult to work
in machine-dependent areas.  An obvious one with which I have worked
is starting/stopping Windows services.

Thanks.

mp

Interoperability - In general Applications written will compile to bytecode
which will on  any environment which supports java.  (In the real world
there are some limiting factors like hardware - but not for simple
applications.)

Java is easy, and fun.  It is standardized so if you find example code on
the web, it will usually compile with little or no difficulty.   There are
tons of examples, and lots of help.   (This may to a certain extent be
because of the standardization and interoperability.)

There is a stigma that Java is slow.   In general this doesn't seem to be
much of a limiting factor - but some people still believe so.   Because of
the JVM, java apps will have a larger memory footprint, overhead and start
time.   You can overcome this by using a native compiler like Excelsior or
the GNU native java compiler (Linux only).   But if you do this, then you
lose interoperability.

The primary complaint I've heard about the language itself is that it is
verbose.  I think what people mean when they say this is that they are mad
that they have to deal with Exceptions that could be thrown - nothing
negative AFAIC.

--
LTP

I chose it because it is multiplatform.  This does two nice things:

1. it allows hardware to evolve to quite different architectures and
the code still runs.  If there is a large body of Java code, hardware
evolution should speed up.  It makes backward compatibility with
legacy chip designs less important.  The JVM also allows evolution of
new languages that can still exploit the Java class library.  The
evolution of computers is my top priority since I see it as the only
hope man has for sustainability.

2. Being multiplatform cauterises quirkiness.  The Java API is ever so
much more sensible and clean than any proprietary API.

You can use Java for pretty well everything now from a cell phone app
to a 256-CPU supercomputer number cruncher.  The main thing it cannot
do is device drivers.  The other thing it cannot do is interface with
proprietary features of the Windows API.  Even then a 90% Java program
with 10% JNI is simpler than going pure C.