Remote web interface to a Java Application

[Sheetal Khemani]

If I have a Java application running on a server, is there some Java
technology by which I can remotely access/modify the memory of that
application ?

Basically, I need to write an interface, preferably within a web
browser, that can remotely access/modify memory of an application
running on a remote server.

Any input is appreciated.

Thanks
Sheetal

 

[Andrew Thompson]

If I have a Java application running on a server,

Do you control the application on the server?
Did you write it?

..is there some Java
technology by which I can remotely access/modify the memory of that
application ?

What *exactly* do you mean by that?
Perhaps it is better to state what you want to *achieve*
than what you want to *do*. So, what do you hope to gain
through this 'memory modification'?

Basically, I need to write an interface, preferably within a web
browser, that can remotely access/modify memory of an application
running on a remote server.

Again you state what you want to *do*, rather than what
you are trying to achieve.

Any input is appreciated.

There are probably a number of ways to achieve the end
result you are after, but that depends on what that
'end result' is. Back to you.

 

[Sheetal Khemani]

Do you control the application on the server?
Did you write it?


What *exactly* do you mean by that?
Perhaps it is better to state what you want to *achieve*
than what you want to *do*. So, what do you hope to gain
through this 'memory modification'?

The application consists of a complex schedule, that I am yet to
write. I control everything about this application. The application
sits on some server on the web.

I need ways to interface into this application via the web browser to
do two things:

a) I need to be able to run an algorithm on this schedule.
b) I need to be able to modify the schedule within the application.

I am investigating the easiest way to design/implement this.

I know I could save the schedule in a database, and have an html
frontend. I can map the html requests to operations on the schedule.
Everytime someone modifys it I can update the database. Also if I need
to run the algorithm on it, I can load the database into memory (build
the schedule), run the algorithm, return the result in html.

What I am wondering is, can I skip the need of a database, store the
schedule prepetually in memory - and have java applets (or something
similar?) that can directly access the memory of the application ?
This would help me skip the whole html part too.

I don't know if this is possible, it's just a thought I'd like to
investigate. What got me thinking along these lines, is that in Unix
we can define shared memory across processes; this would be similar
only the memory would be shared across processes on seperate machines.

 

[Andrew Thompson]

The application consists of a complex schedule, that I am yet to
write. I control everything about this application. The application
sits on some server on the web. ....
I am investigating the easiest way to design/implement this.

The *easiest* way is not always the best..

I know I could save the schedule in a database, and have an html
frontend.

That is part of the best way.

The best way to do this is to offer a rich client front end
to a D/B, that degrades cleanly (for those with no Java in
the UA they are using) to HTML.

What I am wondering is, can I skip the need of a database,

If your app needs a D/B, use a D/B..

..store the schedule prepetually in memory -

....you must be kidding. What happens when the JVM
is dropped by some process you have no control over?
All your data is lost.

At the very least write it as XML objects to a safe place
on the server. But then, that brings us back to the form
of the data storage and processing and that (sorting,
filtering, updating) is something a D/B is specialised to do.

...and have java applets (or something
similar?) that can directly access the memory of the application ?
This would help me skip the whole html part too.

No - you need that even when you have the applets.

I don't know if this is possible,

Possible, probably. Sensible, no.

...it's just a thought I'd like to
investigate. What got me thinking along these lines, is that in Unix
we can define shared memory across processes; this would be similar
only the memory would be shared across processes on seperate machines.

Java does not allow this level of memory 'sharing', but the
classes of an applet could communicate witha Java application
on the server in various ways in order to make it change
the state of attributes it owns or has access to.

That is not the way I would recomend designing this web-app. though.

 

[Sheetal Khemani]

Java does not allow this level of memory 'sharing', but the
classes of an applet could communicate witha Java application
on the server in various ways in order to make it change
the state of attributes it owns or has access to.

This is what I am interested in. I want to investigate this further
before crossing it out.

How does a Java applet communicate with a remotely running Java
application ? What protocol is used for this communication and how is
data transferred across (xml?) ? Could you point me to some documentation
on how this is done.

Thanks
Sheetal

 

[Michael Borgwardt]

This is what I am interested in. I want to investigate this further
before crossing it out.

How does a Java applet communicate with a remotely running Java
application ? What protocol is used for this communication and how is
data transferred across (xml?) ? Could you point me to some documentation
on how this is done.

If both sides are Java, this would usually be done with RMI:
http://java.sun.com/docs/books/tutorial/rmi/index.html

 

[Andrew Thompson]

On Mon, 08 Nov 2004 19:39:49 -0000, Sheetal Khemani wrote:

(A.T.)
Such as a D/B written in Java.

One of which is exactly the same way a pure HTML interface
might interact witht the D/B. Doing a post/get call to a
..JSP/Servlet that connects to the D/B.

This is what I am interested in. I want to investigate this further
before crossing it out. ....
How does a Java applet communicate with a remotely running Java
application ?

Various ways, URL, sockets, RMI..

..What protocol is used for this communication

Depends on the data. There are a multitude of possibilities.