Is it possible to run a normal java program in a servlet

Well anyone knoe and if so how is it done? Cheers

.> On my current project, a reporting component, we
do
in fact call a standalone program asychronouslyfrom
our Servlet. The one scaling requirement that is
dictating this is memory footprint. By using a
standalone application, I can set the amount ofheap
space the reporting component will be allowed touse.
Thusfar, it uses swap/virtual memory when that
t amount is exceeded, which is the intendedeffect:
increase processing time to save memory. Saish, if you're breaking the rule it's because you
have a good understanding and a good reason to do
so.
You said the magic word here: "asynchronous". I
totally agree that having your app send a message to
a MDB for asynch processing is appropriate. In this
case, it sounds like it's the only way to do it due
to the excessive memory requirement.
We have an app running in production that does
exactly that: send a message to an MDB to process
something off-line. The user is sent to a page to
continue their session while processing proceeds on
another thread, another machine.
It's the first time I've run into a memory scaling requirement like that. Our co-located facility only allows us '10% of CPU and no more then 128 mB'. So, to avoid crowding out other requests, we decided to calve the report process into an asynchronous, standalone application. I was kind of hoping we could do something slick with java.lang.ref to help with memory management, but the more I looked into it, the scarier it became!
When I read the OP's post it made me think that s/he
wanted to invoke Runtime.exec() to kick off a
synchronous process. If s/he comes back and says
that's the case, I'll stand by my answer. If they
say asynch is what they need, they should follow the
wisdom of Saish.
I agree. The OP probably does not have this type of requirement. In the vast majority of cases, Duffy is correct. You probably should re-think your design if another standalone process is being invoked.
PS - How's with you? I hope you and your family are
all well.
Doing great and had an awesome 4th o July weekend. Spent Saturday on a boat for seven hours. Though I look par-boiled today, it was a full-on treat.
How's by you? Any Independence Day ribaldry or chicanery? :^)
I've gotten through the AOP and JDBC chapters in "Pro
Spring". Now I'm off to read about Hibernate again.
Gotta be writing more code to truly master this,
, especially on the UI side.This weekend, I did not get much time to continue my trek through the vast landscape of Spring. However, this week, I am moving towards knowledge sharing and documentation tasks, so I should have some time after work to keep learning.
UI side? You mean Servlets/JSP/XSL? Or something more traditional like Swing?
BTW, now I remember why I hate coming into work on off days (aside from the obvious): they don't turn on the @#$! A/C. I'm dying here today!
- Saish

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[email protected]

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at java.lang.ClassLoader.loadClass(Unknown Source)
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Childofheinlein wrote:
I'm new to programming in general and java in specific. I am using the jGrasp programming software, and successfully compile my program, but when I try to run it out of DOS (which I undesrtand is the purpose of java to begin with, unless I'm mistaken), I get an exception that looks exactly like this.....
So summerizing some of what was said before and some of that wasn't.
jGrasp is a simplistic IDE. When you pop a dos window from it it sets up the windows correctly to run your program. When you open a regular command window you must do the same yourself.
>
Exception in thread "main" java.lang.NoClassDefFoundError: keyboard/javaJava runs "classes". The command that you typed above meant that you were trying to run a "file". Specifically the file "keyboard.java". The two are not the same. There is however a relationship. When the source code, in this case inside of "keyboard.java" is compiled it produces a file called "keyboard.class". Insided of the file there is a "class" called "keyboard". Notice that the name of the class does not have either .java nor .class on the end of it.
The VM (the 'java' command) finds a "class" using the class path to search files of various types for the class (again keep in mind that files contain classes but they are not themselves classes.)
You can add to the classpath using the Sun VM using either command line options or environment variables. As noted in some of the previous messages those are "-cp" and "CLASSPATH". It is important to note that that does NOT fully specify the class path. But for your purposes it is sufficient to think of it as doing so.
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java -cp . keyboard
java keyboard
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So if your class file has the following location: c:\myapps\java\keyboard.class then you can do the following.
1. Open a console window
2. Type "cd c:\myapps\java"
3. Type "java keyboard"
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Hello:
Learning Java.
I have Windows 7 64 bit. I have following Java installed:
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C:\Program Files\Java\jdk1.6.0_21\demo>
Will appreciate your early help. Thanks.
Victor

Recomplied and still no luck. I gave a different name to the program and still getting the same error as follows:
C:\Program Files\Java\jdk1.6.0_21\bin>dir hel*
Volume in drive C is WINDOWS7PRO
Volume Serial Number is EB0E-8900
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2 File(s) 698 bytes
0 Dir(s) 123,998,978,048 bytes free
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at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
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C:\Program Files\Java\jdk1.6.0_21\bin>
Thoughts please.

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class Foo {
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For some runs, I get 2x speedup as where were no false sharing. But occasionally, I get very bad performance.
The penalty of false sharing can be reduce by binding the two threads to cores that share the same L2 cache.
But this is not an acceptable solution because I want scalability beyond 2 threads and want to remove the
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Traditional solution to avoid false sharing is either to align each object at the cache line boundary, or to pad the object
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Edited by: Grant@FDU on May 5, 2009 9:14 PM
Edited by: Grant@FDU on May 5, 2009 9:15 PM
Edited by: Grant@FDU on May 5, 2009 9:16 PM
Edited by: Grant@FDU on May 5, 2009 9:17 PM
Edited by: Grant@FDU on May 5, 2009 9:17 PM

You cannot guarantee that two objects will be consecutive in memory or that they will stay consecutive (as the object can be moved around to compact memory usage)
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Is it possible to run all OS and programs on Mountain Lion?

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Please accept my apologies if this is posted in the wrong section, I was a little unsure in which community to post this.
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Hi
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Cheers
ThinkPad X220
i7-2620M
Corsair Neutron GTX SSD 480gb
8gb Crucial RAM
IPS 12.5 3x3 display
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9 cell battery
bluetooth
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Phychopomp1,
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Hope this helps,
David
Windows Outreach Team – IT Pro
http://www.microsoft.com/springboard

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