Executing Java Object in C# - C# Discussion Boards

Re: Best way to get an image of a Form

12-May-09 0:56

Hi,

I would like to be able to capture an image of an arbitrary window (though it is most likey that it will be a window I create). What is the best way to do this? I am currently using the Graphics.CopyFromScreen method to paint the section of the screen the window occupies to a bitmap but this has the obvious disadvantage that if the window is behind another, the image will also capture this overlap. Is there any other way of doing this that would solve this problem?

Thanks,

Steve

Christian Graus12-May-09 1:17

Christian Graus

12-May-09 1:17

I believe the control themselves have a rendertobitmap method that you can call, which I assume triggers a paint event but renders to a bitmap, not the screen.

Re: Best way to get an image of a Form

Steve_12-May-09 1:46

Re: Best way to get an image of a Form

12-May-09 1:46

I had a look for one initially but didn't find anything. Having had another look I can see Control.DrawToBitmap, perhaps I should have looked harder the first time!

Thanks for your advice.

Steve

Christian Graus12-May-09 1:47

Christian Graus

12-May-09 1:47

*grin* glad to help

Executing Java Object in C#

Mninawa12-May-09 0:54

Mninawa

12-May-09 0:54

I have this task, i need to call a Java Application using a web-service call.I need to know if someone has a clue on how to do that,so far this is my attempt.

string cmd ="C:\Program Files\Java\jre1.6.0\bin\Java.exe"; 
//We use this command to invoke or start the java application which take argument infront.

string cmdParams="java -Xms32m -Xmx1g -Djava.library.path=d:\cep\col\sql -classpath d:\cep\col\commons-net-1.4.1.jar;d:\cep\col\commons-codec-1.3.jar;d:\cep\col\sql\sqljdbc.jar;d:\cep\col\DialogInput.jar za.co.lightWave.control.DialogInputControl";


using (Process process = Process.Start(new ProcessStartInfo(cmd, cmdParams)))
            {
    
                process.StartInfo.RedirectStandardOutput = true;
                process.StartInfo.RedirectStandardError= true;

                process.StartInfo.UseShellExecute = false;
                process.StartInfo.RedirectStandardOutput = true;
                process.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
    
                process.Start();

                process.WaitForExit(timeout);
                return process.ExitCode;
            }

I need to know what is an effective way of executing that command,what i have currently is

java.lang.NoClassDefFoundError: java Exception in thread "main"

Thank you in advance
Mninawa

Steve_12-May-09 0:59

12-May-09 0:59

Hi,

Have you tried running the command you are attempting to run in the command line first to make sure that the command actually works? What you are getting is an error from Java that says it cannot find a certain class. This is almost always a problem with the classpath argument of the command. Try debugging the command in cmd.exe first and then once you are sure the command works, try doing it in code.

Steve

Steve_12-May-09 1:03

12-May-09 1:03

PS.

I just had a closer look at your commands. You are setting the command to call the Java virtual machine (Java.exe) which is fine. But you are then setting the first argument (in your cmdParams) to "java" then "-xms32m...etc". Did you mean to put jar instead of java? When you execute a JAR file on the command line it should be something like "C:\whatever\Java.exe -jar MyJar.jar". Take a look at the documentation for the Java Virtual Machine when running JAR files.

Steve

Mninawa12-May-09 1:59

Mninawa

12-May-09 1:59

Hi Steve,thanx for your help.

On that not you are quite right,In the documentations for JVM,this is how you would execute .jar file,but now what i have is the combination of libraries,which makes up an application caller,which is that cmdParam,
well i have to find a way to execute them in C# and I thought using this way would solve the problem.

I thought one might have a solution besides the one in did,because i have to do them that way.
Mninawa

Luc Pattyn12-May-09 2:05

Luc Pattyn

12-May-09 2:05

Hi,

1.
to execute a java class, you should issue the command "java [options] classname"
which means "java" is the command, and everything else is in the arguments.

So I would remove the "java " from cmdParams (I guess you already did that).

2.
Furthermore, in Java there is a direct link between composite class names (as in your "za.co.lightWave.control.DialogInputControl") and your file hierarchy. So your classpath (either the enviroment variable or the options you specify) must lead to the location that is holding
za\co\lightWave\control\DialogInputControl.class

java.lang.NoClassDefFoundError is the error you would get when not satisfying this requirement.

Smile | :)

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memory usage

michaelgr112-May-09 0:11

michaelgr1

12-May-09 0:11

Hello,
I wrote window application that has some datagrids and data from SQL. I saw in task manager that this application uses 23 MB memory. Is it considered as normal / high ? And if high how can i reduce it?
BTW it's only the beginning of the application writing. I will have to add much more datagrids and other stuff...

Rob Philpott12-May-09 0:13

Rob Philpott

12-May-09 0:13

23MB is nothing to concern yourself with at all. It sounds quite modest to me, even for a small application.

Regards,
Rob Philpott.

Simon P Stevens12-May-09 0:27

Simon P Stevens

12-May-09 0:27

.net memory management is different to non.net apps

See previous post and replies here[^] and here[^].

Simon

michaelgr112-May-09 0:31

michaelgr1

12-May-09 0:31

OK thanks.
But i am going to add much more datagrids to this application?
Does using with methods and classes reduces the memory usage or not?
I am nor worried now, but still there will be much more datagrids and stuff (about 10 times more datagrids)