Strange behavior when using Runtime.exec() to run batch file

I've been struggling with this for hours.
I have a Swing application which upon clicking a button, I want to execute a batch file. This batch file itself uses a command window.
When I use
Runtime load = Runtime.getRuntime();
load.exec("cmd /c start c:\\renew\\renew2\\bin\\win\\renew.bat");
The program (Renew) will start up no problem, but when I exit Renew, the command window stays put. I want the command window to close. Running Renew stand-alone, upon closing Renew, it will exit the command window.
When I use
Runtime load = Runtime.getRuntime();
load.exec("cmd /c c:\\renew\\renew2\\bin\\win\\renew.bat");
or
Runtime load = Runtime.getRuntime();
load.exec("c:\\renew\\renew2\\bin\\win\\renew.bat");
When I press the button, sometimes the Renew application will come up right away, sometimes the Renew application will come up after a very long delay, and most times, the Renew application will only come up after I have closed the Swing frame where the button is located. When I use this code, the command window that Renew uses is never visible.
What I want is to simply have the Renew application behave the same exact way launching from my Swing application as when Renew is being run standalone.
Any suggestions? Thanks so much.
Sincerely,
Will

Getting rid of start makes the startup time very variable. Sometimes it starts up right away, sometimes after many minutes, most times only after I close my application.
Thanks, Any other suggestions?
(BTW, I have read the famous "When Runtime.exec() won't" article, and have tried its suggestions to no avail)
Message was edited by:
willies777

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Using runtime.exec to zip some files

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Yet, when I copy the string from the log, and paste it in a terminal, it properly creates the zip files. So, I know I have the correct command string, it just does not seem to be working within the java application. Also, the command string uses fully qualified directories, so it is not a directory issue.
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adamSpline wrote:
Hi,
I am using runtime.exec to try to automatically zip a bunch of files on a server. However, it does not seem to be working.
Before I execute the command, I save the zip command in a string. I then print the string to a log file, and then execute the runtime zip command. But nothing happens. Within Runtime.exec() any command does not run in a shell and I bet you use wild cards and/or other commands to be interpreted by a shell which will not be interpreted since there is no shell. And, since you don't mention error messages or the return code, I will also bet you don't process the Process stdout , stderr and the return code properly.
It looks to me like you have fallen for at least two for the traps in [http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html|http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html].
>
Yet, when I copy the string from the log, and paste it in a terminal, it properly creates the zip files. So, I know I have the correct command string, it just does not seem to be working within the java application. Also, the command string uses fully qualified directories, so it is not a directory issue.
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Help please! [using Runtime.exec() to run find command in UNIX]

Hi guys! im trying to use exec() to run the UNIX find command
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Could someone please help me on this one. Many thanks! =)
import java.io.*;
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I don't see anythi obvious. In both catch blocks, call printSckTrace on the exception yhou caught.
I think the real culprit is the ~ though.
~ is interpreted by some (most?) shells to men home dir. However, when you just exec a command, you don't have a shell to do that interpretation for you, so it's looking for a directory that's literally named ~.
Either exec a shell (read the man pages for the shell of your choice, but for zsh I think it's "/bin/zsh -c find ~ blah blah blah) or else just put the actual path to your home directory into the string you pass to exec. You can get that from System.getProperty("user.home").

BufferedReader blocks when using Runtime.exec()

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I use this type of thing in my code using JDK1.3.1. Only difference is I don't use set up the readers in threads. I suspect you have a thread deadlock, but I can't see why. Do you have to have the i/o stream readers in the thread?

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I have hit a wall in trying to figure this one out. The problem I am having is that my program does not start the oscilloscope when it should.
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Solved!
Go to Solution.
Attachments:
tktds8k.pdf ‏1424 KB
set_up_osc.vi ‏32 KB

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[email protected]

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Oscar

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Thankyou VeryMuch
Yours
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import java.io.InputStream;
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}The inputStream of the process doesnt get printed at all , the loop condition in StreamGobbler 'while ( (line = br.readLine()) != null)
' is never true.
Also , in random cases i've seen the System.out.println("exitVAl "+exit); line executing before the System.out.println("Start Reading"); line , and i though proc.waitFor() would guarentee otherwise.

thx guys for ur replies . The issue was because of some browser security system ( or so they said . ).However i'm still puzzled about the 'waiting for the stream to finish' part .
paul.miner wrote:
{I think the process is allowed to end with output still in the >>buffers, ..so this would be expected. You should be waiting for >>your .streams to finish, since that's what you really >>care .about. .Also, .you need to add synchronization between your >>threads so you can accurately retrieve "MAC". Also, do not break out >>of the loop when you find what you're looking for, you should >>continue .reading until the end of the stream.Wasn't I suppose to be reading out of the stream to prevent an overflow?Also the break is done there are multiple lines like 'Physical address .....: xxxxxxxxxx ' in the output , and the macid is the first one.About the ProcessBuilder , I'll look into it . Thx for your advice.

Strange behavior when using Runtime.exec() to run batch file

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