Can I execute a cmd command through java?

Question

I am making a program that needs some of the Java libraries installed already into the computer and also the "classpath" environment variable to be set.

I want to run the set classpath command. Can I do it through java? Or do I need to do something else? Any Example?

You can use `Runtime.getRuntime().exec("")` to execute commandline commands. But i'm not sure if this is really what you want to do.. — micha, Dec 18 '12 at 10:49
try java -classpath .;myjar.jar;lib/referenced-class.jar my.package.MainClass — Mohammod Hossain, Dec 18 '12 at 10:50

score 2 · Answer 1 · answered Dec 18 '12 at 10:49

2

All you need is ProcessBuilder

answered Dec 18 '12 at 10:49

NiranjanBhat

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score 2 · Accepted Answer · answered Dec 18 '12 at 10:49

2

If you want to set a system property, you can use System.setProperty(key,value).

answered Dec 18 '12 at 10:49

Matthijs Bierman

1,720
9
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I think that was what I needed-So I know now that Environment variables can be changed without running cmd command in Java.Thanks – Soul Enrapturer Dec 19 '12 at 05:08
Just know that these properties are *not* global. See this answer: http://stackoverflow.com/a/908965/226449 – Matthijs Bierman Dec 19 '12 at 08:55
Do you mean the environment variable that i have changed won't have a changed value in another program that I later or in parallel run on that machine?What about if I have multiple threads in a process?Will it be working there too? – Soul Enrapturer Dec 20 '12 at 06:27
Another JVM/process will not have the changed value, correct. Within the same process (i.e. another thread) it will show the changed value. – Matthijs Bierman Dec 21 '12 at 15:57

score 2 · Answer 3 · answered Dec 18 '12 at 10:50

2

Yes, you can. Here's are some examples to show you how to do it:

http://www.javaworld.com/jw-12-2000/jw-1229-traps.html

http://www.ehow.com/way_5660016_java-runtime-exec-tutorial.html

answered Dec 18 '12 at 10:50

duffymo

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score 2 · Answer 4 · answered Dec 18 '12 at 10:59

Something like

public static void main(String[] args)
{
    try
    {
        if (args == null || (args != null && args.length != 1)) 
        {
        System.out.println("Please provide a command");
        }
        Runtime.getRuntime().exec(args);
    } 
    catch (Exception ex) 
    {
        ex.printStackTrace();
    }
}

score 1 · Answer 5 · answered Dec 18 '12 at 10:49

1

set.exe is a program like any other. You can start it with Runtime.exec().

answered Dec 18 '12 at 10:49

Philipp

67,764
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Can I execute a cmd command through java?

5 Answers5