Question

I have an exe file which takes a file name as input.
When I execute it as a command like:

xyz.exe c:\input.txt c:\ouput.txt

It all works as expected.

But how to execute this is java?

This is the one i used and am not getting the ouput in the files:

String[] str = {"c:/input.txt","c:/output.txt"};
Process p = rt.exec("c:/xyz.exe",str); 

Answer 1

You’re using the method:

public Process exec(String command,
                    String[] envp)

where envp is a (quote) “array of strings, each element of which has environment variable settings in the format name=value, or null if the subprocess should inherit the environment of the current process.”

Try this instead:

String[] command = {"c:/xyz.exe", "c:/input.txt", "c:/output.txt"}; 
Process p = Runtime.getRuntime().exec(command);
// ...

Also read this article that explains the pitfalls of Runtime.exec(...): http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html