Using Java to do a WIndows command line command

Question

I am running the Java code from Directory A, and there is a myBat.bat file there too. I want to use Java to execute the bat file. The contents of the myBat.bat is : svn update C:\DirectoryB\file.txt
I have already downloaded the Slik SVN Windows command line client. When i double click on the bat file, it svn updates the file correctly. But not when i run my Java code.

Process p = Runtime.getRuntime().exec("cmd /C C:\\DirectoryA\\myBat.bat");

The test fails because it cannot find the file.txt that it was expecting. In order to really test the svn update, i have deleted the svn file in DirectoryB. Double clicking the bat file repopulates file.txt. The test fails with:
The system cannot find the file specified) at java.io.FileInputStream.open

• JustinKSU: Does it work if you use the full path to the batch file?
• stumped: I just added the full path and it doesn't work either.
• MByD: There's too much that we miss. please explain what doesn't work and how it doesn't work.
• Kal: What does happen when you run it from your java code? Are you able to run any process successfully? Try replacing the contents with something other than "svn update"
• stumped: I replace the bat file contents with : copy C:\a.txt C:\DirectoryB and this did not work either when i executed the Java code. Again, if i double click the batch file directly, it works.

Answer 1

Try it this way, should work if your bat file is correct:

try {
 Process p = Runtime.getRuntime().exec("cmd /c start c:\\DirectoryA\\myBat.bat");
} catch (IOException ex) {
 ...
}

The idea is that .bat files are not considered to be direct executables by the Runtime.