Deleting temporary file using Java runtime.exec function

Question

I'm stuck in a situation.

String tmpfolder = System.getProperty("java.io.tmpdir");
\\this is the path C:\Users\biraj\AppData\Local\Temp\ 
tmpfolder = tmpfolder.replace("\\", "\\\\"); 
Runtime.getRuntime().exec("cmd /c del "+tmpfolder+"IEDriver.dll /f /s /q"); 

When I run this code it does not delete the IEDriver.dll file. But when I give the static path of the temporary folder then it deletes that file:

Runtime.getRuntime().exec("cmd /c del C:\\Users\\biraj\\AppData\\Local\\Temp\\IEDriver.dll /f /s /q"); 

Can anyone explain to me why the first code didn't work? What's wrong in that?

Answer 1

The problem is that you are changing literal \\ into a literal \\\\ in your second line. When we write code, we use \\\\ inside a string to represent a literal \\ to the program, but your tmpfolder variable already has the correct literal \\ inside it.

If you delete the following line, it should work.

tmpfolder = tmpfolder.replace("\\", "\\\\"); 

The easiest way to understand the difference is to just print the string you constructed, as well as the literal string and compare them visually.

System.out.println("cmd /c del "+tmpfolder+"IEDriver.dll /f /s /q");
System.out.println("cmd /c del C:\\Users\\biraj\\AppData\\Local\\Temp\\IEDriver.dll /f /s /q")

Another possible problem is that you need to change

"IEDriver.dll /f /s /q" 

to

 "\\IEDriver.dll /f /s /q"

Of course the visual comparison will answer this question definitively.