java execute cmd file fails

Question

I am writing a java program which executes a cmd-file at some point. Both are in the same directory.

I am using the ProcessBuilder, since it is more flexible. However when I run this code it fails:

String current_directory = System.getProperty("user.dir");

 ProcessBuilder builder=new ProcessBuilder(current_directory+"\\"+ "myCmdFile.cmd");
 builder.directory(new File(current_directory));
 File log = new File("log.txt");
 builder.redirectErrorStream(true);
 builder.redirectOutput(Redirect.appendTo(log));
 Process process=builder.start();
 process.waitFor();
 System.out.println("CMD file executed");

I get this exception:

java.io.IOException: Cannot run program "C:\test\myCmdFile.cmd" (in directory "C:\test"): No such file or directory
    at java.lang.ProcessBuilder.start(Unknown Source)
    at org.java.test.executeCmdFile(MyMainClass.java:189)
    at org.java.test.main(MyMainClass.java:70)
Caused by: java.io.IOException: No such file or directory   
    at java.lang.ProcessImpl.openForAtomicAppend(Native Method)
    at java.lang.ProcessImpl.newFileOutputStream(Unknown Source)
    at java.lang.ProcessImpl.start(Unknown Source)
    ... 3 more

However, when I comment out these lines than it works:

  ProcessBuilder builder=new ProcessBuilder(current_directory+"\\"+ 
  "myCmdFile.cmd");
    //builder.directory(new File(current_directory));
    //File log = new File("log.txt");
    // builder.redirectErrorStream(true);
    // builder.redirectOutput(Redirect.appendTo(log));
    Process process=builder.start();
    process.waitFor();
    System.out.println("CMD file executed");

I need these lines, since I want to have log messages.

Answer 1

I found my error...it was a stupid one..This code actually works:

String current_directory = System.getProperty("user.dir");

 ProcessBuilder builder=new ProcessBuilder(current_directory+"\\"+ "myCmdFile.cmd");
 builder.directory(new File(current_directory));
 File log = new File("log.txt");
 builder.redirectErrorStream(true);
 builder.redirectOutput(Redirect.appendTo(log));
 Process process=builder.start();
 process.waitFor();
 System.out.println("CMD file executed");

The problem was this line:

 File log = new File("log.txt");

In my production environment it was a long path (which was wrong), however for demonstration purposes I changed it, before I posted the question here. I thought that the problem was connected with the cmd-file the exception told me that the whole time...now after i gave a correct path for the log-file it works..thx everyone