Java - how to find out if a directory is being used by another process?

TASKKILL /PID %PID%

import java.io.IOException;
import java.nio.file.FileSystems;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.PathMatcher;
import java.nio.file.Paths;
import java.nio.file.SimpleFileVisitor;
import java.nio.file.attribute.BasicFileAttributes;

public class MyVisitor extends SimpleFileVisitor<Path> {

    PathMatcher matcher = FileSystems.getDefault().getPathMatcher("glob:data");

    @Override
    public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) throws IOException {
        if (matcher.matches(dir.getFileName())) {
            System.out.println("dir found " + dir);
        }
        return FileVisitResult.CONTINUE;
    }

    @Override
    public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
        if (matcher.matches(file.getFileName())) {
            System.out.println("file found " + file);
        }

        return FileVisitResult.CONTINUE;
    }

    public static void main(String[] args) throws IOException {
        Files.walkFileTree(Paths.get("full/path/to/your/search"), new MyVisitor());
    }
}

try{
               Runtime rt = Runtime.getRuntime();
               Process proc = rt.exec("cmd /c netstat -ano | findstr 9090");

               BufferedReader stdInput = new BufferedReader(new
               InputStreamReader(proc.getInputStream()));
               String s = null;
               if ((s = stdInput.readLine()) != null) {
               int index=s.lastIndexOf(" ");
               String sc=s.substring(index, s.length());

               rt.exec("cmd /c Taskkill /PID" +sc+" /T /F");

       }
               JOptionPane.showMessageDialog(null, "Server Stopped");
         }catch(Exception e){
               JOptionPane.showMessageDialog(null, "Something Went wrong with server");
           }