#vulnerable code 
                              private ClassLoader getDriverClassLoader() {
    File localDriverPath = getCustomDriverPath();
    if (driverClassLoader != null) {
      return driverClassLoader;
    } else if (localDriverPath.exists()) {
      try {
        List<URL> urlList = new ArrayList<URL>();
        for (File file : localDriverPath.listFiles()) {
          String filename = file.getCanonicalPath();
          if (!filename.startsWith("/")) {
            filename = "/" + filename;
          }
          urlList.add(new URL("jar:file:" + filename + "!/"));
          urlList.add(new URL("file:" + filename));
        }
        URL[] urls = urlList.toArray(new URL[urlList.size()]);
        return new URLClassLoader(urls);
      } catch (Exception e) {
        throw new MigrationException("Error creating a driver ClassLoader. Cause: " + e, e);
      }
    }
    return null;
  } 
                            #location 8 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                              private ClassLoader getDriverClassLoader() {
    File localDriverPath = getCustomDriverPath();
    if (driverClassLoader != null) {
      return driverClassLoader;
    } else if (localDriverPath.exists()) {
      try {
        List<URL> urlList = new ArrayList<>();
        File[] files = localDriverPath.listFiles();
        if (files != null) {
          for (File file : files) {
            String filename = file.getCanonicalPath();
            if (!filename.startsWith("/")) {
              filename = "/" + filename;
            }
            urlList.add(new URL("jar:file:" + filename + "!/"));
            urlList.add(new URL("file:" + filename));
          }
        }
        URL[] urls = urlList.toArray(new URL[0]);
        return new URLClassLoader(urls);
      } catch (Exception e) {
        throw new MigrationException("Error creating a driver ClassLoader. Cause: " + e, e);
      }
    }
    return null;
  }