@Nullable
  private static String tryCopy(@NotNull String agentDir,
                                @NotNull String agentName,
                                @NotNull File targetDir,
                                @Nullable FileFilter fileFilter) {
    if (targetDir.getAbsolutePath().contains(" ")) return null;
    try {
      if (fileFilter == null) {
        FileUtil.copy(new File(agentDir, agentName), new File(targetDir, agentName));
      }
      else {
        FileUtil.copyDir(new File(agentDir), targetDir, fileFilter);
      }
      LOG.info("Agent jars were copied to " + targetDir.getPath());
      return targetDir.getPath();
    }
    catch (IOException e) {
      LOG.info(e);
      return null;
    }
  }
@Nullable
  private static String tryCopy(@NotNull String agentDir,
                                @NotNull String agentName,
                                @NotNull File targetDir,
                                @Nullable FileFilter fileFilter)