code: @Nonnull
      public static String getFileName(@Nonnull String filePath) {
          int idx = filePath.lastIndexOf('\\');
          if(idx>=0)
              return getFileName(filePath.substring(idx+1));
          idx = filePath.lastIndexOf('/');
          if(idx>=0)
              return getFileName(filePath.substring(idx+1));
          return filePath;
      }
docs: Cuts all the leading path portion and get just the file name.