code: private URI findFile(final String filePath, final boolean upload) {
          try {
              URI fileURI;
              try {
                  fileURI = _hadoopDefaultFS.getUri().resolve(filePath);
              } catch (final Exception e) {
                  fileURI = null;
              }
  
              if ((fileURI == null || !_hadoopDefaultFS.exists(new Path(fileURI))) && upload) {
                  final File file = new File(filePath);
                  if (!file.isFile()) {
                      throw new IllegalArgumentException("'" + filePath + " does not exist, or is not a file");
                  }
  
                  final String fileName = file.toPath().getFileName().toString();
                  return _applicationDriver
                          .copyFileToHdfs(file, DATACLEANER_TEMP_DIR + "/" + UUID.randomUUID() + fileName);
              }
  
              return fileURI;
          } catch (final IOException e) {
              throw new IllegalArgumentException("Path '" + filePath + "' is not a proper file path");
          }
      }
docs: Tries to find a file on HDFS, and optionally uploads it if not found.
  
  @param filePath Path of the file to find
  @param upload true if file upload should be attempted.
  @return Either the resolved URI, or the uploaded file.