code: private List<String> readDupAccounts(InputStream dupAccountsStream)
          throws IOException {
          ObjectMapper objMapper = new ObjectMapper();
          return objMapper.readValue(
              dupAccountsStream,
              new TypeReference<List<String>>() {
              });
      }
docs: Reads duplication account listing. File is expected to be a JSON
  formatted list of String values.
  
  @param dupAccountsStream stream
  @return list of duplication accounts
  @throws IOException