/**
   * DOC bZhou Comment method "create".
   *
   * @param fileExtension
   * @return
   */
  public AElementPersistance create(String fileExtension) {

    if (FactoriesUtil.ANA.equals(fileExtension)) {
      return createAnalysisWrite();
    } else if (FactoriesUtil.REP.equals(fileExtension)) {
      return createReportWriter();
    } else if (FactoriesUtil.PROV.equals(fileExtension)) {
      return createDataProviderWriter();
    } else if (FactoriesUtil.PATTERN.equals(fileExtension)) {
      return createPatternWriter();
    } else if (FactoriesUtil.DQRULE.equals(fileExtension)) {
      return createdRuleWriter();
    } else if (FactoriesUtil.SOFTWARE_SYSTEM.equals(fileExtension)) {
      return createSoftwareSystemWriter();
    } else if (FactoriesUtil.DEFINITION.equals(fileExtension)) {
      return createIndicatorDefinitionWriter();
    }

    return null;
  }