code: public Configuration load(String pu)
      {
          Configuration conf = new Configuration().addProperties(puMetadata.getProperties());
          String propertyFileName = externalProperties != null ? (String) externalProperties
                  .get(PersistenceProperties.KUNDERA_CLIENT_PROPERTY) : null;
          if (propertyFileName == null)
          {
              propertyFileName = puMetadata != null ? puMetadata
                      .getProperty(PersistenceProperties.KUNDERA_CLIENT_PROPERTY) : null;
          }
          if (propertyFileName != null)
          {
              PropertyType fileType = PropertyType.value(propertyFileName);
  
              switch (fileType)
              {
              case xml:
                  conf.configure(propertyFileName);
                  break;
  
              case properties:
                  Properties props = new Properties();
  
                  InputStream ioStream = puMetadata.getClassLoader().getResourceAsStream(propertyFileName);
                  if (ioStream == null)
                  {
                      propertyFileName = KunderaCoreUtils.resolvePath(propertyFileName);
                      try
                      {
                          ioStream = new FileInputStream(new File(propertyFileName));
                      }
                      catch (FileNotFoundException e)
                      {
                          log.warn("File {} not found, Caused by ", propertyFileName);
                      }
                  }
                  try
                  {
                      if (ioStream != null)
                      {
                          props.load(ioStream);
                      }
                  }
                  catch (IOException e)
                  {
                      log.error("Skipping as error occurred while loading property file {}, Cause by : {}.",
                              propertyFileName, e);
                  }
  
                  conf.addProperties(props);
                  break;
  
              default:
                  log.error("Unsupported type{} for file{}, skipping load of properties.", fileType, propertyFileName);
                  break;
              }
          }
  
          return conf;
      }
docs: Reads property file which is given in persistence unit
  
  @param pu