static public String validateTblColumns(List<FieldSchema> cols) {
    for (FieldSchema fieldSchema : cols) {
      // skip this, as validateColumnName always returns true
      /*
      if (!validateColumnName(fieldSchema.getName())) {
        return "name: " + fieldSchema.getName();
      }
      */
      String typeError = validateColumnType(fieldSchema.getType());
      if (typeError != null) {
        return typeError;
      }
    }
    return null;
  }
Finds a free port on the machine, but allow the
ability to specify a port number to not use, no matter what.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/utils/MetaStoreServerUtils.java