code: private static TableMapper getTableMapper(Class<?> entityClass) {
          // 表名
          TableMapper tableMapper = new TableMapper();
          String tableName = null;
          if (entityClass.isAnnotationPresent(Table.class)) {
              Table table = entityClass.getAnnotation(Table.class);
              if (!table.name().equals("")) {
                  tableName = table.name();
              } else {
                  tableName = camelhumpToUnderline(entityClass.getSimpleName());
              }
          }
  
          if (tableName == null || tableName.equals("")) {
              throw new RuntimeException("实体" + entityClass.getName() + "不存在'Table'注解");
          }
  
          tableMapper.setName(tableName);
          return tableMapper;
      }
docs: 获取实体Table映射信息