code: public FileScanner setSearchTypes(String... srTypes) {
          if (srTypes == null || srTypes.length == 0) {
              this.srTypes = new String[0];
          } else {
              this.srTypes = srTypes;
          }
          return this;
      }
docs: 如果传入null 或者 空字符 数组, 表示各种文件全支持
  
  @param srTypes