### Question:
SysRoleServiceImpl implements SysRoleService { @Override public List<SysRole> SelectAll() { return sysRoleMapper.selectAll(); }  @Override List<SysRole> SelectAll();  }### Answer:
@Test public void test1(){ List<SysRole> sysRoleList=sysRoleService.SelectAll(); log.info("[普通写法] - [{}]", sysRoleList); PageInfo<Object> pageInfo= PageHelper.startPage(1,1).doSelectPageInfo(() -> sysRoleService.SelectAll()); log.info("[分页]-[{}]",pageInfo); }