PageInfo 里的EMPTY属性和emptyPageInfo() 方法返回的对象不正确

[xiao8Git]

测试代码

PageInfo<MemberCard> objectPageInfo = PageMethod.startPage(1, 10)
    .doSelectPageInfo(() -> baseMapper.getXxxx()
);

List<MemberCard> list = objectPageInfo.getList();
if (CollectionUtils.isEmpty(list)) {
    PageInfo empty = PageInfo.EMPTY;
    log.warn("hashCode:{}",empty.hashCode());
    List<MemberCard> pageList = empty.getList();
    pageList.add(new MemberCard());
    empty.setList(pageList);
    empty.setTotal(pageList.size());
    log.warn("Total:{}",empty.getTotal());
    return empty;
}

原 SQL

SELECT count(0) FROM member_card where 1=2

期望的结果：

PageInfo.EMPTY 永远返回空对象

日志内容

17:47:06.804 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Preparing: SELECT count(0) FROM member_card where 1=2
17:47:06.805 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Parameters:
17:47:06.811 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - <== Total: 1
17:47:06.812 WARN c.w.l.u.s.xxxxx - hashCode:1045255393
17:47:06.812 WARN c.w.l.u.s.xxxxx - Total:3
17:47:16.582 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Preparing: SELECT count(0) FROM member_card where 1=2
17:47:16.583 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Parameters:
17:47:16.589 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - <== Total: 1
17:47:16.590 WARN c.w.l.u.s.xxxxx - hashCode:1045255393
17:47:16.590 WARN c.w.l.u.s.xxxxx - Total:4
17:47:16.820 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Preparing: SELECT count(0) FROM member_card where 1=2
17:47:16.821 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Parameters:
17:47:16.827 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - <== Total: 1
17:47:16.827 WARN c.w.l.u.s.xxxxx - hashCode:1045255393
17:47:16.828 WARN c.w.l.u.s.xxxxx - Total:5
17:47:17.015 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Preparing: SELECT count(0) FROM member_card where 1=2
17:47:17.016 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Parameters:
17:47:17.022 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - <== Total: 1
17:47:17.024 WARN c.w.l.u.s.xxxxx - hashCode:1045255393
17:47:17.024 WARN c.w.l.u.s.xxxxx - Total:6
17:47:17.282 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Preparing: SELECT count(0) FROM member_card where 1=2
17:47:17.283 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - ==> Parameters:
17:47:17.290 DEBUG c.w.l.u.s.m.M.xxxXx_COUNT - <== Total: 1
17:47:17.292 WARN c.w.l.u.s.xxxxx - hashCode:1045255393
17:47:17.292 WARN c.w.l.u.s.xxxxx - Total:7

原因

PageInfo 类的EMPTY 属性是static final 只能赋值一次，全局只有一个，但暴露的方法可以被内部和外部修改，

public static final PageInfo EMPTY = new PageInfo(Collections.emptyList(), 0);

[abel533]

来个PR？