多级菜单无限递归

最新推荐文章于 2024-04-26 09:09:20 发布

转载最新推荐文章于 2024-04-26 09:09:20 发布 · 131 阅读

CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/laixin09/p/10006038.html

本文深入探讨了一种用于处理层级数据结构的递归聚合算法，该算法能够有效地将具有层级关系的数据进行聚合处理，形成清晰的主从结构，便于后续的数据分析和展示。通过实例演示了如何使用递归算法来加载子级文章类型，并将其整合到父级类型中，形成树状数据结构。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

public Map<String, Object> findAll(HttpServletRequest request) {
Map<String, Object> rs = new HashMap<String, Object>();

List<Map<String, Object>> articleTypeList = articleTypeDao.findAllMap();
List<Map<String, Object>> loadChildArticleType = this.loadChildArticleType(articleTypeList, 1);

return rs;
}

/**
* 递归聚合
*/
private List<Map<String, Object>> loadChildArticleType(List<Map<String, Object>> allList, int level) {
if (allList == null || allList.isEmpty() || level == 0) {
return allList;
}
List<Map<String, Object>> mainList = new ArrayList<>();
List<Map<String, Object>> childList = new ArrayList<>();
for (Map<String, Object> item : allList) {
if (toInteger(item.get("level")) == level) {
mainList.add(item);
} else if (toInteger(item.get("level")) == level + 1) {
childList.add(item);
}
}
allList.removeAll(mainList);
if (!childList.isEmpty()) {
childList = this.loadChildArticleType(allList, toInteger(childList.get(0).get("level")));
}
for (Map<String, Object> main : mainList) {
for (Map<String, Object> child : childList) {
if (child.get("upperId").equals(main.get("id"))) {
List<Map<String, Object>> typeList;
if (main.get("childTypeList") == null) {
typeList = new ArrayList<>();
} else {
typeList = (List<Map<String, Object>>) main.get("childTypeList");
}
typeList.add(child);
main.put("childTypeList", typeList);
}
}
}
return mainList;
}

实体字段

private Long id; 主键
private Long upperId; 上级id
private int level; 第几极

转载于:https://www.cnblogs.com/laixin09/p/10006038.html