树形结构菜单

项目中查询菜单目录表，里面有父子关系，根据父子关系，把菜单目录表展示成树的形式

　　查询出所有的菜单目录内容

SysUserMVO sessionUser = SecurityManager.getSessionUser();
List<MenuCatalogMVO> catalogs = sessionUser.getMenuCatalog();

　　将数据根据父子关系展示成json格式

Map<String,Object> leafMap = getLevelMenuCatalog(catalogs,leafNodeIds,MENU_LV);

public Map<String, Object> getLevelMenuCatalog(List<MenuCatalogMVO> catalogs, List<String> parentCatalogIds, String... catalogCodes) {
    List<Object> treeList = new LinkedList<Object>();
    List<String> leafNodeId = new LinkedList<String>();
    Map<String, Object> rsMap = new HashMap<String, Object>();
    for (MenuCatalogMVO menuCatalog : catalogs) {
        if ((parentCatalogIds != null && parentCatalogIds.size() > 0) ? parentCatalogIds.contains(menuCatalog.getParentCatalogId()) : StringUtils.isBlank(menuCatalog.getParentCatalogId())) {
            if (catalogCodes.length > 0 && Arrays.asList(catalogCodes).contains(menuCatalog.getCatalogCode())) {
                Map<String, Object> treeMap = new HashMap<String, Object>();
                treeMap.put("id", menuCatalog.getMenuCatalogId());
                treeMap.put("text", menuCatalog.getCatalogName());
                treeMap.put("code", menuCatalog.getCatalogCode());
                treeMap.put("parentId", menuCatalog.getParentCatalogId());
                childMenuCatalog(treeMap, catalogs, catalogCodes, leafNodeId);
                treeList.add(treeMap);
            }
        }
    }
    rsMap.put("LEAFNODEIDS", leafNodeId);
    JSONArray jo = JSONArray.fromObject(treeList);
    String rs = jo.toString();
    rsMap.put("RS", rs);
    return rsMap;
}

public void childMenuCatalog(Map<String, Object> parentMap, List<MenuCatalogMVO> catalogs, String[] catalogCodes, List<String> leafNodeId) {
    List<Object> treeList = new LinkedList<Object>();
    for (MenuCatalogMVO menuCatalog : catalogs) {
        Map<String, Object> treeMap = new HashMap<String, Object>();
        if (catalogCodes.length > 0 && Arrays.asList(catalogCodes).contains(menuCatalog.getCatalogCode())) {
            if (parentMap.get("id").equals(menuCatalog.getParentCatalogId())) {
                treeMap.put("id", menuCatalog.getMenuCatalogId());
                treeMap.put("text", menuCatalog.getCatalogName());
                treeMap.put("code", menuCatalog.getCatalogCode());
                treeMap.put("parentId", menuCatalog.getParentCatalogId());
                childMenuCatalog(treeMap, catalogs, catalogCodes, leafNodeId);
                treeList.add(treeMap);
            }
        }
    }
    if (treeList.size() > 0) {
        parentMap.put("children", treeList);
    } else {
        leafNodeId.add((String) parentMap.get("id"));
    }
}

　catalog = (String) leafMap.get("RS");

　　这样打印出的catalog就是有层级关系的了