留着 自用研究

@SuppressWarnings("unchecked") public static List<Map<String, Object>> getJsonTree(List<?> source) { Map<String, Map<String, Object>> sourceMap = convert2Map(source); List<Map<String, Object>> resultList = new ArrayList<>(); Set<String> keySet = sourceMap.keySet(); for (String key : keySet) { String parentKey = sourceMap.get(key).get("parentId").toString(); Map<String, Object> parent = sourceMap.get(parentKey); if (parent != null) { List<Object> childs = (List<Object>) parent.get("children"); childs.add(sourceMap.get(key)); parent.put("child", childs); } } for(String key : keySet){ String parentKey = sourceMap.get(key).get("parentId").toString(); Map<String, Object> parent = sourceMap.get(parentKey); if (parent == null) { resultList.add(sourceMap.get(key)); } } return resultList; } private static Map<String, Map<String, Object>> convert2Map(List<?> source) { Map<String, Map<String, Object>> resultMap = new HashMap<>(); for (Object s : source) { Map<String, Object> childMap = JacksonUtil.read2Map(s.toString()); childMap.put("children", new ArrayList<Object>()); resultMap.put(childMap.get("id").toString(), childMap); } return resultMap; }