1、通过转化成json封装数据
原始数据如下
[
{
"name":"甘肃省", "pid":0, "id":1 }, { "name":"天水市", "pid":1, "id":2 }, { "name":"秦州区", "pid":2, "id":3 }, { "name":"北京市", "pid":0, "id":4 }, { "name":"昌平区", "pid":4, "id":5 } ] 现需要是使用java将以上数据转为树形结构，转化后下的结构如下
[
{
"children":[ { "children":[ { "name":"秦州区", "pid":2, "id":3 } ], "name":"天水市", "pid":1, "id":2 } ], "name":"甘肃省", "pid":0, "id":1 }, { "children":[ { "name":"昌平区", "pid":4, "id":5 } ], "name":"北京市", "pid":0, "id":4 } ] 代码如下
/** - listToTree - <p>方法说明<p> - 将JSONArray数组转为树状结构 - @param arr 需要转化的数据 - @param id 数据唯一的标识键值 - @param pid 父id唯一标识键值 - @param child 子节点键值 - @return JSONArray */ public static JSONArray listToTree(JSONArray arr,String id,String pid,String child){ JSONArray r = new JSONArray(); JSONObject hash = new JSONObject(); //将数组转为Object的形式，key为数组中的id for(int i=0;i<arr.size();i++){ JSONObject json = (JSONObject) arr.get(i); hash.put(json.getString(id), json); } //遍历结果集 for(int j=0;j<arr.size();j++){ //单条记录 JSONObject aVal = (JSONObject) arr.get(j); //在hash中取出key为单条记录中pid的值 JSONObject hashVP = (JSONObject) hash.get(aVal.get(pid).toString()); //如果记录的pid存在，则说明它有父节点，将她添加到孩子节点的集合中 if(hashVP!=null){ //检查是否有child属性 if(hashVP.get(child)!=null){ JSONArray ch = (JSONArray) hashVP.get(child); ch.add(aVal); hashVP.put(child, ch); }else{ JSONArray ch = new JSONArray(); ch.add(aVal); hashVP.put(child, ch); } }else{ r.add(aVal); } } return r; } 测试代码如下 public static void main(String[] args){ List<Map<String,Object>> data = new ArrayList<>(); Map<String,Object> map = new HashMap<>(); map.put("id",1); map.put("pid",0); map.put("name","甘肃省"); data.add(map); Map<String,Object> map2 = new HashMap<>(); map2.put("id",2); map2.put("pid",1); map2.put("name","天水市"); data.add(map2); Map<String,Object> map3 = new HashMap<>(); map3.put("id",3); map3.put("pid",2); map3.put("name","秦州区"); data.add(map3); Map<String,Object> map4 = new HashMap<>(); map4.put("id",4); map4.put("pid",0); map4.put("name","北京市"); data.add(map4); Map<String,Object> map5 = new HashMap<>(); map5.put("id",5); map5.put("pid",4); map5.put("name","昌平区"); data.add(map5); System.out.println(JSON.toJSONString(data)); JSONArray result = listToTree(JSONArray.parseArray(JSON.toJSONString(data)),"id","pid","children"); System.out.println(JSON.toJSONString(result)); } 2、通过java8 stream转换
我在网上找了很多方法，自己写的这个思路清晰，代码量少，希望能找到志同道合的朋友，看看还有没有优化的地方。
import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; @Data @AllArgsConstructor @NoArgsConstructor public class ZhField { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private String id; /** * 上级领域id */ @Column(name = "parent_id") private String parentId; /** * 领域名称 */ private String name; /** * 排序 */ private Integer sort; } import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; import java.io.Serializable; import java.util.List; import java.util.Map; @Data @AllArgsConstructor @NoArgsConstructor public class TreeMenuNode implements Serializable { private String id; private String parentId; private String name; private Integer sort; private List<TreeMenuNode> children; private Boolean isAble; /**20180929zhw添加 树的额外属性(至少含有父节点ID:"parentId")**/ private Map<String,Object> attributes; } package com.egaoqi.service.impl.company; import com.egaoqi.entity.ZhField; import com.egaoqi.util.TreeMenuNode; import java.util.ArrayList; import java.util.Comparator; import java.util.List; import java.util.Map; import java.util.stream.Collectors; /** * @author zhizhao * @description * @create 2018-11-14 9:07 */ public class toModel { private static void forEach(Map<String, List<TreeMenuNode>> collect, TreeMenuNode treeMenuNode) { List<TreeMenuNode> treeMenuNodes = collect.get(treeMenuNode.getId()); if(collect.get(treeMenuNode.getId())!=null){ //排序 treeMenuNodes.sort((u1, u2) -> u1.getSort().compareTo(u2.getSort())); treeMenuNodes.stream().sorted(Comparator.comparing(TreeMenuNode::getSort)).collect(Collectors.toList()); treeMenuNode.setChildren(treeMenuNodes); treeMenuNode.getChildren().forEach(t->{ forEach(collect,t); }); } } public static void main(String[] args) { List<ZhField> zhFields = new ArrayList<>(); List<TreeMenuNode> treeNodeList = new ArrayList<>(); //转换数据,这个是前端需要的格式。 zhFields.forEach(t->{ TreeMenuNode treeMenuNode = new TreeMenuNode(); treeMenuNode.setId(t.getId()); treeMenuNode.setParentId(t.getParentId()); treeMenuNode.setName(t.getName()); treeMenuNode.setSort(t.getSort()); treeNodeList.add(treeMenuNode); }); //分组 Map<String, List<TreeMenuNode>> collect = treeNodeList.stream().collect(Collectors.groupingBy(TreeMenuNode::getParentId)); //树形结构 肯定有一个根部，我的这个根部的就是parentId.euqal("0"),而且只有一个就get（"0"） TreeMenuNode treeMenuNode = collect.get("0").get(0); //拼接数据 forEach(collect, treeMenuNode); } }
my
package com.hainei.service.impl.wp.jgzz; import com.hainei.common.constants.BaseConstant; import com.hainei.common.enums.YesOrNo; import com.hainei.common.token.JwtTokenUtil; import com.hainei.common.tree.TreeObject; import com.hainei.common.tree.TreeService; import com.hainei.common.tree.myTree.ToModel; import com.hainei.common.tree.myTree.TreeMenuNode; import com.hainei.common.tree.myTree.ZhField; import com.hainei.mapper.base.BaseUserMapper; import com.hainei.mapper.wp.jgzz.WpJgzzAqglwlMapper; import com.hainei.mapper.wp.sbgl.WpYfbyjlMapper; import com.hainei.pojo.bo.wp.jgzz.WpJgzzAqglwlBO; import com.hainei.pojo.bo.wp.sbgl.WpYfbyBO; import com.hainei.pojo.model.wp.jgzz.WpJgzzAqglwl; import com.hainei.pojo.model.wp.sbgl.WpYfby; import com.hainei.pojo.model.wp.sbgl.WpYfbyjl; import com.hainei.pojo.vo.base.BaseTreeOrganizationWithRolesVO; import com.hainei.pojo.vo.wp.jgzz.WpAqglwlVO; import com.hainei.pojo.vo.wp.sbgl.WpYfbyVO; import com.hainei.service.base.BaseDataTableService; import com.hainei.service.base.BaseOrganizationService; import com.hainei.service.wp.jgzz.WpAqglwlService; import com.hainei.service.wp.zyaqgl.WpZypNumService; import org.apache.commons.collections.CollectionUtils; import org.springframework.beans.BeanUtils; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; import javax.servlet.http.HttpServletRequest; import java.util.*; import java.util.stream.Collectors; /** * Created with IntelliJ IDEA. * User：wq * Date：2021/1/8 * Time: 15:53 * Description: 目标职责 */ @Service @Transactional public class WpAqglwlServiceImpl implements WpAqglwlService { @Autowired private WpJgzzAqglwlMapper jgzzAqglwlMapper; @Autowired private WpYfbyjlMapper wpYfbyjlMapper; @Autowired private HttpServletRequest request; @Autowired private BaseOrganizationService organizationService; @Autowired private BaseDataTableService dataTableService; @Autowired private WpZypNumService zypNumService; @Autowired private BaseUserMapper userMapper; @Override public void addRecord(WpJgzzAqglwlBO wpJgzzAqglwlBO) { String token = request.getHeader(BaseConstant.ACCESS_TOKEN); String userId = JwtTokenUtil.getUserId(token); String id = UUID.randomUUID().toString().replaceAll("-", ""); WpJgzzAqglwl wpJgzzAqglwl = new WpJgzzAqglwl(); BeanUtils.copyProperties(wpJgzzAqglwlBO, wpJgzzAqglwl); wpJgzzAqglwl.setId(id); //wpYfby.setFileNum(zypNumService.getZypNum("AQWJ")); wpJgzzAqglwl.setIsDeleted(YesOrNo.NO.type); wpJgzzAqglwl.setGmtCreatedOn(new Date()); wpJgzzAqglwl.setGmtCreatedBy(userId); //添加数据权限表 Set<String> organizationIdsByUserId = organizationService.getOrganizationIdsByUserId(userId); //3.插入数据权限 dataTableService.insert(organizationIdsByUserId, id); jgzzAqglwlMapper.insertSelective(wpJgzzAqglwl); } @Override public void deleteByIds(List<String> ids) { for (String id : ids) { WpJgzzAqglwl wpJgzzAqglwl = new WpJgzzAqglwl(); wpJgzzAqglwl.setId(id); wpJgzzAqglwl.setIsDeleted(YesOrNo.YES.type); jgzzAqglwlMapper.updateByPrimaryKeySelective(wpJgzzAqglwl); } } @Override public void updateRecord(WpJgzzAqglwlBO wpJgzzAqglwlBO) { String token = request.getHeader(BaseConstant.ACCESS_TOKEN); String userId = JwtTokenUtil.getUserId(token); WpJgzzAqglwl wpJgzzAqglwl = new WpJgzzAqglwl(); wpJgzzAqglwl.setGmtUpdatedBy(userId); BeanUtils.copyProperties(wpJgzzAqglwlBO, wpJgzzAqglwl); jgzzAqglwlMapper.updateByPrimaryKeySelective(wpJgzzAqglwl); } @Override public Map<String,Object> getById(String id) { Map byId = jgzzAqglwlMapper.getById(id); // putWfValue(byId); return byId; } @Override public List<TreeMenuNode> listAll(WpJgzzAqglwlBO wpJgzzAqglwlBO) { String token = request.getHeader(BaseConstant.ACCESS_TOKEN); String userId = JwtTokenUtil.getUserId(token); Collection<TreeObject<WpAqglwlVO>> treeRootList = null; WpAqglwlVO parent =null; TreeMenuNode treeMenuNode = new TreeMenuNode(); wpJgzzAqglwlBO.setGmtCreatedBy(userId); List<WpAqglwlVO> wpAqglwlVOS = jgzzAqglwlMapper.listAll(wpJgzzAqglwlBO); WpAqglwlVO wpAqglwlVO = wpAqglwlVOS.stream().filter(p->p.getIsDeleted()==0).filter(p -> p.getParentId() == null||"".equals(p.getParentId())).collect(Collectors.toList()).get(0); BeanUtils.copyProperties(wpAqglwlVO,treeMenuNode); List<TreeMenuNode> stringListMap = transTree(treeMenuNode, wpAqglwlVOS); return stringListMap; } public List<TreeMenuNode> transTree(TreeMenuNode treeMenuNode1,List<WpAqglwlVO> wpAqglwlVOS) { List<TreeMenuNode> treeNodeList = new ArrayList<>(); //转换数据,这个是前端需要的格式。 wpAqglwlVOS.forEach(t->{ TreeMenuNode treeMenuNode = new TreeMenuNode(); treeMenuNode.setId(t.getId()); treeMenuNode.setParentId(t.getParentId()); treeMenuNode.setManageName(t.getName()); treeMenuNode.setSortIndex(t.getSortIndex()); treeMenuNode.setId(t.getId()); treeMenuNode.setPrincipal(t.getPrincipal()); treeMenuNode.setPrincipalPhone(t.getPrincipalPhone()); treeMenuNode.setRemark(t.getRemark()); treeMenuNode.setSafeDuty(t.getSafeDuty()); treeNodeList.add(treeMenuNode); }); //分组 Map<String, List<TreeMenuNode>> collect = treeNodeList.stream().collect(Collectors.groupingBy(TreeMenuNode::getParentId)); //树形结构 肯定有一个根部，我的这个根部的就是parentId.euqal("0"),而且只有一个就get（"0"） //TreeMenuNode treeMenuNode = collect.get("0").get(0); //拼接数据 List<TreeMenuNode> treeMenuNodes = ToModel.forEach(collect, treeMenuNode1); return treeMenuNodes; } }
TreeMenuNode
package com.hainei.common.tree.myTree; import io.swagger.annotations.ApiModelProperty; import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; import javax.persistence.Column; import javax.persistence.Id; import java.io.Serializable; import java.util.List; import java.util.Map; @Data @AllArgsConstructor @NoArgsConstructor public class TreeMenuNode implements Serializable { @Id private String id; /** * 父节点id */ @Column(name = "parent_id") @ApiModelProperty(value = "父节点id",example = "父节点id") private String parentId; /** * 子节点排序 */ @Column(name = "sort_index") @ApiModelProperty(value = "子节点排序",example = "子节点排序") private Integer sortIndex; /** * 名称 */ @Column(name = "manage_name") @ApiModelProperty(value = "名称",example = "名称") private String manageName; /** * 负责人 */ @ApiModelProperty(value = "负责人",example = "负责人") private String principal; /** * 负责人联系方式 */ @Column(name = "principal_phone") @ApiModelProperty(value = "负责人联系方式",example = "负责人联系方式") private String principalPhone; /** * 备注 */ @ApiModelProperty(value = "备注",example = "备注") private String remark; @ApiModelProperty(value = "安全职责",example = "安全职责") private String safeDuty; // private String name; // private Integer sort; private List<TreeMenuNode> children; private Boolean isAble; /**20180929zhw添加 树的额外属性(至少含有父节点ID:"parentId")**/ private Map<String,Object> attributes; }
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