JAVA 树形子父级菜单递归 JSON 格式

约定不等于承诺〃 2023-06-17 11:51 2阅读 0赞

package tree;  
  
import java.util.List;  
  
/\*\*  
\*  
\* @author cenguocheng  
\* 137544496@qq.com  
\* 2018-7-24  
\*/  
public class Menu \{  
// 菜单id  
private String id;  
// 菜单名称  
private String name;  
// 父菜单id  
private String parentId;  
// 菜单url  
private String url;  
// 菜单图标  
private String icon;  
// 菜单顺序  
private int order;  
// 子菜单  
private List<Menu> childMenus;  
  
public Menu(String id, String name, String parentId) \{  
super();  
this.id = id;  
this.name = name;  
this.parentId = parentId;  
\}  
  
@Override  
public String toString() \{  
return "Menu \[id=" + id + ", name=" + name + ", parentId=" + parentId  
\+ ", url=" + url + ", icon=" + icon + ", order=" + order  
\+ ", childMenus=" + childMenus + "\]";  
\}  
  
public String getId() \{  
return id;  
\}  
public void setId(String id) \{  
this.id = id;  
\}  
public String getName() \{  
return name;  
\}  
public void setName(String name) \{  
this.name = name;  
\}  
public String getParentId() \{  
return parentId;  
\}  
public void setParentId(String parentId) \{  
this.parentId = parentId;  
\}  
public String getUrl() \{  
return url;  
\}  
public void setUrl(String url) \{  
this.url = url;  
\}  
public String getIcon() \{  
return icon;  
\}  
public void setIcon(String icon) \{  
this.icon = icon;  
\}  
public int getOrder() \{  
return order;  
\}  
public void setOrder(int order) \{  
this.order = order;  
\}  
public List<Menu> getChildMenus() \{  
return childMenus;  
\}  
public void setChildMenus(List<Menu> childMenus) \{  
this.childMenus = childMenus;  
\}  
  
\}  
package tree;  
  
import java.util.ArrayList;  
import java.util.HashMap;  
import java.util.List;  
import java.util.Map;  
  
import com.alibaba.fastjson.JSON;  
/\*\*  
\*  
\* @author cenguocheng  
\* 137544496@qq.com  
\* 2018-7-24  
\*/  
public class TestTree \{  
  
/\*\*  
\* 初始化数据  
\* @return  
\*/  
public static List<Menu> initData()\{  
List<Menu> treeData = new ArrayList<Menu>();  
treeData.add(new Menu("1","1","0"));  
treeData.add(new Menu("2","2","1"));  
treeData.add(new Menu("3","3","1"));  
treeData.add(new Menu("4","4","2"));  
treeData.add(new Menu("5","5","0"));  
treeData.add(new Menu("6","6","2"));  
treeData.add(new Menu("7","7","2"));  
treeData.add(new Menu("8","8","3"));  
treeData.add(new Menu("9","9","10"));  
treeData.add(new Menu("10","10","6"));  
treeData.add(new Menu("11","11","7"));  
return treeData;  
\}  
  
/\*\*  
\* 子菜单递归  
\* @param id  
\* @param rootMenu  
\* @return  
\*/  
private static List<Menu> getChild(String id, List<Menu> rootMenu) \{  
// 子菜单  
List<Menu> childList = new ArrayList<>();  
for (Menu menu : rootMenu) \{  
// 遍历所有节点，将父菜单id与传过来的id比较  
if (menu.getParentId().equals(id)) \{  
childList.add(menu);  
\}  
\}  
  
// 把子菜单的子菜单再循环一遍  
for (Menu menu : childList) \{  
menu.setChildMenus(getChild(menu.getId(), rootMenu));// 递归  
\}  
  
// 判断递归结束  
if (childList.size() == 0) \{  
return null;  
\}  
return childList;  
\}  
  
/\*\*  
\* @param args  
\*/  
public static void main(String\[\] args) \{  
// TODO Auto-generated method stub  
List<Menu> treeData = initData(); // 原始数据  
  
// 查看结果  
for (Menu menu : treeData) \{  
//System.out.println(menu.toString());  
\}  
  
List<Menu> menuList = new ArrayList<Menu>(); // 树递归  
  
// 先找到所有的一级菜单  
for (int i = 0; i < treeData.size(); i++) \{  
// 一级菜单父ID为0  
if (treeData.get(i).getParentId().equals("0")) \{  
menuList.add(treeData.get(i));  
\}  
\}  
  
// 为一级菜单设置子菜单，getChild是递归调用的  
for (Menu menu : menuList) \{  
menu.setChildMenus(getChild(menu.getId(), treeData));  
\}  
  
Map<String,Object> jsonMap = new HashMap<String,Object>();  
jsonMap.put("menu", menuList);  
System.out.println(JSON.toJSONString(jsonMap));  
  
buildMenu(menuList);  
System.out.println(str);  
\}  
  
  
/\*\*  
\* 遍历菜单  
\* @param arr  
\* @return  
\*/  
public static String str = "";  
public static String buildMenu(List<Menu> arr)\{  
  
for(int i=0;i<arr.size();i++)\{  
str += "<li>";  
str += "<a href='javascript:;'>" +  
"<cite>"+arr.get(i).getName()+"</cite>" +  
"<i class='iconfont nav\_right'>"+arr.get(i).getIcon()+"</i>" +  
"</a>";  
//存在子菜单 递归  
if(arr.get(i).getChildMenus() != null && arr.get(i).getChildMenus().size() > 0)\{  
str += "<ul>";  
buildMenu(arr.get(i).getChildMenus()); // 递归  
str += "</ul>";  
\}  
str += "</li>";  
\}  
  
return str;  
\}  
  
  
\}  
运行结果：

\{  
"menu": \[  
\{  
"childMenus": \[  
\{  
"childMenus": \[  
\{  
"id": "4",  
"name": "4",  
"order": 0,  
"parentId": "2"  
\},  
\{  
"childMenus": \[  
\{  
"childMenus": \[  
\{  
"id": "9",  
"name": "9",  
"order": 0,  
"parentId": "10"  
\}  
\],  
"id": "10",  
"name": "10",  
"order": 0,  
"parentId": "6"  
\}  
\],  
"id": "6",  
"name": "6",  
"order": 0,  
"parentId": "2"  
\},  
\{  
"childMenus": \[  
\{  
"id": "11",  
"name": "11",  
"order": 0,  
"parentId": "7"  
\}  
\],  
"id": "7",  
"name": "7",  
"order": 0,  
"parentId": "2"  
\}  
\],  
"id": "2",  
"name": "2",  
"order": 0,  
"parentId": "1"  
\},  
\{  
"childMenus": \[  
\{  
"id": "8",  
"name": "8",  
"order": 0,  
"parentId": "3"  
\}  
\],  
"id": "3",  
"name": "3",  
"order": 0,  
"parentId": "1"  
\}  
\],  
"id": "1",  
"name": "1",  
"order": 0,  
"parentId": "0"  
\},  
\{  
"id": "5",  
"name": "5",  
"order": 0,  
"parentId": "0"  
\}  
\]  
\}