如何使用Java实现树形菜单对象

本篇内容主要讲解"如何使用Java实现树形菜单对象"，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习"如何使用Java实现树形菜单对象"吧!

1、SysMenu

package com.zy.shiro.domain;import com.baomidou.mybatisplus.annotation.IdType;import com.baomidou.mybatisplus.annotation.TableField;import com.baomidou.mybatisplus.annotation.TableId;import com.fasterxml.jackson.annotation.JsonInclude;import io.swagger.annotations.ApiModel;import lombok.Data;import lombok.EqualsAndHashCode;import lombok.experimental.Accessors;import java.io.Serializable;import java.util.ArrayList;import java.util.List;/** * sys_menu * @author  */@Data@EqualsAndHashCode(callSuper = false)@Accessors(chain = true)@ApiModel(value="SysMenu对象", description="菜单管理")public class SysMenu implements Serializable {    @TableId(value = "menu_id", type = IdType.AUTO)    private Long menuId;    /**     * 父菜单id，父菜单为0     */    private Long parentId;    /**     * 菜单名称     */    private String menuName;    /**     * 菜单url     */    private String url;    /**     * 授权(多个用逗号分隔，如：user:list,user:create)     */    private String permisions;    /**     * 类型   0：目录   1：菜单   2：按钮     */    private Integer menuType;    /**     * 菜单图标     */    private String icon;    /**     * 排序     */    private Integer orderNum;    @TableField(exist = false)    private List list;//    @JsonInclude(value = JsonInclude.Include.NON_EMPTY)//    private List child=new ArrayList<>();    private static final long serialVersionUID = 1L;}

2、TreeNode

package com.zy.common.tree;import com.fasterxml.jackson.annotation.JsonInclude;import lombok.AllArgsConstructor;import lombok.Data;import lombok.NoArgsConstructor;import sun.reflect.generics.tree.Tree;import java.io.Serializable;import java.util.ArrayList;import java.util.List;@Data@AllArgsConstructor@NoArgsConstructorpublic class TreeNode implements Serializable {    private Integer id;    private Integer pid;    private String title;    private String icon;    private String href;    private String target;    private Boolean spread;    @JsonInclude(value = JsonInclude.Include.NON_EMPTY)    private List child=new ArrayList<>();    /**     * 登陆成功之后系统主而需要的菜单树的json对象构造器     * @param id     * @param pid     * @param title     * @param icon     * @param href     * @param target     * @param spread     */    public TreeNode(Integer id, Integer pid, String title, String icon, String href, String target, Boolean spread) {        this.id = id;        this.pid = pid;        this.title = title;        this.icon = icon;        this.href = href;        this.target = target;        this.spread = spread;    }    public  static class TreeNodeBuilder{        /**         *         * @param treeNodes 要生成有层级关系的源数据         * @param topId  最顶层的pid 根节点的pid         * @return         */        public static List build(List treeNodes,Integer topId){            List nodes=new ArrayList<>();            for (TreeNode n1 : treeNodes) {                if(n1.getPid().equals(topId)){                    //说明n1节点是                    nodes.add(n1);                }                for (TreeNode n2 : treeNodes) {                    if(n2.getPid().equals(n1.getId())){                        //说明n2是n1的子节点 应该放到n1的clild里面                        n1.getChild().add(n2);                    }                }            }            return nodes;        }    }}

3、SysMenuServiceImpl

根据用户id查询该用户所拥有的菜单

 // 1 用户的id 查询角色    List