递归算法的应用-树形结构数据的拼装
树对象：
package com.qkkj.hardwaremgmt.database.resultmap;
import java.util.List;
import com.qkkj.hardwaremgmt.database.beans.SysMenu;
/**
*
* @Title: SysMenuResultMap.java
* @Package com.qkkj.usrmgmt.database.resultmap
* @Description: TODO(用于显示主菜单树)
* @author wangfudong
* @date 2018年5月3日 下午5:30
* @version V1.0
*/
public class SysMenuTreeResultMap extends SysMenu {
private static final long serialVersionUID = -4114812291607390605L;
//主键
private String menuId;
//父级菜单id
private String parentMenuId;
//排序
private Integer menuSort;
//菜单名称
private String menuName;
//菜单路径
private String menuUrl;
//子菜单list
private List<SysMenuTreeResultMap> children;
public String getMenuName() {
return menuName;
}
public void setMenuName(String menuName) {
this.menuName = menuName;
}
public String getMenuUrl() {
return menuUrl;
}
public void setMenuUrl(String menuUrl) {
this.menuUrl = menuUrl;
}
public List<SysMenuTreeResultMap> getChildren() {
return children;
}
public void setChildren(List<SysMenuTreeResultMap> children) {
this.children = children;
}
public String getParentMenuId() {
return parentMenuId;
}
public void setParentMenuId(String parentMenuId) {
this.parentMenuId = parentMenuId;
}
public Integer getMenuSort() {
return menuSort;
}
public void setMenuSort(Integer menuSort) {
this.menuSort = menuSort;
}
public String getMenuId() {
return menuId;
}
public void setMenuId(String menuId) {
this.menuId = menuId;
}
}
递归拼装树：
package com.qkkj.hardwaremgmt.database.service.impl;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.commons.lang.StringUtils;
import org.apache.shiro.cache.Cache;
import org.apache.shiro.cache.ehcache.EhCacheManager;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.qkkj.hardwaremgmt.database.beans.SysUser;
import com.qkkj.hardwaremgmt.database.mapper.SysMenuMapper;
import com.qkkj.hardwaremgmt.database.mapper.SysUserMapper;
import com.qkkj.hardwaremgmt.database.mapper.SysUserRoleMapper;
import com.qkkj.hardwaremgmt.database.resultmap.SysMenuTreeResultMap;
import com.qkkj.hardwaremgmt.database.service.IMenuService;
import com.qkkj.hardwaremgmt.framework.config.SysConstants;
@Service(“menuService”)
public class MenuServiceImpl implements IMenuService {
@Autowired
private SysUserRoleMapper sysUserRoleMapper;
@Autowired
private SysMenuMapper sysMenuMapper;
@Autowired
private SysUserMapper sysUserMapper;
@Autowired
private EhCacheManager ehCacheManager;
/**
* 根据用户权限集合、
* @author wangfd
* @param userId 用户表主键
*/
@Override
public List<SysMenuTreeResultMap> selectMenuTree(Map<String,Object> param) {
// 根据权限集合、应用id查询一级菜单目录
param.put(“parentMenuId”, “0”);
param.put(“userState”, 0);
List<SysMenuTreeResultMap> resultMenuTree = sysMenuMapper.selectMenuTreeByPermissionIds(param);
// 节点为空直接返回、
if (null == resultMenuTree || resultMenuTree.size() == 0) {
return new ArrayList<SysMenuTreeResultMap>();
}
// 根据一级菜单目录、根据权限集合、应用id 层层查找子集放入到children属性中
resultMenuTree = setMenuChildren(param, resultMenuTree);
return resultMenuTree;
}
/**
* 根据用户id查询用户所有菜单权限返回list集合
* @author wangfd
* @param param
*/
@Override
public List<String> selectPermissionIds(Map<String,Object> param) {
return sysMenuMapper.selectPermissionIds(param);
}
/**
* 根据一级菜单目录、用户id、应用id 层层查找子集放入到children属性中(内调方法)
* @author wangfd
* @param userId 用户表主键、根节点主页菜单集合
*/
public List<SysMenuTreeResultMap> setMenuChildren(Map<String,Object> param,List<SysMenuTreeResultMap> resultMenuTree){
for (int i = 0; i < resultMenuTree.size(); i++) {
SysMenuTreeResultMap item = resultMenuTree.get(i);
String parentMenuId = item.getMenuId();
param.put(“parentMenuId”, parentMenuId);
List<SysMenuTreeResultMap> resultMenuChildren = sysMenuMapper.selectMenuTreeByPermissionIds(param);
if (null != resultMenuChildren && resultMenuChildren.size() > 0) {
// 递归
resultMenuChildren = setMenuChildren(param, resultMenuChildren);
// 设置子集
item.setChildren(resultMenuChildren);
resultMenuTree.set(i, item);
}
}
return resultMenuTree;
}
}
