EasyUI的一星权限

一星权限目前市场已经没有人再用了，但是也是所有高星权限的一个基础
这个图的理解应该很简单，就是从用户表中拿到menuId,再到menu菜单表中进行查询，但是怎么把查出来的list数据转成json数据就有一点点难理解了。代码如下

package com.fairy.dao;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.fairy.entity.TreeNode;
import com.fairy.util.JsonBaseDao;
import com.fairy.util.JsonUtil;
import com.fairy.util.PageBean;
import com.fairy.util.StringUtils;

public class MenuTreeDao extends JsonBaseDao{

	public List<Map<String, Object>> menuList(Map<String, String[]> paramMap,PageBean pageBean) throws InstantiationException, IllegalAccessException, SQLException{
		String sql="select * from t_easyui_menu where true";
		String menuId=JsonUtil.getparamMap(paramMap, "Menuid");
		if (StringUtils.isNotBlank(menuId)) {
			sql+=" and parentid="+menuId;
		}else{
			sql+=" and parentid=-1";
		}
		return super.executeQuery(sql, null);
		
	}
	
	private void mapToTreeNode(Map<String, Object> map,TreeNode treeNode) throws InstantiationException, IllegalAccessException, SQLException {
		treeNode.setId(map.get("Menuid").toString());
		treeNode.setText(map.get("Menuname").toString());
		treeNode.setAttributes(map);
		
		//treeNode.setChildren(children);
		
		Map<String, String[]> paramMap=new HashMap<>();
		//把当前节点当作父id，查出所有子节点
		paramMap.put("Menuid", new String[] {treeNode.getId()});
		List<Map<String, Object>> menuList=this.menuList(paramMap, null);
		List<TreeNode> treeNodeList=new ArrayList<>();
		mapListToTreeNodeList(menuList, treeNodeList);
		treeNode.setChildren(treeNodeList);
		
	}
	
	
	public void mapListToTreeNodeList(List<Map<String, Object>> list,List<TreeNode> treeNodeList) throws InstantiationException, IllegalAccessException, SQLException {
		TreeNode treeNode=null;
		for (Map<String, Object> map : list) {
			treeNode=new TreeNode();
			mapToTreeNode(map, treeNode);
			treeNodeList.add(treeNode);
		}
	}
	
	/**
	 * 此方法的返回值才是符合easyui树形的组建所需要的json格式
	 * @param paramMap
	 * @param pageBean
	 * @return
	 * @throws InstantiationException
	 * @throws IllegalAccessException
	 * @throws SQLException
	 */
	public List<TreeNode> getEndList(Map<String, String[]> paramMap,PageBean pageBean) throws InstantiationException, IllegalAccessException, SQLException{
		List<Map<String, Object>> menuList=this.menuList(paramMap, null);
		List<TreeNode> treeNodeList=new ArrayList<>();
		mapListToTreeNodeList(menuList, treeNodeList);
		return treeNodeList;
		
	}
}

调用时的方法：

	List<TreeNode> endList = this.mtDao.getEndList(req.getParameterMap(), null);
			ObjectMapper om=new ObjectMapper();
			ResponseUtil.write(resp, om.writeValueAsString(endList));

ResponseUtil是个方法类：

package com.fairy.util;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.http.HttpServletResponse;

public class ResponseUtil {

	public static void write(HttpServletResponse resp,Object obj) throws IOException {
		resp.setContentType("text/html;charset=utf-8");
		PrintWriter out = resp.getWriter();
		out.println(obj.toString());
		out.flush();
		out.close();
		
	}
}