FastJson+Ztree：根据数据库层级表生成目录树

来源：互联网发布：西安行知教育编辑：程序博客网时间：2024/04/27 21:02

目标：

从数据库层级表：

到目录树结构的实现全过程：

中间产生的JSON数据：

实现途径：

配置jdbc数据源，从数据库中读取以上的层级表，将所有的记录存到ArrayList中，利用fastJson将其解析成JSON数据格式(序列化)，而后利用ztree生成目录树结构。

工具版本：

fastJson1.1.9, ztree3.5, jdk1.7, struts1.2, jquery1.4, oracle9i

实现步骤：

index.jsp(访问http://localhost:8088/fastjson/index.jsp)

<%@ page language="java"import="java.util.*" pageEncoding="ISO-8859-1"%>
<%
String path = request.getContextPath();
String basePath =request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
         <metahttp-equiv="pragma" content="no-cache">
         <metahttp-equiv="cache-control" content="no-cache">
         <metahttp-equiv="expires" content="0">
         <metahttp-equiv="keywords"content="keyword1,keyword2,keyword3">
         <metahttp-equiv="description" content="This is my page">
         
</head>
<body>
<%
       response.sendRedirect("getJson.do");
%>
</body>
</html>

GetJsonAction.java（ActionServlet）

package com.nns.struts.action;
importjavax.servlet.http.HttpServletRequest;
importcom.nns.util.Menu;
importcom.alibaba.fastjson.*;
importjava.util.ArrayList;
importjava.util.List;
importjavax.servlet.http.HttpServletResponse;
importorg.apache.struts.action.Action;
importorg.apache.struts.action.ActionForm;
importorg.apache.struts.action.ActionForward;
importorg.apache.struts.action.ActionMapping;
importjava.sql.Connection;
importjava.sql.ResultSet;
importjava.sql.SQLException;
importjava.sql.Statement;
importjavax.naming.Context;
importjavax.naming.InitialContext;
importjavax.naming.NamingException;
importjavax.sql.DataSource;
publicclass GetJsonAction extends Action {
publicActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequestrequest, HttpServletResponse response) {

List<Menu> m = new ArrayList<Menu>();
                   //连接数据源
                   Connectionconn = null;
                   try {
                            Context ctx= new InitialContext();
                            ContextcompNamingContext = (Context)ctx.lookup("java:comp/env");
                            DataSourceds = (DataSource)compNamingContext.lookup("jdbc/user1DataSource");
                            try {
                                     conn =ds.getConnection();
                                     if(conn==null){
                                               System.out.println("获取数据源连接失败");
                                     } else {
                                               Statement st= conn.createStatement();
                                               String sql ="select * from jsontree";
                                               ResultSet rs= st.executeQuery(sql);
                                               Stringid="",pid="",name="",t="";
                                               while(rs.next()){
                                                       id=rs.getString("id");
                                                       pid=rs.getString("pid");
                                                       name=rs.getString("name");
                                                       t=rs.getString("t");
                                                       //System.out.println("=="+id+"=="+pid+"=="+name+"=="+t);
                                                       Menu m1 =new Menu();
                                                       m1.setId(id);
                                                       m1.setPid(pid);
                                                       m1.setName(name);
                                                       m1.setT(t);
                                                       m.add(m1);
                                               }
                                     }
                            } catch(SQLException e) {
                                     e.printStackTrace();
                            }
                   } catch(NamingException e) {
                            e.printStackTrace();
                   } finally{
                            if(conn!=null){
                                     try {
                                               conn.close();
                                     } catch(SQLException e) {
                                               e.printStackTrace();
                                     }
                                     conn=null;
                            }
                   }
//序列化过程
String jsonString = JSON.toJSONString(m);
System.out.println("序列化(将javabean对象转换成json数据)");
System.out.println(jsonString.replaceAll("pid", "pId"));
request.setAttribute("jsondata", jsonString.replaceAll("pid", "pId"));

//反序列化测试
List<Menu> mcs = new ArrayList<Menu>();
mcs = JSON.parseArray(jsonString, Menu.class);
System.out.println("反序列化(将json数据还原成javabean对象)");
Iterator<Menu> iter = mcs.iterator();
while(iter.hasNext()){
Menu mu = iter.next();
System.out.println("id="+mu.getId()+";pid="+mu.getPid()+";name="+mu.getName()+";t="+mu.getT());
}
           return mapping.findForward("success");
         }
}

success.jsp(显示目录树页面)：

<%@ page language="java"import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath =request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'goto.jsp' starting page</title>
         <metahttp-equiv="pragma" content="no-cache">
         <metahttp-equiv="cache-control" content="no-cache">
         <metahttp-equiv="expires" content="0">
         <metahttp-equiv="keywords" content="keyword1,keyword2,keyword3">
         <metahttp-equiv="description" content="This is my page">
         <scripttype="text/javascript" src="js/jquery-1.4.4.min.js"></script>
<script type="text/javascript"src="js/jquery.ztree.core-3.5.js"></script>
<script type="text/javascript" src="js/jquery.ztree.excheck-3.5.js"></script>
         <linkrel="stylesheet" href="css/demo.css"type="text/css" />
<link rel="stylesheet"href="css/zTreeStyle/zTreeStyle.css" type="text/css" />
         <SCRIPTtype="text/javascript">
                   var setting = {
                            data:{
                                     key:{
                                               title:"t"
                                     },
                                     simpleData:{
                                               enable:true,
                                               idKey:"id",
                                               pIdKey:"pId",
                                               rootPId:0
                                     }
                            },
                            callback:{
                                     onClick:onClick
                            }
                   };
                   var zNodes =<%=(String)request.getAttribute("jsondata")%>;
                   functionbeforeClick(treeId, treeNode, clickFlag) {
                   }
                   function onClick(event,treeId, treeNode, clickFlag) {
                            //treeId是目录树的id，即treeDemo
                            //alert('目录树的id:'+treeId);
                            //alert('名称：'+treeNode.name);
                            alert('父节点id：'+treeNode.pId);
                            alert('节点id：'+treeNode.id);
                            //alert('选中标示:'+clickFlag);
                   }
                   $(document).ready(function(){
                            $.fn.zTree.init($("#treeDemo"),setting, zNodes);
                   });
                   //-->
         </SCRIPT>
</head>
<body>
   <div>
   <ul id="treeDemo" class="ztree">
   </ul></div>
</body>
</html>

Menu.java（工具类javabean）：

package com.nns.util;
import java.util.ArrayList;
import java.util.List;
public class Menu {
private String id = ""; //当前节点id
private String pid = ""; //父级节点 id
private String name = "";//节点名称
private String t=""; // 提示
//private List<Menu> menus = new ArrayList<Menu>();
//可根据需要添其他属性
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 getPid() {
return pid;
}
public void setPid(String pid) {
this.pid = pid;
}
public String getT() {
return t;
}
public void setT(String t) {
this.t = t;
}

/*
public List<Menu> getMenus() {
return menus;
}
public void setMenus(List<Menu> menus) {
this.menus = menus;
}
*/

}