JQuery ztree 异步加载实践

本来要做一个文件目录浏览界面，需要遍历所有的文件和目录，很显然一次性读取时很费时费力的一件事情。 因此就需要做异步加载.... 不过网上的几篇帖子还挺坑的！原始参考：JQuery异步加载实例，相对来说这篇博客还算规整！ springMVC中中文乱码问题：解决办法

准备工作

1 JQuery ZTree，下载地址

　　复制其中的JS和CSS即可，其实没必要引那么多，用什么引什么就可以。

2 需要fastJSON,用来转换JSON对象，下载地址

　　我下载JAR包后，引入到Eclipse中总是报找不到class错误。

解决办法：把jar包放在WEB-INF/lib下即可。

代码实例

index.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
    <link rel="stylesheet" href="resources/css/demo.css" type="text/css">
    <link rel="stylesheet" href="resources/css/zTreeStyle/zTreeStyle.css" type="text/css">
    <script type="text/javascript" src="resources/js/jquery-1.4.4.min.js"></script>
    <script type="text/javascript" src="resources/js/jquery.ztree.core-3.5.js"></script>
    
</head>
<body>
    <div class="zTreeDemoBackground left">
        <ul id="treeDemo" class="ztree"></ul>
    </div>
    <SCRIPT type="text/javascript">
        var setting = {  
                data: {  
                    simpleData: {  
                        enable: true  
                    }  
                } ,
                async: {
                    enable: true,
                    url:"/TestZTree/test",
                    autoParam:["id", "name", "level"],
                    otherParam:{"otherParam":"zTreeAsyncTest"},
                    dataFilter: filter
                }
        };  
        function filter(treeId, parentNode, childNodes) {
            if (!childNodes) return null;
            for (var i=0, l=childNodes.length; i<l; i++) {
                childNodes[i].name = childNodes[i].name.replace(/.n/g, '.');
            }
            return childNodes;
        }
        var zNodes =[  
            { id:1, pId:0, name:"parentNode 1", open:true},  
            { id:11, pId:1, name:"parentNode 11",isParent:true},  
            { id:111, pId:11, name:"leafNode 111"},  
            { id:112, pId:11, name:"leafNode 112"},  
            { id:12, pId:1, name:"parentNode 12",isParent:true},  
            { id:121, pId:12, name:"leafNode 121"},  
            { id:13, pId:1, name:"parentNode 13", isParent:true},  
            { id:2, pId:0, name:"parentNode 2", isParent:true}  
        ];  
  
        $(document).ready(function(){  
            $.fn.zTree.init($("#treeDemo"), setting, zNodes);  
        });  
    </SCRIPT>
</body>
</html>

testServlet.java

package com.test;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;

public class testServlet extends HttpServlet{
    @Override  
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {  
        doPost(request, response);  
    }  
  
    @Override  
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {  
        String id = request.getParameter("id");  
        String name = request.getParameter("name");  
        String level = request.getParameter("level");  
        String otherParam = request.getParameter("otherParam");  
        System.out.println(id + "|" + name + "|" + level + "|" + otherParam);  
          
        List<HashMap<String,Object>> list = new ArrayList<HashMap<String,Object>>();  
        for(int i = 0; i < 5; i++){  
            HashMap<String,Object> hm = new HashMap<String,Object>();   //最外层，父节点             
            hm.put("id",id+i);//id属性  ，数据传递    
            hm.put("name", id+i); //name属性，显示节点名称    
            hm.put("pId", id);  
              
            list.add(hm);  
        }  
        response.getWriter().write(JSON.toJSONString(list));  
    }  
}

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
    xmlns="http://java.sun.com/xml/ns/javaee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
    http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
  <display-name></display-name>
  <servlet>
    <servlet-name>testServlet</servlet-name>
    <servlet-class>com.test.testServlet</servlet-class>
  </servlet>

  <servlet-mapping>
    <servlet-name>testServlet</servlet-name>
    <url-pattern>/test</url-pattern>
  </servlet-mapping>
      
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

运行效果