ztree+java后台取数据(包括异步)生成树状图

java小白初用ztree：
ztree的官网上demo已经很详细，最近项目有用到树桩结构，自己就选择了ztree,下面从后台取数据生成树状结构的源码，官网上用到的php.
1.项目jar包：

2.实体类ZtreeNode.java，生成demo中的zNodes:

示例代码：

package com.demo.ztree.entity;public class ZtreeNode {    private String id;    private Integer state;    private String pid;    private String icon;    private String iconClose;    private String iconOpen;    private String name;    private boolean open;    private boolean isParent;    @Override    public String toString() {        StringBuilder sb = new StringBuilder();        sb.append("{id:\"");        sb.append(id);        sb.append("\",pId:\"");        sb.append(pid);        sb.append("\",name:\"");        sb.append(name);        sb.append("\",state:");        sb.append(state);        sb.append(",icon:\"");        sb.append(icon);        sb.append("\",iconClose:\"");        sb.append(iconClose);        sb.append("\",iconOpen:\"");        sb.append(iconOpen);        sb.append("\",open:\"");        sb.append(open);        sb.append("\",isParent:\"");        sb.append(isParent);        sb.append("\"}");        return sb.toString();    }    public String getIcon() {        return icon;    }    public void setIcon(String icon) {        this.icon = icon;    }    public String getIconClose() {        return iconClose;    }    public void setIconClose(String iconClose) {        this.iconClose = iconClose;    }    public String getIconOpen() {        return iconOpen;    }    public void setIconOpen(String iconOpen) {        this.iconOpen = iconOpen;    }    public boolean isOpen() {        return open;    }    public void setOpen(boolean open) {        this.open = open;    }    public String getId() {        return id;    }    public void setId(String id) {        this.id = id;    }    public String getPid() {        return pid;    }    public void setPid(String pid) {        this.pid = pid;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public boolean isIsParent() {        return isParent;    }    public void setIsParent(boolean isParent) {        this.isParent = isParent;    }    public Integer getState() {        return state;    }    public void setState(Integer state) {        this.state = state;    }    public static void main(String[] args) {        ZtreeNode ztree1 = new ZtreeNode();        ztree1.setId("1");        ztree1.setPid("0");        ztree1.setName("顶层节点");        System.out.println(ztree1);    }}

其中，id、pid、isparent必须，其他的根据需求添加
3.在action中给ZtreeNode属性取值，根据业务，在数据库中取相应值，这里我就直接生成一些值：
这里根据取值过程，分为2中方式：
(1).一次性取值，传到页面：
示例代码：

public String showTree() {        for(int i=-1;i<100000;i++){            if(i<0){                ZtreeNode ztree = new ZtreeNode();                ztree.setId("0");                ztree.setName("顶层节点 ");                ztree.setIsParent(true);                ztree.setIcon(icon);                ztree.setIconClose(iconClose);                ztree.setIconOpen(iconOpen);                listTree.add(ztree);            }else{                ZtreeNode ztree = new ZtreeNode();                ztree.setId(""+(i+1));                ztree.setName("级节点");                ztree.setPid(""+i/10);                ztree.setIcon(icon);                ztree.setIconClose(iconClose);                ztree.setIconOpen(iconOpen);                listTree.add(ztree);            }        }        return SUCCESS;    }

(2).异步取值返回页面：
示例代码：

public String getTree() {        return SUCCESS;    }    public String asyncTree() {        String pid = getRequest().getParameter("id");        if(pid==null ||pid.equals("")){            pid="0";            ZtreeNode ztree = new ZtreeNode();            ztree.setId("1");            ztree.setName("顶级节点");            ztree.setIsParent(true);            ztree.setState(1);            ztree.setIcon(icon);            ztree.setIconClose(iconClose);            ztree.setIconOpen(iconOpen);            listTree.add(ztree);        }else{            for(int i=0;i<40;i++){                ZtreeNode ztree = new ZtreeNode();                ztree.setId(pid+i);                ztree.setName(""+pid.length()+"级节点");                ztree.setState(1);                ztree.setIcon(icon);                ztree.setIconClose(iconClose);                ztree.setIconOpen(iconOpen);                if(pid.length()<4){                    ztree.setIsParent(true);                }                listTree.add(ztree);            }        }        json = JSONArray.fromObject(listTree);        return SUCCESS;    }

4.页面
(1).一次性取值，传到页面：
示例代码：

<!doctype html><html><head><meta charset="utf-8"><title>ztree</title><link href="${request.contextPath}/css/zTreeStyle/zTreeStyle.css" rel="stylesheet" type="text/css"><script type="text/javascript" src="${request.contextPath}/js/jquery-1.8.3.js"></script><script type="text/javascript" src="${request.contextPath}/js/jquery.ztree.all-3.5.min.js"></script><script type=text/javascript>     var zNodes = ${listTree};    var setting = {            check: {                enable: true,                chkboxType: {"Y":"s", "N":"ps"}            },            data: {                simpleData: {                    enable: true                }            }        };    $(document).ready(function(){        $.fn.zTree.init($("#treeDemo"), setting, zNodes);    });</script></head><body><div class="zTreeDemoBackground left">        <ul id="treeDemo" class="ztree"></ul></div><body ></html>

(2).异步取值返回页面：
示例代码：

<!doctype html><html><head><meta charset="utf-8"><title>ztree</title><link href="${request.contextPath}/css/zTreeStyle/zTreeStyle.css" rel="stylesheet" type="text/css"><script type="text/javascript" src="${request.contextPath}/js/jquery-1.8.3.js"></script><script type="text/javascript" src="${request.contextPath}/js/jquery.ztree.all-3.5.min.js"></script><script type=text/javascript>var setting = {            view: {                showLine: false,                addDiyDom: addDiyDom            },            async: {                enable: true,                autoParam: ["id"],                url: "${request.contextPath}/asyncTree.action",                dataFilter: filter            },            check: {                enable: true,                chkboxType: {"Y":"s", "N":"ps"}            },            callback: {                onAsyncSuccess: zTreeOnAsyncSuccess            },            data: {                simpleData: {                    enable: true                }            }        };    $(document).ready(function(){        $.fn.zTree.init($("#treeDemo"), setting);    });    var zTree = $.fn.zTree.getZTreeObj("treeDemo");function zTreeOnAsyncSuccess(event, treeId, treeNode, msg) {    if(treeNode==null){        var zTree = $.fn.zTree.getZTreeObj("treeDemo");        nodes = zTree.getNodes();        for (var i=0, l=nodes.length; i<l; i++) {            zTree.expandNode(nodes[i], true, false, false);        }        asyncNodes(zTree.getNodes());         if (!goAsync) {            curStatus = "";         }    }};function asyncNodes(nodes) {        if (!nodes) return;        curStatus = "async";        var zTree = $.fn.zTree.getZTreeObj("treeDemo");        for (var i=0, l=nodes.length; i<l; i++) {            if (nodes[i].isParent && nodes[i].zAsync) {                asyncNodes(nodes[i].children);            } else {                goAsync = true;                zTree.reAsyncChildNodes(nodes[i], "refresh", true);            }        }    }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;        }function addDiyDom(treeId, treeNode) {    var aObj = $("#" + treeNode.tId + "_a");    if ($("#diyBtn_"+treeNode.id).length>0) return;    switch (treeNode.state) {        case 0:            var editStr = "<span id='diyBtn_space_" +treeNode.id+ "' style='color:red;padding-left:5px;'>未审核</span>";            break;        case 1:            var editStr = "<span id='diyBtn_space_" +treeNode.id+ "' style='color:#6495ED;padding-left:5px;'>正常</span>";            break;        case 2:            var editStr = "<span id='diyBtn_space_" +treeNode.id+ "' style='color:#CD2626;padding-left:5px;'>锁定</span>";            break;        default:            var editStr = "<span id='diyBtn_space_" +treeNode.id+ "' style='padding-left:5px;'>未知状态</span>";            break;        }    aObj.append(editStr);}</script></head><body><div class="zTreeDemoBackground left">        <ul id="treeDemo" class="ztree"></ul></div><body ></html>

5.struts.xml配置：

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE struts PUBLIC    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"    "http://struts.apache.org/dtds/struts-2.3.dtd"><struts>    <constant name="struts.devMode" value="true" />    <package name="default-package" extends="json-default">        <result-types>            <result-type name="json" class="org.apache.struts2.json.JSONResult"/>        </result-types>        <interceptors>            <interceptor name="json" class="org.apache.struts2.json.JSONInterceptor"/>        </interceptors>    </package>    <package name="default" namespace="/"  extends="default-package">        <action name="showTree" class="com.demo.ztree.action.HelloAction"            method="showTree">            <result name="success" type="freemarker">/hello.ftl</result>        </action>        <action name="getTree" class="com.demo.ztree.action.HelloAction"            method="getTree">            <result name="success" type="freemarker">asyncZtree.ftl</result>        </action>        <action name="asyncTree" class="com.demo.ztree.action.HelloAction"            method="asyncTree">             <result name="success" type="json">                      <param name="root">json</param>              </result>        </action>    </package></struts>

6.效果图：

7.可以根据自己的业务要求自己选用和改进，这里包含了：
(1)checked框的提交;
(2)异步加载，显示1级节点后，后台自动加载下级节点。