zTree异步加载菜单节点--从数据库中查询

来源：互联网发布：java生命周期包括编辑：程序博客网时间：2024/04/28 08:43

项目需要一个动态菜单，随手做了一个demo，留着以后参考。

JSP+Servlet从oracle中查找菜单显示出来，废话不说，直接上图

最终效果图

代码：

1.index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>ztree demo</title>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<link rel="stylesheet" type="text/css" href="./css/demo.css">
<link rel="stylesheet" type="text/css" href="./css/zTreeStyle/zTreeStyle.css">
<script type="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">
var setting = {
data: {
simpleData: {
enable: true
}
},
async: {
enable: true,
url:"tree.action",
autoParam:["id=pid"],
dataFilter: filter //异步返回后经过Filter
},
callback:{
asyncSuccess: zTreeOnAsyncSuccess,//异步加载成功
asyncError: zTreeOnAsyncError, //加载错误
beforeClick:beforeClick //捕获单击节点之前的事件回调函数
}
};

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 beforeClick(treeId,treeNode){
if(!treeNode.isParent){
alert("请选择父节点");
return false;
}else{
zTree.expandNode(treeNode);
return true;
}
}
function zTreeOnAsyncError(event, treeId, treeNode){
alert("异步加载失败!");
}
function zTreeOnAsyncSuccess(event, treeId, treeNode, msg){

}

var zNodes=[];

$(document).ready(function(){
$.fn.zTree.init($("#tree"), setting, zNodes);
});
</script>
<body>
<ul id="tree" class="ztree"></ul>
</body>
</html>

2.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>servlet</servlet-name>
<servlet-class>servlet.TestServlet</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>servlet</servlet-name>
<url-pattern>*.action</url-pattern>
</servlet-mapping>


<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>

3.TestServlet 没有处理请求路径，因为只是一个demo，.action结尾的请求都处理了

package servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServlet;

import com.alibaba.fastjson.JSON;

import dao.MenuDao;
import entity.Menu;

@SuppressWarnings("serial")
public class TestServlet extends HttpServlet {

@SuppressWarnings("unchecked")
@Override
public void service(ServletRequest request, ServletResponse response) throws ServletException, IOException {
System.out.println("pid:"+request.getParameter("pid"));
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
int pid = 0;
MenuDao dao = new MenuDao();
List<Menu> menus = new ArrayList<Menu>();
if(request.getParameter("pid")==null||"".equals(request.getParameter("pid"))){
try {
menus = dao.getRoot();
} catch (Exception e) {
e.printStackTrace();
}
}else{
pid = Integer.parseInt(request.getParameter("pid"));
try {
menus = dao.getNextNodes(pid);
} catch (Exception e) {
e.printStackTrace();
}
}

String str = JSON.toJSONString(menus);
System.out.println("str:"+str);
out.print(str);

}
}

4.dao

package dao;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import util.DBUtil;
import entity.Menu;
@SuppressWarnings("rawtypes")
public class MenuDao {

public List getRoot() throws Exception {
Connection conn = DBUtil.getConnection();
Statement st = conn.createStatement();
ResultSet rs =st.executeQuery("select * from dept where pid is null");
Menu menu ;
List<Menu> menus = new ArrayList<Menu>();
while(rs.next()){
menu = new Menu();
menu.setId(rs.getInt("id"));
menu.setPid(rs.getInt("pid"));
menu.setName(rs.getString("name"));
if("1".equals(rs.getString("isParent"))){
menu.setIsParent(true);
}else{
menu.setIsParent(false);
}
menus.add(menu);
}
for(int i =0;i<menus.size();i++){
System.out.println(menus.get(i).getName());
}
return menus;
}

public List getNextNodes(int pid) throws Exception{
Connection conn = DBUtil.getConnection();
Statement st = conn.createStatement();
ResultSet rs =st.executeQuery("select * from dept where pid ="+pid);
Menu menu ;
List<Menu> menus = new ArrayList<Menu>();
while(rs.next()){
menu = new Menu();
menu.setId(rs.getInt("id"));
menu.setPid(rs.getInt("pid"));
menu.setName(rs.getString("name"));
if("1".equals(rs.getString("isParent"))){
menu.setIsParent(true);
}else{
menu.setIsParent(false);
}
menus.add(menu);
}
for(int i =0;i<menus.size();i++){
System.out.println(menus.get(i).getName());
}
return menus;

}

}

5.bean

package entity;

public class Menu {

private int pid;
private int id;
private String name;
private boolean isParent;
public int getPid() {
return pid;
}
public void setPid(int pid) {
this.pid = pid;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public boolean getIsParent() {
return isParent;
}
public void setIsParent(boolean isParent) {
this.isParent = isParent;
}

}

6.dbutil

package util;

import java.sql.Connection;
import java.sql.DriverManager;

public class DBUtil {

public static Connection getConnection() throws Exception{
Connection conn = null;
Class.forName("oracle.jdbc.driver.OracleDriver");//加入oracle的驱动，“”里面是驱动的路径

String url = "jdbc:oracle:thin:@localhost:1521:orcl";// 数据库连接，oracle代表链接的是oracle数据库；thin:@MyDbComputerNameOrIP代表的是数据库所在的IP地址（可以保留thin:）；1521代表链接数据库的端口号；ORCL代表的是数据库名称

String UserName = "root";// 数据库用户登陆名 ( 也有说是 schema 名字的 )

String Password = "root";// 密码

conn = DriverManager.getConnection(url, UserName, Password);
return conn;
}

public static void main(String[] args) throws Exception {
System.out.println(getConnection());
}
}

工程截图

用到了两个jar,

oracle数据库截图,