2-8自由编程
你好老师，我的按钮显示的是这样的。没有真实结果出现，怎么么回事啊？谢谢
package com.wei.ajaxl;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.alibaba.fastjson.JSON;
import com.wei.ajax.New;
/**
* Servlet implementation class ShowServlet
*/
@WebServlet("/show")
public class ShowServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public ShowServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
List list=new ArrayList();
List list1=new ArrayList();
List list2=new ArrayList();
List list4=new ArrayList();
list.add(new Employee("小红"));
list.add(new Employee("小明"));
list.add(new Employee("小白"));
list1.add(new Job("职员") );
list1.add(new Job("经理") );
list2.add(new Apartment("人事部"));
list2.add(new Apartment("技术部"));
list2.add(new Apartment("无线事业部"));
list4.add(list);
list4.add(list1);
list4.add(list2);
String json= JSON.toJSONString(list4);
response.setContentType("text/html;charset=UTF-8");
response.getWriter().println(json);
}
}
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<input type="button" name="employee1" id="employee" value="员工列表">
<input type="button" name="job1" id="job" value="职位列表">
<input type="button" name="depar1" id="depar" value="部门列表">
<br>
<div id="showDiv1">
</div>
<script>
//1.创建xmlhttprequest
document.getElementById("employee").onclick = function() {
var xmlhttp;
if (window.XMLHttpRequest) {
xmlhttp = new XMLHttpRequest();
} else {
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.open("GET", "/FirstServlett/show", true);
xmlhttp.send();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
var j = xmlhttp.responseText;
console.log(j);
var json = JSON.parse(j);
var n=json[0];
document.getElementById("showDiv1").innerHTML = n;
}
}
}
document.getElementById("job").onclick = function() {
var xmlhttp;
if (window.XMLHttpRequest) {
xmlhttp = new XMLHttpRequest();
} else {
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.open("GET", "/FirstServlett/show", true);
xmlhttp.send();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
var j = xmlhttp.responseText;
console.log(j);
var json = JSON.parse(j);
var n = json[1];
document.getElementById("showDiv1").innerHTML = n;
}
}
}
//第三个div
document.getElementById("depar").onclick = function() {
var xmlhttp;
if (window.XMLHttpRequest) {
xmlhttp = new XMLHttpRequest();
} else {
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.open("GET", "/FirstServlett/show", true);
xmlhttp.send();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
var j = xmlhttp.responseText;
console.log(j);
var json = JSON.parse(j);
var n = json[2];
document.getElementById("showDiv1").innerHTML = n;
}
}
}
</script>
</body>
</html>
13
收起
正在回答 回答被采纳积分+1
1回答
好帮手慕小脸
2021-04-13 16:02:07
同学你好，代码存在如下问题：
1、由于同学没有贴出实体类，这里猜测同学实体类代码没有实现序列化，建议将其补全
2、在html中需引入js文件，如下：
3、无需创建三个实体类对象，这里同学可以直接定义一个对象，里面包含三个属性即可，如:
Servlet类中代码简化如下：
4、展示数据这里应使用循环，不然得到的数据是有误的
其他同理
参考代码如下：
@WebServlet("/show")
public class ShowServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public ShowServlet() {
super();
}
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
List<Employee> list = new ArrayList();
list.add(new Employee("小红","职员","人事部"));
list.add(new Employee("小明","经理","技术部"));
list.add(new Employee("小白","助理","无线事业部"));
String json = JSON.toJSONString(list);
response.setContentType("text/html;charset=UTF-8");
System.out.println(json);
response.getWriter().println(json);
}
}
document.getElementById("employee").onclick = function() {
var xmlhttp;
if (window.XMLHttpRequest) {
xmlhttp = new XMLHttpRequest();
} else {
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
console.log(xmlhttp);
xmlhttp.open("GET", "/ajax/show", true);
xmlhttp.send();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
var j = xmlhttp.responseText;
console.log(j);
var json = JSON.parse(j);
console.log(json);
var html = "";
for (var i = 0; i < json.length; i++) {
html = html +json[i].emp + "<br/>";
}
document.getElementById("showDiv1").innerHTML = html;
}
}
}
祝学习愉快~
java工程师2020版
- 参与学习 人
- 提交作业 9393 份
- 解答问题 16556 个
综合就业常年第一，编程排行常年霸榜，无需脱产即可学习，北上广深月薪过万 无论你是未就业的学生还是想转行的在职人员，不需要基础，只要你有梦想，想高薪
了解课程
恭喜解决一个难题，获得1积分~
来为老师/同学的回答评分吧
0 星