struts怎么运行不了

<%@ 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 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">


<script type="text/javascript" src="jquery-1.7.1.js"></script>
<script type="text/javascript">
$(function(){
$("#button").click(function(){
var re=/[\u4e00-\u9fa5]/;
var username=$("#username").val();
var password=$("password").val();
alert(username+password);
if(username==""){
$("#label1").html("用户名不能为空");
$("#username").focus();
return false;
}else if(re.test(username)){
$("#label1").html("用户名不能是中文");
$("#username").focus();
return false;
}
else if(password==""){
$("#label2").html("密码不能为空");
$("#password").focus();
return false;
}
else if(password!=6){
$("#label2").html("密码必须为6位");
$("#password").focus();
return false;
}
else {
$.ajax({
url : "front/test_json!testjson",
type : "post",
data : {'username':username,'password':password},
success:function(data){
alert(data.msg);
},
});
}
});
});

</script>
</head>

<body>
姓名:
<input type="text" id="username">
<label id="label1">
用户名不能为中文
</label>
<br>
<br />
密码:
<input type="text" id="password">
<label id="label2">
密码为6个字符
</label>
<br>
<br>
<input type="button" value="提交" id="button">
</body>
</html>

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>

<package name="default" namespace="/front" extends="json-default">

<action name="test_json" class="com.bdqn.Demo.person">

<result name="testjson" type="json">/success.jsp</result>
</action>
</package>
</struts>

package com.bdqn.Demo;

import org.apache.struts2.ServletActionContext;

public class person {
String msg;

public String getMsg() {
return msg;
}

public void setMsg(String msg) {
this.msg = msg;
}
public String testjson(){

String name = ServletActionContext.getRequest().getParameter("username");
System.out.println(name);

if(name.equals("hejin")){
msg = "用户名已经存在";
}else{
msg = "该用户名可以使用!";
}

return "testjson";
}

}
--------------------编程问答--------------------

报的啥错啊。。。 --------------------编程问答--------------------

错误是什么... --------------------编程问答-------------------- 1，你的action没有继承ActionSupport
2，这地方不用ajax请用form表单
3，struts 的ajax不是这样用的

补充：Java ,  Eclipse