一个简单的登录，POST表单提交时报错，403 bad or missing token！

<form id="formInput" action="check.jhtml" method="POST">

    <div class="main"  style="margin-top:100px;">
    <label class="errorLabel" style="color: red;padding-left:14.5%; padding-top:20px">[#if error != null]${error}[/#if]</label>
    <div class="container">
    <div class="form-group">
        <input type="text" placeholder="输入用户名" id="username" name="username" maxlength="20">
        <label for="username" id="errorName" class="errorLabel" style="color: red;"></label>
    </div>
    <div class="form-group">
        <input type="password" placeholder="输入密码" id="password"  name="password" maxlength="11">
        <label for="password" id="errorPsw" class="errorLabel" style="color: red;"></label>
    </div>
    <div class="submit-group">
        <button id="btnSumbit">登录</button>
    </div>
    </div> 
    </div>
  </div>

</form>

<script type="text/javascript">
var $username = $("#username");
    var $password = $("#password");
    var $errorName = $("#errorName");
    var $errorPsw = $("#errorPsw");

//提交时，验证用户密码是否正确
$("#formInput").submit(function(){
if($username.val() == ""){
$errorName.text("登录名不能为空!");
return false;
}if($password.val() == ""){
$errorPsw.text("密码不能为空!");
return false;
}
return true;
});
</script>

经过不断排查，发现并不是网上说的加上<meta http-equiv="content-type" content="text/html; charset=utf-8" />就可以了，

而是页面中少引用了两个js文件：

<script type="text/javascript" src="/js/jquery-1.9.1.js"></script>
<script type="text/javascript" src="/js/common.js"></script>