Calculator.jsp：
<%@ 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>制作简易计算器</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">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="servlet/ResultServlet" method="post">
<table>
<tr>
<td>
<label>操作数一：</label>
<input type="text" name="operandOne"/>
</td>
</tr>
<tr>
<td>
<label>操作数二：</label>
<input type="text" name="operandTwo"/>
</td>
</tr>
<tr>
<td>
<label>运算符：</label>
<select name="operator">
<option>+</option>
<option>-</option>
<option>*</option>
<option>/</option>
</select>
</td>
</tr>
<tr>
<td>
<input type="submit" value="计算">
</td>
</tr>
</table>
</form>
</body>
</html>