index.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<title>計算</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="stylesheet" href="css/bootstrap.min.css"/>
<link rel="stylesheet" href="css/style.css"/>
<script src="js/jquery-3.4.1.min.js"></script>
<script src="js/script.js"></script>
</head>
<body>
<div>
<br>
<h1 class="text-center text-success">數學計算</h1>
<hr>
<br>
<form class="form-inline text-center">
數字1： <input type="text" name="num1" value="100" class="form-control">
<br><br>
數字2： <input type="text" name="num2" value="20" class="form-control">
<br><br>
<input type="submit" formaction="as" value="加" class="btn btn-sm btn-danger">
<input type="submit" formaction="ss" value="減" class="btn btn-sm btn-warning">
<input type="submit" formaction="ms" value="乘" class="btn btn-sm btn-primary">
<input type="submit" formaction="ds" value="除" class="btn btn-sm btn-success">
</form>
<br><br><br><br><br>
<div class="text-center">
<a href="img/dlam.png" id="pic">
<img src="img/dlam.png" alt="多啦a夢圖片" title="多啦a夢" width="309" height="190">
</a>
</div>
</div>
</body>
</html>
AdditionServlet
package com.qdu.servlet;
import com.qdu.service.MathService;
import com.qdu.service.impl.MathServiceImpl;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* 處理兩數相加的請求的servlet
*
* @author NIIT
*/
//MVC Model-View-Controller
@WebServlet("/as")
public class AdditionServlet extends HttpServlet {
MathService mathService=new MathServiceImpl();
//doGet方法處理get請求
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1. 獲取請求參數
double a=Double.parseDouble(req.getParameter("num1"));
double b=Double.parseDouble(req.getParameter("num2"));
//2. 調用真正的業務邏輯,實現請求處理
double result=mathService.add(a, b);
//3. 跳轉頁面
//jsp中四個範圍：page,request,session,application
//如果只是想把數據共享給下個頁面，可以直接將數據作爲屬性添加到請求對象中
//然後轉發請求即可
req.setAttribute("jieguo", result);
req.getRequestDispatcher("/result.jsp").forward(req, resp);
}
}
result.jsp
<h4 class="text-danger">結果: ${jieguo} </h4>
<711的隨機整數
Random ran = new Random();
return ran.nextInt(711); //<711的隨機整數
百分制 ran.nextInt(711)*100/710