JavaBea+JSP、Servlet+JSP、JavaBean+Servlet+JSP实现复数运算器-蒲公英云

JavaBea+JSP

代码：

JavaBea

JSP

Servlet+JSP

代码：

Servlet：

JSP：

JavaBean+Servlet+JSP

代码：

JavaBean：

Servlet：

JSP：

JavaBea+JSP

代码：

JavaBea

public class Complex {
    private double a;
    private double b;
    public Complex(double a, double b) {
        this.a = a;
        this.b = b;
    }
    public Complex add(Complex c) {
        return new Complex(this.a + c.a, this.b + c.b);
    }
    public Complex subtract(Complex c) {
        return new Complex(this.a - c.a, this.b - c.b);
    }
    public Complex multiply(Complex c) {
        double a = this.a * c.a - this.b * c.b;
        double b = this.a * c.b + this.b * c.a;
        return new Complex(a, b);
    }
    public Complex divide(Complex c) {
        double denominator = c.a * c.a + c.b * c.b;
        double a = (this.a * c.a + this.b * c.b) / denominator;
        double b = (this.b * c.a - this.a * c.b) / denominator;
        return new Complex(a, b);
    }
    public double getA() {
        return a;
    }
    public void setA(double a) {
        this.a = a;
    }
    public double getB() {
        return b;
    }
    public void setB(double b) {
        this.b = b;
    }
}

JSP

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ page import="com.dong.demo4.bean" %>
<%@ page import="com.dong.demo4.bean.Complex" %>
<html>
<head>
<title>复数计算器</title>
</head>
<body>
<h1>复数计算器</h1>
<form method="post">
<label>第一个复数：</label>
<input type="text" name="num1">
<label>+</label>
<input type="text" name="num2">i
<br>
<label>第二个复数：</label>
<input type="text" name="num3">
<label>+</label>
<input type="text" name="num4">i
<br>
<label>运算符：</label>
<select name="operator">
<option value="+">加法</option>
<option value="-">减法</option>
<option value="*">乘法</option>
<option value="/">除法</option>
</select>
<br>
<br>
<input type="submit" name="submit" value="计算">
</form>
<% if (request.getParameter("submit") != null) { %>
<br>
<h2>计算结果：</h2>
<% double num1 = Double.parseDouble(request.getParameter("num1")); %>
<% double num2 = Double.parseDouble(request.getParameter("num2")); %>
<% double num3 = Double.parseDouble(request.getParameter("num3")); %>
<% double num4 = Double.parseDouble(request.getParameter("num4")); %>
<% Complex c1 = new Complex(num1, num2); %>
<% Complex c2 = new Complex(num3, num4); %>
<%
        String op = request.getParameter("operator");
        Complex result = null;
        switch (op) {
        case "+":
        result = c1.add(c2);
        break;
        case "-":
        result = c1.subtract(c2);
        break;
        case "*":
        result = c1.multiply(c2);
        break;
        case "/":
        result = c1.divide(c2);
        break;
default:
        break;
        }
        %>
<p><%= result.getReal() %><%= result.getImaginary() >= 0 ? "+" : "-" %><%= Math.abs(result.getImaginary()) %>i</p>
<% } %>
</body>
</html>

Servlet+JSP

代码：

Servlet：

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/complexCalculatorServlet ")
public class ComplexCalculatorServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    protected void doPost(HttpServletRequest request,
                          HttpServletResponse response) throws ServletException, IOException {
        double num1 = Double.parseDouble(request.getParameter("num1"));
        double num2 = Double.parseDouble(request.getParameter("num2"));
        double num3 = Double.parseDouble(request.getParameter("num3"));
        double num4 = Double.parseDouble(request.getParameter("num4"));
        String operator = request.getParameter("operator");
        double resultA = 0;
        double resultB = 0;
        switch (operator) {
            case "+":
                resultA = num1 + num3;
                resultB = num2 + num4;
                break;
            case "-":
                resultA = num1 - num3;
                resultB = num2 - num4;
                break;
            case "*":
                resultA = num1 * num3 - num2 * num4;
                resultB = num1 * num4 + num2 * num3;
                break;
            case "/":
                double denominator = num3 * num3 + num4 * num4;
                resultA = (num1 * num3 + num2 * num4) / denominator;
                resultB = (num2 * num3 - num1 * num4) / denominator;
                break;
            default:
                break;
        }
        // 将结果存储到 request 对象中
        request.setAttribute("resultA", resultA);
        request.setAttribute("resultB", resultB);
        // 转发请求到 JSP 页面
        request.getRequestDispatcher("/result.jsp").forward(request, response);
    }
}

JSP：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>复数计算器</title>
</head>
<body>
<h1>复数计算器</h1>
<form action="/complexCalculatorServlet"
        method="post">
<label>第一个复数：</label>
<input type="text" name="num1">
<label>+</label>
<input type="text" name="num2">i
<br>
<label>第二个复数：</label>
<input type="text" name="num3">
<label>+</label>
<input type="text" name="num4">i
<br>
<label>运算符：</label>
<select name="operator">
<option value="+">加法</option>
<option value="-">减法</option>
<option value="*">乘法</option>
<option value="/">除法</option>
</select>
<br>
<br>
<input type="submit" name="submit" value="计算">
</form>
<% if (request.getAttribute("resultA") != null) { %>
<br>
<h2>计算结果：</h2>
<p><%= request.getAttribute("resultA") %><%= (Double)request.getAttribute("resultB") >= 0 ? "+" : "-" %><%= Math.abs((Double)request.getAttribute("resultB")) %>i</p>
<% } %>
</body>
</html>

JavaBean+Servlet+JSP

代码：

JavaBean：

package com.dong.demo1;
/**
 * 模式三：JavaBean+Servlet+JSP
 */
/**
 * 复数类---JavaBean类
 */
public class Complex {
    private double real;//实部
    private double imaginary;//虚部
    public Complex() {
    }
    public Complex(double real, double imaginary) {
        this.real = real;
        this.imaginary = imaginary;
    }
    /**
     * @Discription 加法
     * @author Lidong
     * @param other
     * @return
     */
    public Complex add(Complex other) {
        return new Complex(this.real + other.real, this.imaginary + other.imaginary);
    }
    /**
     * @Discription 减法
     * @author Lidong
     * @param other
     * @return
     */
    public Complex subtract(Complex other) {
        return new Complex(this.real - other.real, this.imaginary - other.imaginary);
    }
    /**
     * @Discription 乘法
     * @author Lidong
     * @param other
     * @return
     */
    public Complex multiply(Complex other) {
        double realPart = this.real * other.real - this.imaginary * other.imaginary;
        double imaginaryPart = this.real * other.imaginary + this.imaginary * other.real;
        return new Complex(realPart, imaginaryPart);
    }
    /**
     * @Discription 除法
     * @author Lidong
     * @param other
     * @return
     * @throws ArithmeticException
     */
    public Complex divide(Complex other) throws ArithmeticException {
        double denominator = other.real * other.real + other.imaginary * other.imaginary;
        if (denominator == 0) {
            throw new ArithmeticException("Divide by zero!");
        }
        double realPart = (this.real * other.real + this.imaginary * other.imaginary) / denominator;
        double imaginaryPart = (-this.real * other.imaginary + this.imaginary * other.real) / denominator;
        return new Complex(realPart, imaginaryPart);
    }
    public double getReal() {
        return real;
    }
    public void setReal(double real) {
        this.real = real;
    }
    public double getImaginary() {
        return imaginary;
    }
    public void setImaginary(double imaginary) {
        this.imaginary = imaginary;
    }
}

Servlet：

package com.dong.demo1;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;
@WebServlet("/complexCalc")
public class ComplexCalcServlet extends HttpServlet {
   // private static final long serialVersionUID = 1L;
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //获取第一个复数
        String real1Str = request.getParameter("real1");
        String imaginary1Str = request.getParameter("imaginary1");
        //获取第二个复数
        String real2Str = request.getParameter("real2");
        String imaginary2Str = request.getParameter("imaginary2");
        //获取运算符：{ +、 —— 、* 、/ }
        String operator = request.getParameter("operator");
        double real1 = Double.parseDouble(real1Str);
        double imaginary1 = Double.parseDouble(imaginary1Str);
        double real2 = Double.parseDouble(real2Str);
        double imaginary2 = Double.parseDouble(imaginary2Str);
        Complex complex1 = new Complex(real1, imaginary1);
        Complex complex2 = new Complex(real2, imaginary2);
        Complex result;
        switch (operator) {
            case "+":
                result = complex1.add(complex2);
                break;
            case "-":
                result = complex1.subtract(complex2);
                break;
            case "*":
                result = complex1.multiply(complex2);
                break;
            case "/":
                try {
                    result = complex1.divide(complex2);
                } catch (ArithmeticException e) {
                    request.setAttribute("error", e.getMessage());
                    request.getRequestDispatcher("/complex.jsp").forward(request, response);
                    return;
                }
                break;
            default:
                throw new IllegalArgumentException("无效的操作!");
        }
        request.setAttribute("result", result);
        request.getRequestDispatcher("/result.jsp").forward(request, response);
    }
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request,response);
    }
}

JSP：

输入页面：

<%—
Created by IntelliJ IDEA.
User: CaptainDong
Date: 2023/5/31
Time: 10:42
To change this template use File | Settings | File Templates.
—%>
<%@ page contentType=”text/html;charset=UTF-8” language=”java” %>
<%@ taglib prefix=”c” uri=”http://java.sun.com/jsp/jstl/core“ %>
<!DOCTYPE html>

复数计算器

复数计算器

请输入第一个复数:

+ i

请输入第二个复数:

+ i

请选择一个运算符:

结果如下:

${result.real} + ${result.imaginary}i

错误:

${error}
结果展示：

<%@ page import=”com.dong.demo1.Complex” %>
<%@ taglib prefix=”c” uri=”http://java.sun.com/jsp/jstl/core“ %>
<%—
Created by IntelliJ IDEA.
User: CaptainDong
Date: 2023/5/31
Time: 11:07
To change this template use File | Settings | File Templates.
—%>
<%@ page contentType=”text/html;charset=UTF-8” language=”java” %>

运算结果

结果如下:

<%
Complex result= (Complex) request.getAttribute(“result”);
String s1=result.getReal()+” “+”+”+”(“+result.getImaginary()+” “+”i”+”)”;
%>
<%=s1%>

结果如下:

${result.real} + ${result.imaginary}i

错误信息:

${error}