在eclipse环境下实现简单的表单提交（servlet）

servlet做的。正好java老师上课讲了一点，回来复现了一下。
实现的是从html提交表单，java收到并进行RSA加密的相关计算。
重点是提醒自己的form表单里的action填写。（两个文件在同一包下）
html文件里的ajax方法是未完成的

servlet_java.java文件

package com.example.demo;


import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.Random;

public class servlet_java extends HttpServlet {
    private static final long serialVersionUID = 1L;
    public static String obvtext;
    public static String ciphertext;
    static Random ra = new Random();


    public servlet_java() {
        super();
        // TODO Auto-generated constructor stub
    }

 
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        response.setContentType("text/html;charset=UTF-8");
        response.getWriter().append("Served at: ").append(request.getContextPath());
        PrintWriter out = response.getWriter();

        obvtext = request.getParameter("obvtext");
        ciphertext = request.getParameter("ciphertext");
        BigInteger p = new BigInteger("106697219132480173106064317148705638676529121742557567770857687729397446898790451577487723991083173010242416863238099716044775658681981821407922722052778958942891831033512463262741053961681512908218003840408526915629689432111480588966800949428079015682624591636010678691927285321708935076221951173426894836169");
        BigInteger q = new BigInteger("144819424465842307806353672547344125290716753535239658417883828941232509622838692761917211806963011168822281666033695157426515864265527046213326145174398018859056439431422867957079149967592078894410082695714160599647180947207504108618794637872261572262805565517756922288320779308895819726074229154002310375209");

        RSA rsa = new RSA();
        // ���ɹ�Կ˽Կ'''
        // pubkey, selfkey = gen_key(p, q)
        //���������P,Q
        System.out.println("��һ��----------------------------------------------------");
        System.out.println("");
        System.out.println("素数p为:" + q);
        System.out.println("素数q为:" + p);

        BigInteger[][] keys = rsa.genKey(p, q); //公钥对为，n,e��n,d
        BigInteger[] pubkey = keys[0];
        //System.out.println("Keys[0]:"+(pubkey[0]));
        BigInteger[] selfkey = keys[1];
        //System.out.println("Keys[1]:"+(pubkey[1]));
        //System.out.println("N=(q-1)*(p-1),NΪ:"+pubkey[0]);
        System.out.println();
        BigInteger m = new BigInteger("1");//����

     		   /* System.out.println("������Aliceѡȡ������M:");
     	    	String contents2=input.next();  //������ĸ����  */

        //ת��Ϊm
        String contents2 = obvtext;
        String mid = change.stringToAscii(contents2);
        m = new BigInteger("" + mid);
        //m�Ѿ�ת�����˴�����
        System.out.println("Alice选择的明文M为:" + m);
        System.out.println();


        BigInteger c = rsa.encrypt(m, pubkey);  //���ܼ���õ�����C!!!!!!!!!!!!!
        BigInteger r = new BigInteger("1");//��ʼ��
        System.out.println("Trudy开始攻击---------------------------------");
     		    /*
     		    System.out.println("������Trudyѡ���rΪ:");
     		    String contents3=input.next();  //������ĸ���� */
        //ת��Ϊm
        String contents3 = ciphertext;
        String mid1 = change.stringToAscii(contents3);
        r = new BigInteger("" + mid1);

        System.out.println("Trudy选择的r为:" + c);
        System.out.println();
        System.out.println("Alice开始解密------------------------------");
        System.out.println("C'=Cr^e mod N");

        BigInteger C1 = new Exponentiation().expModemul(r, pubkey[1], c, p.multiply(q));
        System.out.println(" C'=Cr^e mod N,解得c'为=" + C1);

        BigInteger Mr = rsa.decrypt(C1, selfkey);  //���ܼ���õ�����Mr!!!!!!!!!!!!!!!!
        //System.out.println(" C'=Cr^e mod N,����C'^d=(Mr)^d,����d="+selfkey[1]);
        System.out.println("C'=Cr^e mod N,又有C'^d=(Mr)^de,解得Mr为:" + Mr);
        System.out.println("");
        System.out.println("Alice发送Mr给Trudy---------------------------");
        BigInteger M = Mr.divide(r);

        String last = change.asciiToString(M.toString());
        System.out.println("Trudy知道r,又知道Mr，由M=Mr/r,解得明文M为:" + last);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }


    public BigInteger[][] genKey(BigInteger p, BigInteger q) {
        BigInteger n = p.multiply(q);
        System.out.println("N=(q-1)*(p-1),NΪ:" + n);
        BigInteger fy = p.subtract(BigInteger.ONE).multiply(q.subtract(BigInteger.ONE));
        BigInteger e = new BigInteger("3889");//ѡȡ�˹�Կe,��֪��
        // generate d
        BigInteger a = e;
        BigInteger b = fy;
        BigInteger[] rxy = new gcd().extGcd(a, b);//����õ�d��
        BigInteger r = rxy[0];
        BigInteger x = rxy[1];
        BigInteger y = rxy[2];

        BigInteger d = x;
        System.out.println("��ԿeΪ:" + e);
        System.out.println("˽ԿdΪ:" + d);
        // ��Կ  ˽Կ
        return new BigInteger[][]{{n, e}, {n, d}};
    }

    public BigInteger encrypt(BigInteger m, BigInteger[] pubkey) { //����
        BigInteger n = pubkey[0];
        BigInteger e = pubkey[1];

        BigInteger c = new Exponentiation().expMode(m, e, n);
        return c;
    }

    public BigInteger decrypt(BigInteger c, BigInteger[] selfkey) {  //����
        BigInteger n = selfkey[0];
        BigInteger d = selfkey[1];

        BigInteger m = new Exponentiation().expMode(c, d, n);
        return m;
    }

    //��ʮ����ת���ɶ�����
    public static int shier(int i) {
        int num = i;
        int a = 0;//����һ��int��������
        int b = 0;
        int c = 0;
        while (num != 0) {
            a = num % 2;
            num = num / 2;
            b++;
            for (int i1 = 0; i1 < b; i1++) {
                a = a * 10;
            }
            c += a;
        }
        return c;
    }

    @SuppressWarnings("unused")
    private static BigInteger pow(int intValue) {
        // TODO Auto-generated method stub
        return null;
    }

    @SuppressWarnings("unused")
    private static int multiply(BigInteger r, BigInteger r2) {
        // TODO Auto-generated method stub
        return 0;
    }

    @SuppressWarnings("unused")
    private static int intValue(BigInteger bigInteger) {
        // TODO Auto-generated method stub
        return 0;
    }


}

test.html

<!DOCTYPE html>
<html>
<head>
    <script src="jquery.js"></script>
    <meta charset="UTF-8">
    <title>RSA算法</title>

    <style type="text/css">
        p {
            text-align: center;
            font-family: 微软雅黑;
            font-weight: bold;
        }

        span {
            text-align: center;

        }

        div {
            width: 220px;
            margin-top: 260px;
            margin-bottom: 100px;
            margin-left: 40px;
            margin-right: 40px;

        }
    </style>
    <script type="text/javascript">
        var request;

        function Dom() {
            var mtext = document.form1.obvtext.value;
            var ctext = document.form1.ciphertext.value;
            if (mtext == "") {
                alert("明文不可为空");
            }
            if (mtext != "" && ctext == "") {
                alert("密文不可为空");
            }
            document.getElementById("result").innerHTML = "<p>Alice选取的明文为:</p>" + mtext + "<br />" + "<p>Trudy选取的r为:</p>" + ctext + "<br />";
        }

        document.forms[0].target = "rfFrame";

        function ajax_submit() {
            $.ajax({
                async: false,    //表示请求是否异步处理
                contentType:'application/x-www-form-urlencoded;charset=utf-8',
                type: "post",    //请求类型
                url: "/return_text",//请求的 URL地址
                dataType: "json",//返回的数据类型
                data: "",
                success: function (data) {
                    console.log(data);  //在控制台打印服务器端返回的数据
                },
                error: function (data) {
                    alert("error" + data);
                }
            });

        }
    </script>
</head>
<body>

<!-- 初始按钮 -->
<!-- 信息输出框 随输出改变大小-->
<div style="width:auto; display:inline-block !important; display:inline;float:left;border:solid #4c4c4c">
    <p>N,p,q等参数输出:</p>
</div>

<!-- 提交框 -->
<div style="float:left;border:solid #4c4c4c ;height:266px;margin-top: 210px ;">
    <form name="form1" style="text-align: center;" target="rfFrame" method="post" action="package名字/servlet_java">
        <iframe id="rfFrame" name="rfFrame" src="about:blank" style="display:none;"></iframe>
        <p style="">Alice进行加密</p>

        <span>请输入Alice选取的明文M:</span>
        <input type="text" name="obvtext" id="otext" style="margin-top: 20px">
        <p>Trudy进行攻击</p>

        <span>请输入Trudy选取的r:</span>
        <input type="text" name="ciphertext" id="ctext" style="margin-top: 20px;">

        <input type="submit" type="button" value="提交" style="margin-top:6px;display: flex;margin-left: 86px;"
               onClick="Dom();ajax_submit()">
    </form>
</div>

<!-- 信息输出框 -->
<div style="height:142px;float:left;border:solid #4c4c4c;text-align: center;">

    <span style="font-size: 14px" id="result"></span>

</div>
</body>

</html>