图片验证码

先写一个codeController

package com.ujy.emp.controller;


import com.ujy.utils.ValidateCode;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Controller
@RequestMapping("/code")
public class CodeController {

    @RequestMapping(value="getCode")
    public void getCode(@RequestParam(value = "time") String time, HttpServletRequest request, HttpServletResponse response) {
        ValidateCode code = new ValidateCode(60, 20, 4, 30, 25, "validateCode");
        code.getCode(request, response);

    }
}

在写一个验证码工具类

package com.ujy.utils;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

/**
 * 验证码工具类
 */
public class ValidateCode {

    private int width = 90;//验证码宽度 默认值：90
    private int height = 40;//验证码高度 默认值：40
    private int codeCount = 4;//验证码个数  默认值：4
    private int lineCount = 19;//混淆线个数  默认值：19
    private int fontSize = 20;//字体大小像素
    //存储session中的key值 默认值："validateCode"
    private String sessionKey = "validateCode";

    public ValidateCode() {
    }

    /**
     * @param width    验证码宽度
     * @param height   验证码高度
     * @param fontSize 字体大小像素
     */
    public ValidateCode(int width, int height, int fontSize) {
        this.width = width;
        this.height = height;
        this.fontSize = fontSize;
    }

    /**
     * @param width      验证码宽度
     * @param height     验证码高度
     * @param fontSize   字体大小像素
     * @param sessionKey 存储session中的key值
     */
    public ValidateCode(int width, int height, int fontSize, String sessionKey) {
        this.width = width;
        this.height = height;
        this.fontSize = fontSize;
        this.sessionKey = sessionKey;
    }

    /**
     * @param width      验证码宽度
     * @param height     验证码高度
     * @param codeCount  验证码个数
     * @param fontSize   字体大小像素
     * @param sessionKey 存储session中的key值
     */
    public ValidateCode(int width, int height, int codeCount, int fontSize, String sessionKey) {
        this.width = width;
        this.height = height;
        this.codeCount = codeCount;
        this.fontSize = fontSize;
        this.sessionKey = sessionKey;
    }

    /**
     * @param width      验证码宽度
     * @param height     验证码高度
     * @param codeCount  验证码个数
     * @param lineCount  混淆线个数
     * @param fontSize   字体大小像素
     * @param sessionKey 存储session中的key值
     */
    public ValidateCode(int width, int height, int codeCount, int lineCount, int fontSize, String sessionKey) {
        this.width = width;
        this.height = height;
        this.codeCount = codeCount;
        this.lineCount = lineCount;
        this.fontSize = fontSize;
        this.sessionKey = sessionKey;
    }


    char[] codeSequence = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
            'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
            'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'};

    /**
     * 具体获取验证码的方法
     *
     * @param time time为时戳,这样的话可以避免浏览器缓存验证码
     * @throws IOException
     */
    public void getCode(HttpServletRequest request, HttpServletResponse response) {
        //定义随机数类
        Random r = new Random();
        //定义存储验证码的类
        StringBuilder builderCode = new StringBuilder();
        //定义画布
        BufferedImage buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        //得到画笔
        Graphics g = buffImg.getGraphics();
        //1.设置颜色,画边框
        g.setColor(Color.gray);
        g.drawRect(0, 0, width, height);
        //2.设置颜色,填充内部
        g.setColor(Color.white);
        g.fillRect(1, 1, width - 2, height - 2);
        //3.设置干扰线
        // g.setColor(Color.gray);
        for (int i = 0; i < lineCount; i++) {
            int _R = (int) Math.floor(Math.random() * 256);
            int _G = (int) Math.floor(Math.random() * 256);
            int _B = (int) Math.floor(Math.random() * 256);
            g.setColor(new Color(_R, _G, _B, 255));
            g.drawLine(r.nextInt(width), r.nextInt(width), r.nextInt(width), r.nextInt(width));
        }
        //4.设置验证码
        g.setColor(Color.blue);
        //4.1设置验证码字体
        g.setFont(new Font("宋体", Font.BOLD | Font.ITALIC, fontSize));
        for (int i = 0; i < codeCount; i++) {
            char c = codeSequence[r.nextInt(codeSequence.length)];
            builderCode.append(c);
            g.drawString(c + "", ((width / codeCount) * i + 2), height * 4 / 5);
        }
        try {
            //5.输出到屏幕
            ServletOutputStream sos = response.getOutputStream();
            ImageIO.write(buffImg, "png", sos);
            //6.保存到session中
            HttpSession session = request.getSession();
            session.setAttribute("" + sessionKey + "", builderCode.toString());
            //7.禁止图像缓存。
            response.setHeader("Pragma", "no-cache");
            response.setHeader("Cache-Control", "no-cache");
            response.setDateHeader("Expires", 0);
            response.setContentType("image/png");
            //8.关闭sos
            sos.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

然后在工具类里面调用

<%@ page language="java"  pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<HTML>
<HEAD>
    <TITLE>欢迎登陆项目平台管理系统</TITLE>
    <META http-equiv=Content-Language content=zh-cn>
    <META http-equiv=Content-Type content="text/html; charset=gb2312">
    <META content="MSHTML 6.00.2800.1611" name=GENERATOR>
    <LINK href="images/css1.css" type=text/css rel=stylesheet>
    <LINK href="images/newhead.css" type=text/css rel=stylesheet>
    <script type="text/javascript" src="${pageContext.request.contextPath}/static/js/jquery-1.7.2.js"></script>

    <script type="text/javascript">
        $(function(){
            $("#validateCode").click(function(){
                $("#validateCode").attr("src","${pageContext.request.contextPath}/code/getCode?time="+(new Date().getTime()));
            });
        });
    </script>
</HEAD>
<BODY bgColor=#eef8e0 leftMargin=0 topMargin=0 MARGINWIDTH="0" MARGINHEIGHT="0">
<form method="post" action="${pageContext.request.contextPath}/emp/login">
    <DIV>
        <TABLE cellSpacing=0 cellPadding=0 width=1004 border=0 align="center">
            <TBODY>
            <TR>
                <TD colSpan=6><IMG height=92 alt="" src="images/crm_1.gif"
                                   width=345></TD>
                <TD colSpan=4><IMG height=92 alt="" src="images/crm_2.gif"
                                   width=452></TD>
                <TD><IMG height=92 alt="" src="images/crm_3.gif" width=207></TD>
            </TR>
            <TR>
                <TD colSpan=6><IMG height=98 alt="" src="images/crm_4.gif"
                                   width=345></TD>
                <TD colSpan=4><IMG height=98 alt="" src="images/crm_5.gif"
                                   width=452></TD>
                <TD><IMG height=98 alt="" src="images/crm_6.gif" width=207></TD>
            </TR>
            <TR>
                <TD rowSpan=5><IMG height=370 alt="" src="images/crm_7.gif"
                                   width=59></TD>
                <TD colSpan=5><IMG height=80 alt="" src="images/crm_8.gif"
                                   width=286></TD>
                <TD colSpan=4><IMG height=80 alt="" src="images/crm_9.gif"
                                   width=452></TD>
                <TD><IMG height=80 alt="" src="images/crm_10.gif" width=207></TD>
            </TR>
            <TR>
                <TD><IMG height=110 alt="" src="images/crm_11.gif" width=127></TD>
                <TD background=images/crm_12.gif colSpan=6>
                    <TABLE id=table1 cellSpacing=0 cellPadding=0 width="98%" border=0>
                        <TBODY>
                        <TR>
                            <TD>
                                <TABLE id=table2 cellSpacing=1 cellPadding=0 width="100%"
                                       border=0>
                                    <TBODY>
                                    <TR>
                                        <span style="color:red">${error}</span>
                                        <TD align=middle width=81><FONT color=#ffffff>用户名：</FONT></TD>
                                        <TD><INPUT class=regtxt title=请填写用户名 maxLength=16
                                                   size=16 value=username name=username></TD>
                                    </TR>
                                    <TR>
                                        <TD align=middle width=81><FONT color=#ffffff>密&nbsp;
                                            码：</FONT></TD>
                                        <TD><INPUT class=regtxt title=请填写密码 type=password
                                                   maxLength=16 size=16 name=password id=pass></TD>
                                    </TR>
                                    <TR>
                                        <TD align=middle width=81><FONT color=#ffffff >验证码：</FONT></TD>
                                        <TD><INPUT  title=请填写验证码 maxLength=50 size=12  name=code  value="${errorMsg}">
　　　　　　　　　　　　　　　　　　　　　　　　　　<span><img id="validateCode" src="${pageContext.request.contextPath}/code/getCode?time="+(new Date().getTime()) ></span></TD>
                                    </TR>
                                    </TBODY>
                                </TABLE>
                            </TD>
                        </TR>
                        </TBODY>
                    </TABLE>
                </TD>
                <TD colSpan=2 rowSpan=2><IMG height=158 alt=""
                                             src="images/crm_13.gif" width=295></TD>
                <TD rowSpan=2><IMG height=158 alt="" src="images/crm_14.gif"
                                   width=207></TD>
            </TR>
            <TR>
                <TD rowSpan=3><IMG height=180 alt="" src="images/crm_15.gif"
                                   width=127></TD>
                <TD rowSpan=3><IMG height=180 alt="" src="images/crm_16.gif"
                                   width=24></TD>
                <TD><input title=登录项目平台管理系统 type=image height=48 alt=""
                           width=86 src="images/crm_17.gif" name="image" ></TD>



                <TD><IMG height=48 alt="" src="images/crm_18.gif" width=21></TD>
                <TD colSpan=2><A><IMG title=关闭页面 height=48 alt=""
                                      src="images/crm_19.gif" width=84 border=0></A></TD>
                <TD><IMG height=48 alt="" src="images/crm_20.gif" width=101></TD>
            </TR>
            <TR>
                <TD colSpan=5 rowSpan=2><IMG height=132 alt=""
                                             src="images/crm_21.gif" width=292></TD>
                <TD rowSpan=2><IMG height=132 alt="" src="images/crm_22.gif"
                                   width=170></TD>
                <TD colSpan=2><IMG height=75 alt="" src="images/crm_23.gif"
                                   width=332></TD>
            </TR>
            <TR>
                <TD colSpan=2><IMG height=57 alt="" src="images/crm_24.gif"
                                   width=332></TD>
            </TR>
            <TR>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=59></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=127></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=24></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=86></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=21></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=28></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=56></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=101></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=170></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=125></TD>
                <TD><IMG height=1 alt="" src="images/spacer.gif" width=207></TD>
            </TR>
            </TBODY>
        </TABLE>
    </DIV>
</form>
</BODY>
</HTML>