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RandomValidateCode.java,生成二维码的核心代码
package main.java.com.smart.common;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.springframework.stereotype.Component;
@Component
public class RandomValidateCode {
/**
* 1)生成代码
*
* @return
*/
public static String createValidateCode(int size) {
String seed = "1234567890qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM";
int len = seed.length();
char[] p = new char[size];//定义随机代码的长度
for(int i = 0; i < size; i++){
p[i] = seed.charAt((int)Math.floor(Math.random() * len));
}
return new String(p);
}
private final Random random = new Random();
private final String randString = "123456789ABCDEFGHIJKLMNPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";// 随机产生的字符串
private final int width = 135;//图片宽
private final int height = 40;//图片高
private final int lineSize = 50;//干扰线数量
private final int stringNum = 4;//随机产生字符数量
private final int fontSize = 30;//
/**
* 生成随机图片
*/
public void getRandcode(HttpServletRequest request, HttpServletResponse response){
HttpSession session = request.getSession();
// 1、BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类
BufferedImage image = new BufferedImage(this.width, this.height, BufferedImage.TYPE_INT_BGR);
// 2、产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作
Graphics g = image.getGraphics();
g.fillRect(0, 0, this.width, this.height);
g.setFont(new Font("Times New Roman", Font.ROMAN_BASELINE, this.fontSize));
g.setColor(this.getRandColor(110, 133));//随机颜色
// 3、绘制干扰线
for (int i = 0; i <= this.lineSize; i++) {
this.drawLine(g);
}
// 4、绘制随机字符
String randomString = "";
for (int i = 1; i <= this.stringNum; i++) {
randomString = this.drawString(g, randomString, i);
}
session.removeAttribute(Constants.RANDOM_CODE_KEY);//5、移除原本的属性值
session.setAttribute(Constants.RANDOM_CODE_KEY, randomString);//6、添加新的属性值
// System.out.println(randomString);
g.dispose();//7、手动销毁图形对象,以免占用系统资源
try {
// 8、禁止图像缓存。
response.setHeader("Pragma", "no-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
// 9、将内存中的图片通过流动形式输出到客户端
ImageIO.write(image, "JPEG", response.getOutputStream());
}
catch (Exception e) {
e.printStackTrace();
}
}
/**
* 获取随机的字符
*/
public String getRandomString(int num) {
return String.valueOf(this.randString.charAt(num));
}
/**
* 绘制干扰线
*/
private void drawLine(Graphics g) {
int x = this.random.nextInt(this.width);
int y = this.random.nextInt(this.height);
int xl = this.random.nextInt(13);
int yl = this.random.nextInt(15);
g.drawLine(x, y, x + xl, y + yl);
}
/**
* 绘制字符串
*/
private String drawString(Graphics g, String randomString, int i) {
g.setFont(this.getFont());
g.setColor(new Color(this.random.nextInt(155), this.random.nextInt(123), this.random.nextInt(176)));
String rand = String.valueOf(this.getRandomString(this.random.nextInt(this.randString.length())));
randomString += rand;
g.translate(this.random.nextInt(3), this.random.nextInt(3));
g.drawString(rand, (this.width / this.stringNum - 14) * i, this.height - 7);
return randomString;
}
/**
* 获得字体
*/
private Font getFont() {
return new Font("Times New Roman", Font.CENTER_BASELINE, this.fontSize);
}
/**
* 获得颜色
*/
private Color getRandColor(int fc, int bc) {
if (fc > 255) {
fc = 255;
}
if (bc > 255) {
bc = 255;
}
int r = fc + this.random.nextInt(bc - fc - 16);
int g = fc + this.random.nextInt(bc - fc - 14);
int b = fc + this.random.nextInt(bc - fc - 18);
return new Color(r, g, b);
}
}
ToolController.java
package main.java.com.smart.web;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import main.java.com.smart.common.RandomValidateCode;
@Controller
public class ToolController {
@Resource
RandomValidateCode code;
/**
* 向服务器请求一个验证码
*
* @param request
* @param response
*/
@RequestMapping("/vcode")
public void vcode(HttpServletRequest request, HttpServletResponse response){
code.getRandcode(request, response);
}
}
ulogin.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>登录用户桌面</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" href="${pageContext.request.contextPath}/static/css/public.css" type="text/css">
<link rel="stylesheet" href="${pageContext.request.contextPath}/static/css/allprivate.css" type="text/css">
</head>
<body>
<script type="text/javascript">
var i = 1;
function changecode(){
document.getElementById('vcode').src="vcode.html?v=" + (i++);
}
</script>
<div id="container">
<div class="ulogin">
<p class="ulogin_head"><span>用户登录</span></p>
<form class="ulogin_form" onsubmit="return checkUserName()" method="POST" action="user/doLogin.html">
<table>
<tr>
<td>账号</td>
<td><input type="text" name="uid" id="uid" class="ulogin_form_1"
required v-model="uid_text" :placeholder="tip_uid" :maxlength="userlength"></td>
</tr>
<tr>
<td>密码</td>
<td><input type="password" name="password" id="pwd" class="ulogin_form_1"
required v-model="pwd_text" :placeholder="tip_pwd" :maxlength="pwdlength"></td>
</tr>
<tr>
<td><input type="text" name="vcode"></td>
<td><input id="vcode" type="image" src="vcode.html" onclick="changecode()"></td>
</tr>
</table>
<p class="ulogin_form_line"></p>
<input type="submit" name="登录" class="ulogin_form_2">
<input type="reset" name="重置" class="ulogin_form_2">
</form>
</div>
<div><a href="user/register.html">用户注册</a></div>
<font color="red">${verror}</font>
<font color="red">${error}</font>
</div>
<script src="${pageContext.request.contextPath}/static/js/vue.min.js"></script>
<script src="${pageContext.request.contextPath}/static/js/login.js"></script>
</body>
</html>
最后通过对比用户输入的和服务器保存的验证码,判断用户是否正确输入验证码
String sessionCode = (String)request.getSession().getAttribute(Constants.RANDOM_CODE_KEY);
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