1、生成验证码的工具类
可以直接用
- 将随机生成的验证码保存在session中
public class RandomValidateCodeUtil {
public static final String RANDOMCODEKEY= "RANDOMVALIDATECODEKEY";//放到session中的key
private String randString = "0123456789";//随机产生只有数字的字符串 private String
//private String randString = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生只有字母的字符串
//private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生数字与字母组合的字符串
private int width = 95;// 图片宽
private int height = 25;// 图片高
private int lineSize = 40;// 干扰线数量
private int stringNum = 4;// 随机产生字符数量
private static final Logger logger = LoggerFactory.getLogger(RandomValidateCodeUtil.class);
private Random random = new Random();
/**
* 获得字体
*/
private Font getFont() {
return new Font("Fixedsys", Font.CENTER_BASELINE, 18);
}
/**
* 获得颜色
*/
private Color getRandColor(int fc, int bc) {
if (fc > 255)
fc = 255;
if (bc > 255)
bc = 255;
int r = fc + random.nextInt(bc - fc - 16);
int g = fc + random.nextInt(bc - fc - 14);
int b = fc + random.nextInt(bc - fc - 18);
return new Color(r, g, b);
}
/**
* 生成随机图片
*/
public void getRandcode(HttpServletRequest request, HttpServletResponse response) {
HttpSession session = request.getSession();
// 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(width, height, BufferedImage.TYPE_INT_BGR);
Graphics g = image.getGraphics();// 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
g.fillRect(0, 0, width, height);//图片大小
g.setFont(new Font("Times New Roman", Font.ROMAN_BASELINE, 18));//字体大小
g.setColor(getRandColor(110, 133));//字体颜色
// 绘制干扰线
for (int i = 0; i <= lineSize; i++) {
drowLine(g);
}
// 绘制随机字符
String randomString = "";
for (int i = 1; i <= stringNum; i++) {
randomString = drowString(g, randomString, i);
}
logger.info(randomString);
//将生成的随机字符串保存到session中
session.removeAttribute(RANDOMCODEKEY);
session.setAttribute(RANDOMCODEKEY, randomString);
g.dispose();
try {
// 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) {
logger.error("将内存中的图片通过流动形式输出到客户端失败>>>> ", e);
}
}
/**
* 绘制字符串
*/
private String drowString(Graphics g, String randomString, int i) {
g.setFont(getFont());
g.setColor(new Color(random.nextInt(101), random.nextInt(111), random
.nextInt(121)));
String rand = String.valueOf(getRandomString(random.nextInt(randString
.length())));
randomString += rand;
g.translate(random.nextInt(3), random.nextInt(3));
g.drawString(rand, 13 * i, 16);
return randomString;
}
/**
* 绘制干扰线
*/
private void drowLine(Graphics g) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(13);
int yl = random.nextInt(15);
g.drawLine(x, y, x + xl, y + yl);
}
/**
* 获取随机的字符
*/
public String getRandomString(int num) {
return String.valueOf(randString.charAt(num));
}
}
2、前端页面代码
前端部分代码
- 注意src=“login/getVerify”
代码
<body>
<!--密码-->
<div style="margin-top: 16px">
<input type="password"
autocomplete="off" placeholder="登录密码" name="password" id="password" required maxlength="32"/>
</div>
<!-- 验证码 -->
<div style="margin-top: 17px">
<input type="text"
autocomplete="off" placeholder="验证码" name="verify" id="verify" required maxlength="32"/>
<a href="javascript:void(0);" title="点击更换验证码">
<img id="imgVerify" src="login/getVerify" alt="更换验证码" height="36" width="170" onclick="getVerify(this);">
</a>
</div>
</body>
<!--js中的代码-->
<script type="text/javascript" src="./js/jquery.min.js"></script>
<script>
//获取验证码
/*function getVerify(obj){
obj.src = "login/getVerify?"+Math.random();//原生js方式
}*/
//获取验证码
function getVerify() {
// $("#imgCode").on("click", function() {
$("#imgVerify").attr("src", 'login/getVerify?' + Math.random());//jquery方式
// });
}
function aVerify(){
var value =$("#verify_input").val();
// alert(value);
$.ajax({
async: false,
type: 'post',
url: 'login/checkVerify',
dataType: "json",
data: {
verifyInput: value
},
success: function (result) {
if (result) {
alert("success!");
} else {
alert("failed!");
}
// window.location.reload();
getVerify();
}
});
}
</script>
3、编写Controller以让验证码图片显示在前端
- 前端的src是"login/getVerify"
- 在controller中调用之前写好的验证码图片生成类
@RestController
@RequestMapping("/login")
public class PictureVerify {
/**
* 生成验证码
*/
@RequestMapping(value = "/getVerify")
public void getVerify(HttpServletRequest request, HttpServletResponse response) {
try {
response.setContentType("image/jpeg");//设置相应类型,告诉浏览器输出的内容为图片
response.setHeader("Pragma", "No-cache");//设置响应头信息，告诉浏览器不要缓存此内容
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expire", 0);
RandomValidateCodeUtil randomValidateCode = new RandomValidateCodeUtil();
randomValidateCode.getRandcode(request, response);//输出验证码图片方法
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 校验验证码
*/
@RequestMapping(value = "/checkVerify", method = RequestMethod.POST,headers = "Accept=application/json")
public boolean checkVerify(@RequestParam String verifyInput, HttpSession session) {
try{
//从session中获取随机数
String inputStr = verifyInput;
String random = (String) session.getAttribute("RANDOMVALIDATECODEKEY");
if (random == null) {
return false;
}
if (random.equals(inputStr)) {
return true;
} else {
return false;
}
}catch (Exception e){
return false;
}
}
}
- 这时前端效果图
4、登陆验证
- 登陆验证时从session中取出随机生成时保存的验证码与表单输入的验证码比较就行了，其他的验证业务不是本节重点
