一、导入依赖
<!-- 验证码 -->
<dependency>
<groupId>com.github.penggle</groupId>
<artifactId>kaptcha</artifactId>
<version>2.3.2</version>
<exclusions>
<exclusion>
<artifactId>javax.servlet-api</artifactId>
<groupId>javax.servlet</groupId>
</exclusion>
</exclusions>
</dependency>或
<dependency>
<groupId>com.google.code.kaptcha</groupId>
<artifactId>kaptcha</artifactId>
<version>2.3</version>
</dependency>kaptcha 是一个很有用的验证码生成工具，由于它有许多可配置项，所以用它可以简单快捷的生成各式各样的验证码。
二、使用步骤
前端部分相关代码展示
<div class="login-center clearfix row">
<div class="col-xs-6">
<input type="text" id = "validateCode" name="validateCode" class="form-control code" placeholder="验证码" maxlength="5"/>
</div>
<div class="col-xs-6">
<a href="javascript:void(0);" title="点击更换验证码">
<img th:src="@{/captcha/captchaImage(type=${'math'})}" class="imgcode"/>
</a>
</div>
</div>点击图片切换验证码js
$(function () {
$('.imgcode').click(function () {
var url = "/captcha/captchaImage?type=math&s=" + Math.random();
$(".imgcode").attr("src", url);
});
});1.CaptchaController
代码如下（示例）：
@Controller
@RequestMapping("/captcha")
public class CaptchaController {
@Resource(name = "captchaProducer")
private Producer captchaProducer;
@Resource(name = "captchaProducerMath")
private Producer captchaProducerMath;
/**
* 验证码生成
*/
@GetMapping(value = "/captchaImage")
public ModelAndView getKaptchaImage(HttpServletRequest request, HttpServletResponse response){
ServletOutputStream out = null;
try{
HttpSession session = request.getSession();
response.setDateHeader("Expires", 0);
response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
response.addHeader("Cache-Control", "post-check=0, pre-check=0");
response.setHeader("Pragma", "no-cache");
response.setContentType("image/jpeg");
String type = request.getParameter("type");
String capStr = null;
String code = null;
BufferedImage bi = null;
if ("math".equals(type))
{
//capText:"6/6=?@1"
String capText = captchaProducerMath.createText();
capStr = capText.substring(0, capText.lastIndexOf("@"));
code = capText.substring(capText.lastIndexOf("@") + 1);
bi = captchaProducerMath.createImage(capStr);
}
else if ("char".equals(type))
{
capStr = code = captchaProducer.createText();
bi = captchaProducer.createImage(capStr);
}
session.setAttribute(Constants.KAPTCHA_SESSION_KEY, code);
out = response.getOutputStream();
ImageIO.write(bi, "jpg", out);
out.flush();
} catch (IOException e) {
e.printStackTrace();
}finally
{
try
{
if (out != null)
{
out.close();
}
}
catch (IOException e)
{
e.printStackTrace();
}
}
return null;
}
}说明：调用captchaProducerMath.createText()方法生成的capText是形如“6/6=?@1”的字符串，使用ImageIO将@前面部分以jpg形式的图片输出，后部分存入session中以备登录时验证，也可整合redis使用，将验证部分存入redis中并设置过期时间。
2.CaptchaConfig
代码如下（示例）：
@Configuration
public class CaptchaConfig {
@Bean(name = "captchaProducer")
public DefaultKaptcha getKaptchaBean()
{
DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
Properties properties = new Properties();
// 是否有边框 默认为true 我们可以自己设置yes，no
properties.setProperty(KAPTCHA_BORDER, "yes");
// 验证码文本字符颜色 默认为Color.BLACK
properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_COLOR, "black");
// 验证码图片宽度 默认为200
properties.setProperty(KAPTCHA_IMAGE_WIDTH, "160");
// 验证码图片高度 默认为50
properties.setProperty(KAPTCHA_IMAGE_HEIGHT, "60");
// 验证码文本字符大小 默认为40
properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_SIZE, "38");
// KAPTCHA_SESSION_KEY
properties.setProperty(KAPTCHA_SESSION_CONFIG_KEY, "kaptchaCode");
// 验证码文本字符长度 默认为5
properties.setProperty(KAPTCHA_TEXTPRODUCER_CHAR_LENGTH, "4");
// 验证码文本字体样式 默认为new Font("Arial", 1, fontSize), new Font("Courier", 1, fontSize)
properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_NAMES, "Arial,Courier");
// 图片样式 水纹com.google.code.kaptcha.impl.WaterRipple 鱼眼com.google.code.kaptcha.impl.FishEyeGimpy 阴影com.google.code.kaptcha.impl.ShadowGimpy
properties.setProperty(KAPTCHA_OBSCURIFICATOR_IMPL, "com.google.code.kaptcha.impl.ShadowGimpy");
Config config = new Config(properties);
defaultKaptcha.setConfig(config);
return defaultKaptcha;
}
@Bean(name = "captchaProducerMath")
public DefaultKaptcha getKaptchaBeanMath()
{
DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
Properties properties = new Properties();
// 是否有边框 默认为true 我们可以自己设置yes，no
properties.setProperty(KAPTCHA_BORDER, "yes");
// 边框颜色 默认为Color.BLACK
properties.setProperty(KAPTCHA_BORDER_COLOR, "105,179,90");
// 验证码文本字符颜色 默认为Color.BLACK
properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_COLOR, "blue");
// 验证码图片宽度 默认为200
properties.setProperty(KAPTCHA_IMAGE_WIDTH, "160");
// 验证码图片高度 默认为50
properties.setProperty(KAPTCHA_IMAGE_HEIGHT, "50");
// 验证码文本字符大小 默认为40
properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_SIZE, "35");
// KAPTCHA_SESSION_KEY
properties.setProperty(KAPTCHA_SESSION_CONFIG_KEY, "kaptchaCodeMath");
// 验证码文本生成器
properties.setProperty(KAPTCHA_TEXTPRODUCER_IMPL, "com.tonglei.config.KaptchaTextCreator");
// 验证码文本字符间距 默认为2
properties.setProperty(KAPTCHA_TEXTPRODUCER_CHAR_SPACE, "3");
// 验证码文本字符长度 默认为5
properties.setProperty(KAPTCHA_TEXTPRODUCER_CHAR_LENGTH, "6");
// 验证码文本字体样式 默认为new Font("Arial", 1, fontSize), new Font("Courier", 1, fontSize)
properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_NAMES, "Arial,Courier");
// 验证码噪点颜色 默认为Color.BLACK
properties.setProperty(KAPTCHA_NOISE_COLOR, "white");
// 干扰实现类
properties.setProperty(KAPTCHA_NOISE_IMPL, "com.google.code.kaptcha.impl.NoNoise");
// 图片样式 水纹com.google.code.kaptcha.impl.WaterRipple 鱼眼com.google.code.kaptcha.impl.FishEyeGimpy 阴影com.google.code.kaptcha.impl.ShadowGimpy
properties.setProperty(KAPTCHA_OBSCURIFICATOR_IMPL, "com.google.code.kaptcha.impl.ShadowGimpy");
Config config = new Config(properties);
defaultKaptcha.setConfig(config);
return defaultKaptcha;
}
}3.KaptchaTextCreator
public class KaptchaTextCreator extends DefaultTextCreator
{
private static final String[] CNUMBERS = "0,1,2,3,4,5,6,7,8,9,10".split(",");
@Override
public String getText()
{
Integer result = 0;
Random random = new SecureRandom();
int x = random.nextInt(10);
int y = random.nextInt(10);
StringBuilder suChinese = new StringBuilder();
int randomoperands = (int) Math.round(Math.random() * 2);
if (randomoperands == 0)
{
result = x * y;
suChinese.append(CNUMBERS[x]);
suChinese.append("*");
suChinese.append(CNUMBERS[y]);
}
else if (randomoperands == 1)
{
if (!(x == 0) && y % x == 0)
{
result = y / x;
suChinese.append(CNUMBERS[y]);
suChinese.append("/");
suChinese.append(CNUMBERS[x]);
}
else
{
result = x + y;
suChinese.append(CNUMBERS[x]);
suChinese.append("+");
suChinese.append(CNUMBERS[y]);
}
}
else if (randomoperands == 2)
{
if (x >= y)
{
result = x - y;
suChinese.append(CNUMBERS[x]);
suChinese.append("-");
suChinese.append(CNUMBERS[y]);
}
else
{
result = y - x;
suChinese.append(CNUMBERS[y]);
suChinese.append("-");
suChinese.append(CNUMBERS[x]);
}
}
else
{
result = x + y;
suChinese.append(CNUMBERS[x]);
suChinese.append("+");
suChinese.append(CNUMBERS[y]);
}
suChinese.append("=?@" + result);
return suChinese.toString();
}
}4.LoginController
部分代码：
@PostMapping("/login")
@ResponseBody
public String loginMe(HttpSession session, String userName, String password, String validateCode) {
System.out.println("userName :" + userName + " , password :" + password + " , validateCode :" + validateCode);
Object attribute = session.getAttribute(Constants.KAPTCHA_SESSION_KEY);
String code = String.valueOf(attribute != null ? attribute : "");
if (StringUtils.isEmpty(attribute) || !validateCode.equalsIgnoreCase(code)) {
return ResMesUtil.build().resMesFail("验证码错误！");
}
UserEntity user = userService.findByUserNameAndPassword(userName, password);
if (user != null) {
session.setAttribute("userName", userName);
session.setAttribute("userType", user.getUserType());
return ResMesUtil.build().success();
}
return ResMesUtil.build().resMesFail("请输入正确的账号密码！");
}本文登录页验证码相关学习，源于开源项目若依，在此附上连接，多多支持开源项目。
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