Springboot整合kaptcha验证码

pom.xml

<dependency>
    <groupId>com.github.penggle</groupId>
    <artifactId>kaptcha</artifactId>
    <version>2.3.2</version>
</dependency>

KaptchaConfig.java

import com.google.code.kaptcha.impl.DefaultKaptcha;
import com.google.code.kaptcha.util.Config;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;

import java.util.Properties;

/**
 * @Description: Kaptcha配置类
 */
@Component
public class KaptchaConfig {
    @Bean
    public DefaultKaptcha getDefaultKaptcha(){
        DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
        Properties properties = new Properties();
        // 是否使用边框
        properties.setProperty("kaptcha.border", "no");
        // 边框颜色
        properties.setProperty("kaptcha.border.color", "105,179,90");
        // 验证码字体颜色
        properties.setProperty("kaptcha.textproducer.font.color", "red");
        // 验证码图片的宽度
        properties.setProperty("kaptcha.image.width", "110");
        // 验证码图片的高度
        properties.setProperty("kaptcha.image.height", "40");
        // 验证码字体的大小
        properties.setProperty("kaptcha.textproducer.font.size", "40");
        // 验证码保存在session的key
        properties.setProperty("kaptcha.session.key", "code");
        // 验证码输出的字符长度
        properties.setProperty("kaptcha.textproducer.char.length", "4");
        // 验证码的字体设置
        properties.setProperty("kaptcha.textproducer.font.names", "宋体,楷体,微软雅黑");
        Config config = new Config(properties);
        defaultKaptcha.setConfig(config);
        return defaultKaptcha;
    }
}

CodeController.java

import com.google.code.kaptcha.Constants;
import com.google.code.kaptcha.Producer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

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.image.BufferedImage;

/**
 * @Description: 生成验证码接口
 */
@Controller
public class CodeController {
    @Autowired
    private Producer captchaProducer = null;

    @RequestMapping("/kaptcha")
    public void getKaptchaImage(HttpServletRequest request, HttpServletResponse response) throws Exception {
        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");
        //生成验证码
        String capText = captchaProducer.createText();
        session.setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);
        //向客户端写出
        BufferedImage bi = captchaProducer.createImage(capText);
        ServletOutputStream out = response.getOutputStream();
        ImageIO.write(bi, "jpg", out);
        try {
            out.flush();
        } finally {
            out.close();
        }
    }
}

VerifyCode.java

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;

/**
 * @Description: 验证码校验接口
 */
@RestController
public class VerifyCode {
    @RequestMapping("/verifyCode")
    public String verifyCode(HttpServletRequest request) {
        if (!CodeUtil.checkVerifyCode(request)) {
            return "验证码有误！";
        } else {
            return "hello,Kaptcha";
        }
    }
}

CodeUtil.java

import javax.servlet.http.HttpServletRequest;

/**
 * @Description: 验证码校验工具类
 */
public class CodeUtil {
    /**
     * 将获取到的前端参数转为string类型
     * @param request
     * @param key
     * @return
     */
    public static String getString(HttpServletRequest request, String key) {
        try {
            String result = request.getParameter(key);
            if(result != null) {
                result = result.trim();
            }
            if("".equals(result)) {
                result = null;
            }
            return result;
        }catch(Exception e) {
            return null;
        }
    }
    /**
     * 验证码校验
     * @param request
     * @return
     */
    public static boolean checkVerifyCode(HttpServletRequest request) {
        //获取生成的验证码
        String verifyCodeExpected = (String) request.getSession().getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
        //获取用户输入的验证码
        String verifyCodeActual = CodeUtil.getString(request, "verifyCodeKey");
        if(verifyCodeActual == null ||!verifyCodeActual.equals(verifyCodeExpected)) {
            return false;
        }
        return true;
    }
}

index.java

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * @Description: 跳转到index页面，index.html在 /resources/templates/ 目录下
 */
@Controller
public class index {
    @RequestMapping("/index")
    public String index() {
        return "index";
    }
}

index.html

<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script type="text/javascript">
        function refresh() {
            document.getElementById('captcha_img').src="/kaptcha?"+Math.random();
        }
    </script>
</head>
<body>
<form action="/verifyCode" method="post">
    验证码:  <input type="text" placeholder="请输入验证码" name="verifyCodeKey">
    <div class="item-input">
        <img id="captcha_img" alt="点击更换" title="点击更换"
             onclick="refresh()" src="/kaptcha" />
    </div>
    <input type="submit" value="提交" />
</form>
</body>
</html>

访问路径:

http://localhost:8080/index