实现验证码验证

导入依赖

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

代码实现

@Controller
public class VerificationCodeController {
    
    @Resource
    private DefaultKaptcha defaultKaptcha;
    @GetMapping("/common/kaptcha")
    public void defaultKaptch(HttpServletRequest httpServletRequest,HttpServletResponse httpServletResponse) throws IOException {
    
        byte[] captchaOutPutStream = null;
        // 数组字节输出流
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        try {
    
            //将生成的验证码保存到session中
            String kaptchaText = defaultKaptcha.createText();
            httpServletRequest.getSession().setAttribute("verifyCode",kaptchaText);
            BufferedImage image = defaultKaptcha.createImage(kaptchaText);
            ImageIO.write(image,"jpg",byteArrayOutputStream);
        } catch (IOException e) {
    
            httpServletResponse.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        }
        captchaOutPutStream = byteArrayOutputStream.toByteArray();
        httpServletResponse.setHeader("Cache-Control", "no-store");
        httpServletResponse.setHeader("Pragma", "no-cache");
        httpServletResponse.setDateHeader("Expires", 0);
        httpServletResponse.setContentType("image/jpeg");
        ServletOutputStream responseOutputStream = httpServletResponse.getOutputStream();
        responseOutputStream.write(captchaOutPutStream);
        responseOutputStream.flush();
        responseOutputStream.close();
    }
}

---

package com.cheng.controller.common;

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 sun.security.krb5.KrbException;

import java.util.Properties;

@Component
public class KaptchaConfig {
    
    @Bean
    public DefaultKaptcha getDefaultKaptcha() {
    
        com.google.code.kaptcha.impl.DefaultKaptcha defaultKaptcha = new com.google.code.kaptcha.impl.DefaultKaptcha();
        Properties properties = new Properties();
        properties.put("kaptcha.border","no");
        properties.put("kaptcha.textproducer.font.color", "black");
        properties.put("kaptcha.image.width", "150");
        properties.put("kaptcha.image.height", "40");
        properties.put("kaptcha.textproducer.font.size", "30");
        properties.put("kaptcha.session.key", "verifyCode");
        properties.put("kaptcha.textproducer.char.space", "5");
        Config config = new Config(properties);
        defaultKaptcha.setConfig(config);

        return defaultKaptcha;
    }
}

效果图