java验证码接口

1.maven依赖

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

2.配置

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;

@Component
public class KaptchaConfig {
    @Bean
    public DefaultKaptcha getDefaultKaptcha() {
        DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
        Properties properties = new Properties();
        // 图片边框
        properties.setProperty("kaptcha.border", "yes");
        // 边框颜色
        properties.setProperty("kaptcha.border.color", "105,179,90");
        // 字体颜色
        properties.setProperty("kaptcha.textproducer.font.color", "red");
        // 图片宽
        properties.setProperty("kaptcha.image.width", "130");
        // 图片高
        properties.setProperty("kaptcha.image.height", "40");
        // 字体大小
        properties.setProperty("kaptcha.textproducer.font.size", "30");
        // session key
        properties.setProperty("kaptcha.session.key", "code");
        // 验证码长度
        properties.setProperty("kaptcha.textproducer.char.length", "4");
        // 文字间距
        properties.put("kaptcha.textproducer.char.space", "7");
        // 字体
        properties.put("kaptcha.textproducer.font.names", "Arial,cmr10");
        // 采用那些文字
        properties.put("kaptcha.textproducer.char.string", "ABCDEFGHJKLMNPQRSTUVWXYZ13456789abcdeghjknsuvwxyz");
        Config config = new Config(properties);
        defaultKaptcha.setConfig(config);

        return defaultKaptcha;
    }
}

3.接口

@Controller
@RequestMapping("kaptcha")
@Slf4j
@Api(tags = {"验证码生成接口"})
public class KaptchaController {

    /**
     * 1、验证码工具
     */
    @Autowired
    DefaultKaptcha defaultKaptcha;

    /**
     * 生成验证码
     * @param request
     * @param response
     * @throws Exception
     */
    @ApiOperation(value = "生成验证码")
    @GetMapping("generateKaptcha")
    public void defaultKaptcha(HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        byte[] captchaChallengeAsJpeg = null;
        ByteArrayOutputStream jpegOutputStream = null;
        ServletOutputStream responseOutputStream = null;
        try {
            jpegOutputStream = new ByteArrayOutputStream();
            // 生产验证码字符串并保存到session中
            String createText = defaultKaptcha.createText();
            log.info("sessionId={},验证码={}", request.getSession().getId(), createText);
            request.getSession().setAttribute(Constant.VERIFY_CODE, createText);
            // 使用生产的验证码字符串返回一个BufferedImage对象并转为byte写入到byte数组中
            BufferedImage challenge = defaultKaptcha.createImage(createText);
            ImageIO.write(challenge, "jpg", jpegOutputStream);
            // 定义response输出类型为image/jpeg类型，使用response输出流输出图片的byte数组
            captchaChallengeAsJpeg = jpegOutputStream.toByteArray();
            response.setHeader("Cache-Control", "no-store");
            response.setHeader("Pragma", "no-cache");
            response.setDateHeader("Expires", 0);
            response.setContentType("image/jpeg");
            responseOutputStream = response.getOutputStream();
            responseOutputStream.write(captchaChallengeAsJpeg);
        } catch (IllegalArgumentException e) {
            response.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        } finally {
            IOUtils.closeQuietly(jpegOutputStream);
            IOUtils.closeQuietly(responseOutputStream);
        }
    }
}