@Configuration
public class KcaptchaConfig {

	@Bean
	DefaultKaptcha defaultKaptcha() {
		Properties p = new Properties(11);
		p.setProperty(Constants.KAPTCHA_BORDER, "no");
		p.setProperty(Constants.KAPTCHA_IMAGE_WIDTH, "200");
		p.setProperty(Constants.KAPTCHA_IMAGE_HEIGHT, "40");
		p.setProperty(Constants.KAPTCHA_TEXTPRODUCER_CHAR_LENGTH, "6");
		p.setProperty(Constants.KAPTCHA_TEXTPRODUCER_FONT_NAMES, "宋体");
		p.setProperty(Constants.KAPTCHA_TEXTPRODUCER_FONT_SIZE, "38");
		p.setProperty(Constants.KAPTCHA_TEXTPRODUCER_CHAR_STRING, "2345678abcehmkx");
		p.setProperty(Constants.KAPTCHA_TEXTPRODUCER_CHAR_SPACE, "4");
		p.setProperty(Constants.KAPTCHA_TEXTPRODUCER_IMPL, "com.google.code.kaptcha.text.impl.TextProducer456");

		p.setProperty(Constants.KAPTCHA_BACKGROUND_CLR_FROM, "white");
		p.setProperty(Constants.KAPTCHA_BACKGROUND_CLR_TO, "white");

		DefaultKaptcha dk = new DefaultKaptcha();
		dk.setKaptchaConfig(new KaptchaConfig(p));
		return dk;
	}
}

	@Autowired
	private DefaultKaptcha captchaProducer;

	// 文本
	String captchaText = captchaProducer.createText();
	BufferedImage image = captchaProducer.createImage(captchaText);

	try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
		ImageIO.write(image, "png", out);
		String captchaImg = Base64.getEncoder().encodeToString(out.toByteArray());
		System.out.println(captchaImg);
	}

	// 算术
	ArithmeticTextProducer producer = new ArithmeticTextProducer();
	System.out.println(producer.getText());  // 输出如 "56 × 24 = ?"
	System.out.println("答案：" + producer.getAnswer()); // 输出对应计算结果