java 生成验证码

1.引入maven依赖

     <dependency>
            <groupId>com.github.axet</groupId>
            <artifactId>kaptcha</artifactId>
            <version>0.0.9</version>
        </dependency>

2.配置属性

@Configuration
public class VerifyCodeConfig {
    @Bean
    public DefaultKaptcha producer() {
        Properties properties = new Properties();
        properties.put("kaptcha.border", "yes");//是否有边框
        properties.put("kaptcha.textproducer.font.color", "blue");//背景颜色
        properties.put("kaptcha.textproducer.char.space", "5");
        properties.put("kaptcha.textproducer.font.names", "Arial,Courier,cmr10,宋体,楷体,微软雅黑");//字体
        Config config = new Config(properties);
        DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
        defaultKaptcha.setConfig(config);
        return defaultKaptcha;
    }
}

3.创建一个contoller:

@Controller
public class ThymeleafController {
    @Autowired
    private Producer producer;
  
    @GetMapping("/get/verification/code")
    public void VerificationCode(HttpServletResponse response){
        response.setHeader("Cache-Control", "no-store, no-cache");
        response.setContentType("image/jpeg");
        String text = producer.createText(); //验证码内容可以保存数据库，并设置过期时间
        BufferedImage image = producer.createImage(text);
        ServletOutputStream out=null;
        try {
            out= response.getOutputStream();
            ImageIO.write(image, "jpg", out);
        }catch (Exception ex){
            if(null!=out){
                try {
                    out.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }
}

4.浏览器访问：