Springboot如何生成图片验证码并验证？

1.添加依赖

    <dependency>
        <groupId>com.github.penggle</groupId>
        <artifactId>kaptcha</artifactId>
        <version>2.3.2</version>
    </dependency>
    
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

项目结构

全部代码

UserController

package com.yzm.config;

import java.util.HashMap;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

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

import com.google.code.kaptcha.impl.DefaultKaptcha;
import com.yzm.utils.Util;

@Controller
public class TestControler {

  @Resource
  private DefaultKaptcha captchaProducer;
  /**
   * 登录验证码SessionKey
   */
  public static final String LOGIN_VALIDATE_CODE = "login_validate_code";
  /**
   * 登录验证码图片
   */
  @RequestMapping(value = {"/loginValidateCode"})
  public void loginValidateCode(HttpServletRequest request, HttpServletResponse response) throws Exception{
      Util.validateCode(request,response,captchaProducer,LOGIN_VALIDATE_CODE);
  }

  /**
   * 检查验证码是否正确
   */
  @RequestMapping("/checkLoginValidateCode")
  @ResponseBody
  public HashMap checkLoginValidateCode(HttpServletRequest request,@RequestParam("validateCode")String validateCode) {
      String loginValidateCode = request.getSession().getAttribute(LOGIN_VALIDATE_CODE).toString();
      HashMap<String,Object> map = new HashMap<String,Object>();
      if(loginValidateCode == null){
          map.put("status",null);//验证码过期
      }else if(loginValidateCode.equals(validateCode)){
          map.put("status",true);//验证码正确
      }else if(!loginValidateCode.equals(validateCode)){
          map.put("status",false);//验证码不正确
      }
      map.put("code",200);
      return map;
  }
}

package com.yzm.controller;

import java.util.Properties;

import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;

import com.google.code.kaptcha.impl.DefaultKaptcha;
import com.google.code.kaptcha.util.Config;

@Component
public class TestConfig {
 
    @Bean
    public DefaultKaptcha getDefaultKaptcha() {
        DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
        Properties properties = new Properties();
        // 图片边框
        properties.setProperty("kaptcha.border", "no");
        // 边框颜色
        properties.setProperty("kaptcha.border.color", "black");
        //边框厚度
        properties.setProperty("kaptcha.border.thickness", "1");
        // 图片宽
        properties.setProperty("kaptcha.image.width", "200");
        // 图片高
        properties.setProperty("kaptcha.image.height", "50");
        //图片实现类
        properties.setProperty("kaptcha.producer.impl", "com.google.code.kaptcha.impl.DefaultKaptcha");
        //文本实现类
        properties.setProperty("kaptcha.textproducer.impl", "com.google.code.kaptcha.text.impl.DefaultTextCreator");
        //文本集合，验证码值从此集合中获取
        properties.setProperty("kaptcha.textproducer.char.string", "01234567890");
        //验证码长度
        properties.setProperty("kaptcha.textproducer.char.length", "4");
        //字体
        properties.setProperty("kaptcha.textproducer.font.names", "宋体");
        //字体颜色
        properties.setProperty("kaptcha.textproducer.font.color", "black");
        //文字间隔
        properties.setProperty("kaptcha.textproducer.char.space", "5");
        //干扰实现类
        properties.setProperty("kaptcha.noise.impl", "com.google.code.kaptcha.impl.DefaultNoise");
        //干扰颜色
        properties.setProperty("kaptcha.noise.color", "blue");
        //干扰图片样式
        properties.setProperty("kaptcha.obscurificator.impl", "com.google.code.kaptcha.impl.WaterRipple");
        //背景实现类
        properties.setProperty("kaptcha.background.impl", "com.google.code.kaptcha.impl.DefaultBackground");
        //背景颜色渐变，结束颜色
        properties.setProperty("kaptcha.background.clear.to", "white");
        //文字渲染器
        properties.setProperty("kaptcha.word.impl", "com.google.code.kaptcha.text.impl.DefaultWordRenderer");
        Config config = new Config(properties);
        defaultKaptcha.setConfig(config);
        return defaultKaptcha;
    }
 
}

Util

package com.yzm.utils;

import java.awt.image.BufferedImage;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.google.code.kaptcha.impl.DefaultKaptcha;

public class Util {
     
    /**
     * 生成验证码图片
     * @param request 设置session
     * @param response 转成图片
     * @param captchaProducer 生成图片方法类
     * @param validateSessionKey session名称
     * @throws Exception
     */
    public static void validateCode(HttpServletRequest request, HttpServletResponse response, DefaultKaptcha captchaProducer, String validateSessionKey) throws Exception{
        // Set to expire far in the past.
        response.setDateHeader("Expires", 0);
        // Set standard HTTP/1.1 no-cache headers.
        response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
        // Set IE extended HTTP/1.1 no-cache headers (use addHeader).
        response.addHeader("Cache-Control", "post-check=0, pre-check=0");
        // Set standard HTTP/1.0 no-cache header.
        response.setHeader("Pragma", "no-cache");
 
        // return a jpeg
        response.setContentType("image/jpeg");
 
        // create the text for the image
        String capText = captchaProducer.createText();
 
        // store the text in the session
        request.getSession().setAttribute(validateSessionKey, capText);
 
        // create the image with the text
        BufferedImage bi = captchaProducer.createImage(capText);
 
        ServletOutputStream out = response.getOutputStream();
 
        // write the data out
        ImageIO.write(bi, "jpg", out);
        try {
            out.flush();
        } finally {
            out.close();
        }
    }
}