easy-captcha

easy-captcha是生成图形验证码的Java类库，支持gif、中文、算术等类型，可用于Java Web、JavaSE等项目。参考地址：https://gitee.com/whvse/EasyCaptcha

maven坐标：

    com.github.whvcse
    easy-captcha
    1.6.2

效果展示：

使用方式：

import com.wf.captcha.ArithmeticCaptcha;
import com.wf.captcha.ChineseCaptcha;
import com.wf.captcha.base.Captcha;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;

public class CaptchaTest {
    public static void main(String[] args) throws FileNotFoundException {
        //中文验证码
        Captcha captcha = new ChineseCaptcha();
        //获取本次生成的验证码
        String text = captcha.text();
        System.out.println(text);

        //输出验证码图片到d盘
        captcha.out(new FileOutputStream(new File("d:\\test.png")));

        //算术验证码
        Captcha captcha1 = new ArithmeticCaptcha();
        //获取本次生成的验证码
        String text1 = captcha1.text();
        System.out.println(text1);

        //输出验证码图片到d盘
        captcha1.out(new FileOutputStream(new File("d:\\test1.png")));
    }
}

开发验证码接口

1，创建LoginController并提供生成验证码的方法

import com.itheima.pinda.authority.biz.service.auth.ValidateCodeService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 登录
 * 配置文件pd-auth-server.yml中，"权限模块"扫描的包com.itheima.pinda.authority.controller.auth
 * 所以在swagger中可以在"权限模块"中查看
 */
@RestController
@RequestMapping("/anno")
@Api(value = "UserAuthController", tags = "登录控制器")
@Slf4j
public class LoginController {

    @Autowired
    private ValidateCodeService validateCodeService;

	/**
     * 生成验证码
     */
    @ApiOperation(value = "验证码", notes = "验证码")
    @GetMapping(value = "/captcha", produces = "image/png")
    public void captcha(@RequestParam(value = "key") String key,
                        HttpServletResponse response) throws IOException {
        validateCodeService.create(key, response);
    }

	 /**
     * 校验验证码
     */
    @ApiOperation(value = "校验验证码", notes = "校验验证码")
    @PostMapping(value = "/check")
    public boolean check(@RequestBody LoginParamDTO login)
            throws BizException {
        //校验验证码是否正确
        boolean check = validateCodeService.check(login.getKey(), login.getCode());
        return check;
    }
}

2，创建ValidateCodeService接口

import java.io.IOException;
import javax.servlet.http.HttpServletResponse;
/**
 * 验证码
 */
public interface ValidateCodeService {
    /**
     * 生成验证码
     */
    void create(String key, HttpServletResponse response) throws IOException;

	/**
     * 校验验证码
     * @param key   前端上送 key
     * @param value 前端上送待校验值
     */
    boolean check(String key, String value);
}

3，创建ValidateCodeServiceImpl

import com.itheima.pinda.authority.biz.service.auth.ValidateCodeService;
import com.itheima.pinda.common.constant.CacheKey;
import com.itheima.pinda.exception.BizException;
import com.wf.captcha.ArithmeticCaptcha;
import com.wf.captcha.base.Captcha;
import net.oschina.j2cache.CacheChannel;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Service;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 验证码服务
 */
@Service
public class ValidateCodeServiceImpl implements ValidateCodeService {
    @Autowired
    //通过当前对象可以操作j2cache缓存
    private CacheChannel cache;
    @Override
    //生成算术验证码，同时将验证码进行缓存
    public void create(String key, HttpServletResponse response) throws IOException {

        if (StringUtils.isBlank(key)) {
            throw BizException.validFail("验证码key不能为空");
        }

        Captcha captcha = new ArithmeticCaptcha(115, 42);
        captcha.setCharType(2);
        //本次产生的验证码
        String text = captcha.text();
        //将验证码进行缓存
        cache.set(CacheKey.CAPTCHA,key,text);

        response.setContentType(MediaType.IMAGE_PNG_VALUE);
        response.setHeader(HttpHeaders.PRAGMA, "No-cache");
        response.setHeader(HttpHeaders.CACHE_CONTROL, "No-cache");
        response.setDateHeader(HttpHeaders.EXPIRES, 0L);
		//将生成的验证码图片通过输出流写回客户端浏览器页面
        captcha.out(response.getOutputStream());
    }

	@Override
	//value前端需要验证的验证码
	//key,生成验证时,前端传过来的,存到缓存中的key
    public boolean check(String key, String value) {
        if (StringUtils.isBlank(value)) {
            throw BizException.validFail("请输入验证码");
        }
        //从指定区域CacheKey.CAPTCHA获取缓存key
        CacheObject cacheObject = cache.get(CacheKey.CAPTCHA, key);
        if (cacheObject.getValue() == null) {
            throw BizException.validFail("验证码已过期");
        }
        if (!StringUtils.equalsIgnoreCase(value, String.valueOf(cacheObject.getValue()))) {
            throw BizException.validFail("验证码不正确");
        }
        //验证通过，立即从缓存中删除验证码
        cache.evict(CacheKey.CAPTCHA, key);
        return true;
    }
}

4，验证码接口开发完成后可以启动服务，通过接口文档进行测试：

可以看到已经将验证码缓存到redis：