3.3 添加工具类

@Component
public class ConstantPropertiesUtil implements InitializingBean {

    @Value("${wechat.mpAppId}")
    private String appid;

    @Value("${wechat.mpAppSecret}")
    private String appsecret;

    public static String ACCESS_KEY_ID;
    public static String ACCESS_KEY_SECRET;

    @Override
    public void afterPropertiesSet() throws Exception {
        ACCESS_KEY_ID = appid;
        ACCESS_KEY_SECRET = appsecret;
    }
}

@Configuration
public class WeChatMpConfig {

    @Autowired
    private ConstantPropertiesUtil constantPropertiesUtil;

    @Bean
    public WxMpService wxMpService(){
        WxMpService wxMpService = new WxMpServiceImpl();
        wxMpService.setWxMpConfigStorage(wxMpConfigStorage());
        return wxMpService;
    }

    @Bean
    public WxMpConfigStorage wxMpConfigStorage(){
        WxMpInMemoryConfigStorage wxMpConfigStorage = new WxMpInMemoryConfigStorage();
        wxMpConfigStorage.setAppId(ConstantPropertiesUtil.ACCESS_KEY_ID);
        wxMpConfigStorage.setSecret(ConstantPropertiesUtil.ACCESS_KEY_SECRET);
        return wxMpConfigStorage;
    }
}

3.4 Controller

@Slf4j
@Controller
@RequestMapping("/api/user/wechat")
public class WechatController {

    @Autowired
    private UserInfoService userInfoService;

    @Autowired
    private WxMpService wxMpService;

    //取出配置文件中的回调地址
    @Value("${wechat.userInfoUrl}")
    private String userInfoUrl;


    //授权跳转
    @GetMapping("authorize")
    public String authorize(@RequestParam("returnUrl") String returnUrl,
                            HttpServletRequest request) {
        String url = wxMpService.oauth2buildAuthorizationUrl(userInfoUrl,
                WxConsts.OAUTH2_SCOPE_USER_INFO,
                URLEncoder.encode(returnUrl.replace("guiguketan", "#")));
        return "redirect:"+url;
    }

    @GetMapping("userInfo")
    public String getUserInfoUrl(@RequestParam("code") String code,
                                 @RequestParam("state") String returnUrl){
        try {
            //拿着code请求
            WxMpOAuth2AccessToken wxMpOAuth2AccessToken = wxMpService.oauth2getAccessToken(code);
            //获取openid
            String openId = wxMpOAuth2AccessToken.getOpenId();
            log.info("openid:{}",openId);

            //获取微信信息
            WxMpUser wxMpUser = wxMpService.oauth2getUserInfo(wxMpOAuth2AccessToken, null);
            log.info("wxMpUser:{}", JSON.toJSONString(wxMpUser));

            //获取微信信息添加到数据库
            //先根据openid查询用户信息
            UserInfo userInfo=userInfoService.getUserInfoOpenid(openId);
            if(userInfo==null){ //数据库没有时添加到数据库中
                userInfo=new UserInfo();
                userInfo.setOpenId(openId);
                userInfo.setNickName(wxMpUser.getNickname());
                userInfo.setAvatar(wxMpUser.getHeadImgUrl());
                userInfo.setSex(wxMpUser.getSexId());
                userInfo.setProvince(wxMpUser.getProvince());

                userInfoService.save(userInfo);
            }
            //授权完成之后，跳转到具体的功能页面
            //生成token,按照一定规则生成字符串，可以包含用户信息
            String token= JwtHelper.createToken(userInfo.getId(),userInfo.getNickName());
            //localhost:8080/weixin?a=1&token=222
            if(returnUrl.indexOf("?")==-1){//若returnUrl中没有参数
                return "redirect:"+returnUrl+"?token="+token;
            }else{
                return "redirect:"+returnUrl+"&token="+token;
            }
        } catch (WxErrorException e) {
            e.printStackTrace();
        }
        return null;
    }
}

3.5 编写UserInfoService

@Service
public class UserInfoServiceImpl extends ServiceImpl<UserInfoMapper, UserInfo> implements UserInfoService {

    //根据openid擦寻用户信息
    @Override
    public UserInfo getUserInfoOpenid(String openId) {
        QueryWrapper<UserInfo> wrapper=new QueryWrapper<>();
        wrapper.eq("open_id",openId);
        UserInfo userInfo = baseMapper.selectOne(wrapper);
        return userInfo;
    }
}

3.6 使用token

  通过token传递用户信息

<dependencies>
	<dependency>
		<groupId>org.apache.httpcomponents</groupId>
		<artifactId>httpclient</artifactId>
	</dependency>
	<dependency>
		<groupId>io.jsonwebtoken</groupId>
		<artifactId>jjwt</artifactId>
	</dependency>
	<dependency>
		<groupId>joda-time</groupId>
		<artifactId>joda-time</artifactId>
	</dependency>
</dependencies>

public class JwtHelper {
    //token字符串有效时间
    private static long tokenExpiration = 24*60*60*1000;
    //加密编码秘钥
    private static String tokenSignKey = "123456";

    //根据userid  和  username 生成token字符串
    public static String createToken(Long userId, String userName) {
        String token = Jwts.builder()
                //设置token分类
                .setSubject("GGKT-USER")
                //token字符串有效时长
                .setExpiration(new Date(System.currentTimeMillis() + tokenExpiration))
                //私有部分（用户信息）
                .claim("userId", userId)
                .claim("userName", userName)
                //根据秘钥使用加密编码方式进行加密，对字符串压缩
                .signWith(SignatureAlgorithm.HS512, tokenSignKey)
                .compressWith(CompressionCodecs.GZIP)
                .compact();
        return token;
    }

    //从token字符串获取userid
    public static Long getUserId(String token) {
        if(StringUtils.isEmpty(token)) return null;
        Jws<Claims> claimsJws = Jwts.parser().setSigningKey(tokenSignKey).parseClaimsJws(token);
        Claims claims = claimsJws.getBody();
        Integer userId = (Integer)claims.get("userId");
        return userId.longValue();
    }

    //从token字符串获取getUserName
    public static String getUserName(String token) {
        if(StringUtils.isEmpty(token)) return "";
        Jws<Claims> claimsJws
                = Jwts.parser().setSigningKey(tokenSignKey).parseClaimsJws(token);
        Claims claims = claimsJws.getBody();
        return (String)claims.get("userName");
    }

    public static void main(String[] args) {
        String token = JwtHelper.createToken(1L, "lucy");
        System.out.println(token);
        System.out.println(JwtHelper.getUserId(token));
        System.out.println(JwtHelper.getUserName(token));
    }
}