SpringBoot集成JWT生成token及校验方法过程解析

public class JwtTokenUtil {

  //公用密钥-保存在服务端,客户端是不会知道密钥的,以防被攻击
  public static String SECRET = "ThisIsASecret";

  //生成Troke
  public static String createToken(String username) {
    //签发时间
    //Date iatDate = new Date();
    //过地时间 1分钟后过期
    //Calendar nowTime = Calendar.getInstance();
    //nowTime.add(Calendar.MINUTE, 1);
    //Date expiresDate = nowTime.getTime();
    Map<String, Object> map = new HashMap();
    map.put("alg", "HS256");
    map.put("typ", "JWT");
    String token = JWT.create()
          .withHeader(map)
          //.withClaim( "name","Free码生") //设置 载荷 Payload
          //.withClaim("age","12")
          //.withClaim( "org","测试")
          //.withExpiresAt(expiresDate)//设置过期时间,过期时间要大于签发时间
          //.withIssuedAt(iatDate)//设置签发时间
          .withAudience(username) //设置 载荷 签名的观众
          .sign(Algorithm.HMAC256(SECRET));//加密
    System.out.println("后台生成token:" + token);
    return token;
  }

  //校验TOKEN
  public static boolean verifyToken(String token) throws UnsupportedEncodingException{
    JWTVerifier verifier = JWT.require(Algorithm.HMAC256(SECRET)).build();
    try {
      verifier.verify(token);
      return true;
    } catch (Exception e){
      return false;
    }
  }

  //获取Token信息
  public static DecodedJWT getTokenInfo(String token) throws UnsupportedEncodingException{
    JWTVerifier verifier = JWT.require(Algorithm.HMAC256(SECRET)).build();
    try{
      return verifier.verify(token);
    } catch(Exception e){
      throw new RuntimeException(e);
    }
  }

}

@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface UserLoginToken {
  boolean required() default true;
}

@Configuration
public class InterceptorConfig implements WebMvcConfigurer {
  @Override
  public void addInterceptors(InterceptorRegistry registry) {
    registry.addInterceptor(authenticationInterceptor())
        .addPathPatterns("/**");  // 拦截所有请求，通过判断是否有 @LoginRequired 注解 决定是否需要登录
  }
  @Bean
  public AuthenticationInterceptor authenticationInterceptor() {
    return new AuthenticationInterceptor();
  }
}

public class AuthenticationInterceptor implements HandlerInterceptor {
  @Autowired
  UserService userService;
  @Override
  public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) throws Exception {
    String token = httpServletRequest.getHeader("token");// 从 http 请求头中取出 token
    // 如果不是映射到方法直接通过
    if(!(object instanceof HandlerMethod)){
      return true;
    }
    HandlerMethod handlerMethod=(HandlerMethod)object;
    Method method=handlerMethod.getMethod();
    //检查是否有passtoken注释，有则跳过认证
    if (method.isAnnotationPresent(PassToken.class)) {
      PassToken passToken = method.getAnnotation(PassToken.class);
      if (passToken.required()) {
        return true;
      }
    }
    //检查有没有需要用户权限的注解
    if (method.isAnnotationPresent(UserLoginToken.class)) {
      UserLoginToken userLoginToken = method.getAnnotation(UserLoginToken.class);
      if (userLoginToken.required()) {
        // 执行认证
        if (token == null) {
          throw new RuntimeException("无token，请重新登录");
        }
        // 验证 token
        if(JwtTokenUtil.verifyToken(token)){
          return true;
        }else {
          throw new RuntimeException("401");
        }
      }
    }
    return true;
  }
  @Override
  public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
  }
  @Override
  public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
  }
}

@Controller
@RequestMapping(path = "/api")
public class IndexController {

  private String prefix = "index/";

  @GetMapping("/index")
  public String index()
  {
    return prefix + "index";
  }

  @UserLoginToken
  @PostMapping("/test")
  @ResponseBody
  public Object test(){
    Map<String,Object> map = new HashMap<>();
    map.put("code","200");
    map.put("message","你已通过验证了");
    return map;
  }
}