使用JWT中的springboot实现一个权限验证功能

 <dependency>
      <groupId>com.auth0</groupId>
      <artifactId>java-jwt</artifactId>
      <version>3.8.1</version>
    </dependency>
    <dependency>
      <groupId>io.jsonwebtoken</groupId>
      <artifactId>jjwt</artifactId>
      <version>0.9.1</version>
    </dependency>

package com.qf.tyleryue_one.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * 自定义注解：方法前 表示方法需要拦截
 */
@Target({ElementType.METHOD,ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface JwtToken {
}

package com.qf.tyleryue_one.utils;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTCreator;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import jdk.internal.org.objectweb.asm.TypeReference;

import java.util.Date;

/**
 * 用来生成签名，校验签名，通过签名
 */
public class JwtUtils {
  //令牌有效时间
  private final static long EXPIRE_TIME=5*60*1000;
  //密钥
  private final static String SECRECT="Tyler_Yue_key";
  /**
   * 创建令牌
   */
  public static String sign(String userId){
    //构建失效时钟
    Date exipre_date = new Date(System.currentTimeMillis() + EXPIRE_TIME);
    //创建令牌
    JWTCreator.Builder builder = JWT.create();
    //给jwt令牌playload中放入发令牌放的用户
    //给userid用户发令牌
    builder.withAudience(userId);
    //设置令牌失效时间
    builder.withExpiresAt(exipre_date);
    //对令牌密钥进行加密
    Algorithm algorithm = Algorithm.HMAC256(SECRECT);
    String sign = builder.sign(algorithm);
    return sign;//返回令牌
  }
  /**
   * 验证令牌
   */
  public static boolean verifyToken(String token){

    try {
      //生成校验器
      Algorithm algorithm = Algorithm.HMAC256(SECRECT);
      //校验
      JWTVerifier build = JWT.require(algorithm).build();
      //无异常则校验成功
      return true;
    } catch (Exception e) {
      throw new RuntimeException("令牌过期");
    }
   
  }
}

package com.qf.tyleryue_one.vo;

import com.alibaba.druid.filter.AutoLoad;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

/**
 * 封装一个返回 含令牌的用户对象
 */
@Data
@AllArgsConstructor
@NoArgsConstructor
public class TokenVo {
  //用户名
  private String usernaem;
  //令牌名
  private String token;
}

package com.qf.tyleryue_one.controller;

import com.qf.tyleryue_one.entity.VueUser;
import com.qf.tyleryue_one.service.VueUserService;
import com.qf.tyleryue_one.utils.JwtUtils;
import com.qf.tyleryue_one.vo.Msg;
import com.qf.tyleryue_one.vo.TokenVo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;

import java.util.UUID;

/**
 * 登录业务
 */
@Controller
public class VueUserController {
  @Autowired
  private VueUserService vueUserService;

  @RequestMapping(value = "/dealLogin",method = RequestMethod.POST)
  @CrossOrigin
  @ResponseBody
  public Msg login(@RequestBody VueUser vueUser){
    VueUser vueUser1 = vueUserService.selectByUsername(vueUser.getUsername());

    if (vueUser1!=null){
      if (vueUser1.getPassword().equals(vueUser.getPassword())){
        //密码匹配，发放令牌
        ///随机生成字符串未userid
        String userid = UUID.randomUUID().toString();
        String token = JwtUtils.sign(userid);
        //封装令牌对象
        TokenVo tokenVo = new TokenVo(vueUser.getUsername(), token);
        return new Msg(200,"登录成功,令牌已发放",tokenVo);

      }else {
        return new Msg(403,"密码错误",null);
      }
    }else {
      return new Msg(403,"用户不存在",null);
    }
  }
}