JWT工具类

创建JWT工具类

引入依赖

<!--jwt依赖-->
<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt</artifactId>
    <version>0.9.0</version>
</dependency>

创建 JwtUtil 工具类

package com.liu.goods.utils.jwt;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.JwtBuilder;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;

import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;
import java.util.Date;
import java.util.UUID;

/** * JWT工具类 */
public class JwtUtil {
    

    //有效期为
    public static final Long JWT_TTL = 60 * 60 *1000L;// 60 * 60 *1000 一个小时
    //设置秘钥明文
    public static final String JWT_KEY = "xiuhui";

    public static String getUUID(){
    
        String token = UUID.randomUUID().toString().replaceAll("-", "");
        return token;
    }
    
    /** * 生成jtw * @param subject token中要存放的数据（json格式） * @return */
    public static String createJWT(String subject) {
    
        JwtBuilder builder = getJwtBuilder(subject, null, getUUID());// 设置过期时间
        return builder.compact();
    }

    /** * 生成jtw * @param subject token中要存放的数据（json格式） * @param ttlMillis token超时时间 * @return */
    public static String createJWT(String subject, Long ttlMillis) {
    
        JwtBuilder builder = getJwtBuilder(subject, ttlMillis, getUUID());// 设置过期时间
        return builder.compact();
    }

    private static JwtBuilder getJwtBuilder(String subject, Long ttlMillis, String uuid) {
    
        SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;
        SecretKey secretKey = generalKey();
        long nowMillis = System.currentTimeMillis();
        Date now = new Date(nowMillis);
        if(ttlMillis==null){
    
            ttlMillis=JwtUtil.JWT_TTL;
        }
        long expMillis = nowMillis + ttlMillis;
        Date expDate = new Date(expMillis);
        return Jwts.builder()
                .setId(uuid)              //唯一的ID
                .setSubject(subject)   // 主题 可以是JSON数据
                .setIssuer("sg")     // 签发者
                .setIssuedAt(now)      // 签发时间
                .signWith(signatureAlgorithm, secretKey) //使用HS256对称加密算法签名, 第二个参数为秘钥
                .setExpiration(expDate);
    }

    /** * 创建token * @param id * @param subject * @param ttlMillis * @return */
    public static String createJWT(String id, String subject, Long ttlMillis) {
    
        JwtBuilder builder = getJwtBuilder(subject, ttlMillis, id);// 设置过期时间
        return builder.compact();
    }

    public static void main(String[] args) throws Exception {
    
        String token = "eyJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJjYWM2ZDVhZi1mNjVlLTQ0MDAtYjcxMi0zYWEwOGIyOTIwYjQiLCJzdWIiOiJzZyIsImlzcyI6InNnIiwiaWF0IjoxNjM4MTA2NzEyLCJleHAiOjE2MzgxMTAzMTJ9.JVsSbkP94wuczb4QryQbAke3ysBDIL5ou8fWsbt_ebg";
        Claims claims = parseJWT(token);
        System.out.println(claims);
    }

    /** * 生成加密后的秘钥 secretKey * @return */
    public static SecretKey generalKey() {
    
        byte[] encodedKey = Base64.getDecoder().decode(JwtUtil.JWT_KEY);
        SecretKey key = new SecretKeySpec(encodedKey, 0, encodedKey.length, "AES");
        return key;
    }
    
    /** * 解析 * * @param jwt * @return * @throws Exception */
    public static Claims parseJWT(String jwt) throws Exception {
    
        SecretKey secretKey = generalKey();
        return Jwts.parser()
                .setSigningKey(secretKey)
                .parseClaimsJws(jwt)
                .getBody();
    }

}

使用

创建,以token返回前端

String adminId = loginUser.getAdmin().getId().toString();
String jwt= JwtUtil.createJWT(adminId);

Map<String,Object> map=new HashMap<>();
map.put("securityToken",jwt);
return map;

解析，查看是否过期

//解析token
String adminId =null;
try {
    
    Claims claims = JwtUtil.parseJWT(token);
    adminId = claims.getSubject();
} catch (Exception e) {
    
    e.printStackTrace();
    throw  new RuntimeException("token非法");
}