1. 添加依赖

<dependency>
    <groupId>com.auth0</groupId>
    <artifactId>java-jwt</artifactId>
    <version>3.8.2</version>
    <exclusions>
        <exclusion>
            <artifactId>commons-codec</artifactId>
            <groupId>commons-codec</groupId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>commons-codec</groupId>
    <artifactId>commons-codec</artifactId>
    <version>1.11</version>
</dependency>

2. 工具类

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTCreator;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.TokenExpiredException;
import com.auth0.jwt.interfaces.Claim;
import com.auth0.jwt.interfaces.DecodedJWT;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
/**
 * @author polaris <450733605@qq.com>
 * Description JWT Token工具类
 * Date 2020-12-28 17:53
 * Version 1.0.0
 */
public class JwtUtil {
    // 设置过期时间
    private static final long EXPIRE_DATE = 1 * 60 * 1000;
    // token秘钥（长度需要达到加密算法要求，过短会抛异常）
    private static final String TOKEN_SECRET = "1AsdadSAS123daXXsdafsadpolarisdf34234fdfsdfdsfdsafsd";
    // 密钥（服务重启后会随机生成，不推荐使用）
    private static final Algorithm algorithm = Algorithm.HMAC256(TOKEN_SECRET);
    /**
     * 生成token
     *
     * @param param 自定义参数或者覆盖jwt参数，默认有效期30分钟
     * @return
     */
    public static String token(Map<String, Object> param) {
        return token(param, null);
    }
    /**
     * 生成token（指定有效期）
     *
     * @param param
     * @param expireTimeMillis 有效期（毫秒数）
     * @return
     */
    public static String token(Map<String, Object> param, Long expireTimeMillis) {
        String token;
        Date expire = new Date(System.currentTimeMillis() + EXPIRE_DATE);
        if (expireTimeMillis != null && expireTimeMillis > 0) {
            expire = new Date(System.currentTimeMillis() + expireTimeMillis);
        }
        try {
            // 设置头部信息
            Map<String, Object> header = new HashMap<>();
            header.put("typ", "JWT");
            header.put("alg", "HS256");
            JWTCreator.Builder builder = JWT.create()
                    .withHeader(header);
            if (param != null && param.size() > 0) {
                param.forEach((k, v) -> {
                    builder.withClaim(k, String.valueOf(v));
                });
            }
            token = builder
                    .withExpiresAt(expire)
                    .sign(algorithm);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        return token;
    }
    /**
     * 验证Token有效性
     * @param token
     * @return
     */
    public static boolean verify(String token) {
        try {
            JWTVerifier verifier = JWT.require(algorithm).build();
            verifier.verify(token);
            return true;
        }catch (TokenExpiredException te){
            System.err.println(te.getMessage());
            return false;
        }catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }
    /**
     * 解析Token
     *
     * @param token
     * @return
     */
    public static Map<String, Object> parserToken(String token) {
        Map<String, Object> map = new HashMap<>();
        try {
            DecodedJWT t=JWT.require(algorithm).build().verify(token);
            Map<String, Claim> claims=t.getClaims();
            if(claims!=null && claims.size()>0){
                claims.forEach((k,v) -> {
                    if("exp".equalsIgnoreCase(k)){
                        map.put(k, v.asDate());
                    }else{
                        map.put(k, v.asString());
                    }
                });
            }
        }catch (TokenExpiredException te){
            System.err.println(te.getMessage());
            return null;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        return map;
    }
    public static void main(String[] args) {
        Map<String, Object> param = new HashMap<>();
        param.put("username", "sha san");
        param.put("password", "123");
        String token = token(param);
        System.out.println(String.format("token:{%s}",token));
        System.out.println("-----------------------------------------------------");
        //token="eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJwYXNzd29yZCI6IjEyMyIsImV4cCI6MTYwOTE1MjU2OCwidXNlcm5hbWUiOiJzaGEgc2FuIn0._eOF0ftDWuL0G2kBBXWn2sft5UwNhqxAaYHJmfvT0KA";
        if(verify(token)){
            System.out.println("验证成功！");
        }else{
            System.out.println("验证失败！");
        }
        Map<String, Object> resMap =parserToken(token);
        System.out.println("=====================================================");
        System.out.println(resMap);
    }
}