jwt授权认证示例

**jwt：json+web+token

    com.auth0
    java-jwt
    3.4.0

请求头+有效载荷+签名**

public class JwtEmp {
    public static void main(String[] args) throws InterruptedException {
        //签名
        Algorithm java2202 = Algorithm.HMAC256("java2202");

        long currentTimeMillis = System.currentTimeMillis()+3000;

        Map hashMap = new HashMap();
        hashMap.put("k1","v1");
        String token = JWT.create()
                //请求头
                .withHeader(hashMap)
                //有效载荷
                .withClaim("name", "admin")
                .withClaim("age", 22)
                .withClaim("sal", 3000)
                //设置过期时间
                .withExpiresAt(new Date(currentTimeMillis))

                .sign(java2202);

        System.out.println("token数据："+token);
        Thread.sleep(4000);

        DecodedJWT verify = JWT.require(java2202).build().verify(token);

        //验证成功后获取token的数据
        String name = verify.getClaim("name").asString();
        Integer age = verify.getClaim("age").asInt();
        String header = verify.getHeader();
        Claim k1 = verify.getHeaderClaim("k1");
        System.out.println("值为"+k1.asString());
        System.out.println(name);
        System.out.println(age);
        System.out.println(header);

    }
}