token续时的问题

[yangfan321p]

public class CreateJWT {
	
	private static final String SECRET = "XX#$%()(#*!()!KL<><MQLMNQNQJQK sdfkjsdrow32234545fdf>?N<:{LWPW";

    private static final String EXP = "exp";

    private static final String PAYLOAD = "payload";

//加密封装了用户信息的实体类
    public static <T> String sign(T object, long maxAge) {
        try {
            final JWTSigner signer = new JWTSigner(SECRET);
            final Map<String, Object> claims = new HashMap<String, Object>();
            ObjectMapper mapper = new ObjectMapper();
            String jsonString = mapper.writeValueAsString(object);
            claims.put(PAYLOAD, jsonString);
            claims.put(EXP, System.currentTimeMillis()+maxAge);
            System.out.println("时长为=="+maxAge);
            return signer.sign(claims);
        } catch(Exception e) {
            return null;
        }
    }

  //解密token返回实体类
    public static<T> T unsign(String jwt, Class<T> classT) {
        final JWTVerifier verifier = new JWTVerifier(SECRET);
        try {
            final Map<String,Object> claims= verifier.verify(jwt);
            if (claims.containsKey(EXP) && claims.containsKey(PAYLOAD)) {
                long exp = (Long)claims.get(EXP);
                long currentTimeMillis = System.currentTimeMillis();
                if (exp > currentTimeMillis) {
                    String json = (String)claims.get(PAYLOAD);
                    ObjectMapper objectMapper = new ObjectMapper();
                    return objectMapper.readValue(json, classT);
                }
            }
            return null;
        } catch (Exception e) {
            return null;
        }
    }
}

只有一个加密和解密的方法，请问用户每次请求应该给他重新续时吧，我设置是半小时，那怎么改
之前项目维护人写的是把这个加密的token存在了redis中，那我拦截器拦截了用户带着token的请求，解密后和redis中的token解密比对后通过，如果没有过期，我该怎么延长token时间？

[Cathy313]

if (exp > currentTimeMillis) 时，修改你的map中的EXP的值，比如map.put(EXP, System.currentTimeMillis()+maxAge)覆盖掉原来的时间信息