java jwt token生成和验证代码

可以直接回答，以下是示例代码：

生成JWT Token：

import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;

import java.util.Date;

public class JwtUtil {
    private static final long EXPIRE_TIME = 5 * 60 * 1000;
    private static final String SECRET_KEY = "your-secret-key";

    public static String generateToken(String username) {
        Date now = new Date();
        Date expireTime = new Date(now.getTime() + EXPIRE_TIME);

        return Jwts.builder()
                .setSubject(username)
                .setIssuedAt(now)
                .setExpiration(expireTime)
                .signWith(SignatureAlgorithm.HS256, SECRET_KEY)
                .compact();
    }
}

验证JWT Token：

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;

public class JwtUtil {
    private static final String SECRET_KEY = "your-secret-key";

    public static String getUsernameFromToken(String token) {
        Claims claims = Jwts.parser()
                .setSigningKey(SECRET_KEY)
                .parseClaimsJws(token)
                .getBody();

        return claims.getSubject();
    }

    public static boolean validateToken(String token) {
        try {
            Jwts.parser().setSigningKey(SECRET_KEY).parseClaimsJws(token);
            return true;
        } catch (Exception e) {
            return false;
        }
    }
}