使用Java生成JWT(JSON Web Token)的方法示例

<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt</artifactId>
    <version>0.9.1</version>
</dependency>

import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import java.util.Date;

public class JwtUtils {

    private static final String SECRET_KEY = "your_secret_key";

    public static String generateJwt(String subject, long expirationMillis) {
        Date now = new Date();
        Date expirationDate = new Date(now.getTime() + expirationMillis);

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

public class Main {

    public static void main(String[] args) {
        String jwt = JwtUtils.generateJwt("user123", 3600000); // 有效期为1小时
        System.out.println("Generated JWT: " + jwt);
    }
}