secure_programming_in_Java

//Sesion Manager //Gestión de Sesiones//

public class SessionManager {
    private static final int SESSION_TIMEOUT = 30 * 60; // 30 minutos
    private static final Map sessions = new ConcurrentHashMap<>();

    public static class Session {
        private final String id;
        private final String userId;
        private final Map attributes;
        private final long creationTime;
        private long lastAccessTime;

        public Session(String userId) {
            this.id = generateSessionId();
            this.userId = userId;
            this.attributes = new ConcurrentHashMap<>();
            this.creationTime = System.currentTimeMillis();
            this.lastAccessTime = this.creationTime;
        }

        private String generateSessionId() {
            return UUID.randomUUID().toString() + 
                   SecureRandomUtil.generateToken(32);
        }
    }

    public static Session createSession(String userId) {
        Session session = new Session(userId);
        sessions.put(session.id, session);
        return session;
    }

    public static void invalidateSession(String sessionId) {
        sessions.remove(sessionId);
    }

    public static boolean isValidSession(String sessionId) {
        Session session = sessions.get(sessionId);
        if (session == null) return false;

        long currentTime = System.currentTimeMillis();
        if (currentTime - session.lastAccessTime > SESSION_TIMEOUT * 1000) {
            invalidateSession(sessionId);
            return false;
        }

        session.lastAccessTime = currentTime;
        return true;
    }