class Element implements Serializable, Cloneable {

    public final boolean isSerializable() {
        return isKeySerializable() && (value instanceof Serializable || value == null);
    }

    public  Element(Serializable key, Serializable value, long version);
    public  Element(Object key, Object value, long version);
    public  Element(Object key, Object value, long version,
                   long creationTime, long lastAccessTime,
                   long nextToLastAccessTime, long lastUpdateTime,
                   long hitCount);
    public  Element(Object key, Object value,
                   Boolean eternal, Integer timeToIdleSeconds, Integer timeToLiveSeconds);
    public  Element(Serializable key, Serializable value);
    public  Element(Object key, Object value);

}