public boolean hasChanged() {
			if (!file.exists()) {
				if (exists) {
					exists = false;
					return true;
				}
				return false;
			}
			if (!exists) {
				exists = true;
				this.timestamp = file.lastModified();
				return true;
			}
			long current = file.lastModified();
			if (current != timestamp) {
				timestamp = current;
				return true;
			}
			return false;
		}