public void persistir() {
		FileOutputStream fos = null;
		ObjectOutputStream stream = null;
		try {
			fos = new FileOutputStream("arquivo.bin");
			stream = new ObjectOutputStream(fos);
			stream.writeObject(persistencia);

		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (fos != null) {
				try {
					fos.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (stream != null) {
				try {
					stream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}