public void recuperar() {
		FileInputStream fis = null;
		ObjectInputStream stream = null;
		try {
			File arquivo = new File("arquivo.bin");
			if (arquivo.exists()) {
				fis = new FileInputStream(arquivo);
				stream = new ObjectInputStream(fis);
				persistencia = (Persistencia) stream.readObject();
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			if (fis != null) {
				try {
					fis.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (stream != null) {
				try {
					stream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}