public Vector<File> searchFolder(String folderName) {
		File folderTmp = new File(folderName);
		Pattern regExp = Pattern.compile(".*\\.txt$");
		boolean encontrado = false;
		
		if (folderTmp.exists() && folderTmp.isDirectory()) {			
			for (String file : folderTmp.list()) {
				if (regExp.matcher(file).matches()) {
					fileVector.add(new File(folderName + "/" + file.toString()));
					encontrado = true;
				}
			}
			if (!encontrado) {
				System.out.println(" Ningún archivo .txt");
			}
		} else {
			System.out.println(" --- + ERROR. La carpeta indicada no existe " +
					"o no es un directorio.");
			System.out.println(" --- +++++++ Clase: PCorpus Fucion: public "
					+ "Vector<File> buscarCarpeta (String nombreCarpeta)");
		}
		return fileVector;
	}