XStream ler um XML

public static void main(String args[]) {
            
            // criando um Aluno
             Aluno aluno= new Aluno("Marcelo Andrade", 9912344L, new double[] {9.0, 8.5, 7.0, 10.0}, true );
             // exibindo o resultado da serialização com XStream
             XStream xstream= new XStream();
             xstream.alias("Aluno", Aluno.class);
             String representacao= xstream.toXML(aluno);
             
             System.out.println(representacao);
             File arquivo = new File("aluno.xml");
	     FileOutputStream gravar;
	        try {
	            gravar = new FileOutputStream(arquivo);
	            gravar.write(xstream.toXML(representacao).getBytes());
	            gravar.close();
	        } catch (IOException ex) {
	            ex.printStackTrace();
	        }
    }

private static void lerXML() throws FileNotFoundException {
        
        XmlSerializer xmlser = new XmlSerializer(new DomDriver());
        xmlser.deserialize("endereco.xml", Aluno.class);
        
        FileInputStream fis = new FileInputStream(new File("aluno.xml"));
        XStream xStream = new XStream(new DomDriver());
        Aluno a = (Aluno) xStream.fromXML(fis);
        System.out.println(a.getNomeCompleto());
}

public static void main(String[] args) {   
        try {        
            lerXML();
        } catch (FileNotFoundException ex) {
            Logger.getLogger(lerXML.class.getName()).log(Level.SEVERE, null, ex);
        }
            
        }