Java.lang.OutOfMemoryError: GC overhead limit exceeded

public class Main {

    public static void main(String[] args) {
        XStream xstream = new XStream();
        List valores = new ArrayList();
        BufferedReader br = null;
        try {
            String fileName = "arquivo4.txt";
            br = new BufferedReader(new FileReader(fileName));
            SequenceIterator stream = SeqIOTools.readFastaDNA(br);
            while(stream.hasNext()){
                try {
                    org.biojava.bio.seq.Sequence seq = stream.nextSequence();
                    //valores.add(seq);
                    DNA dna = new DNA();
                    dna.setNome(seq.getName());
                    dna.setSequencia(seq.seqString());
                    dna.setQualidade(seq.seqString());
                    valores.add(dna);
                    //System.out.println("Nome: " + seq.getName() + "\tURN: " + seq.seqString());
                } catch (NoSuchElementException ex) {
                    Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
                } catch (BioException ex) {
                    Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
                }
            }


        } catch (FileNotFoundException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            try {
                br.close();
            } catch (IOException ex) {
                Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
            }
        }

        String contatosEmXML = xstream.toXML(valores);
        System.out.println("\nContatos em XML:");
        System.out.println(contatosEmXML);
        
    }
}