Ref.: FTP zerado

private void btnBaixaArquivoActionPerformed(java.awt.event.ActionEvent evt) {
    org.apache.commons.net.ftp.FTPClient ftp = null;
    FileOutputStream fos = null;
    
    try {
        ftp = new org.apache.commons.net.ftp.FTPClient();
        fos = new FileOutputStream("pa.zip");
        
        ftp.connect("sigmine.dnpm.gov.br");
//        ftp.login("", "");
        
        ftp.retrieveFile("\pa_new.zip", fos);
        
    } catch (SocketException ex) {
        Logger.getLogger(AutorizacaoPesquisa.class.getName()).log(Level.SEVERE, null, ex);
    } catch (IOException ex) {
        Logger.getLogger(AutorizacaoPesquisa.class.getName()).log(Level.SEVERE, null, ex);
    } finally {
        if (fos != null) {
            try {
                fos.close();
                ftp.disconnect();
            } catch (IOException ex) {
                Logger.getLogger(AutorizacaoPesquisa.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }
}