code: private void buttonImportSettingsActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_buttonImportSettingsActionPerformed
      final File file = DialogProviderManager.getInstance().getDialogProvider().msgOpenFileDialog(null, "importSettings", "Import settings", lastImportedSettingsFile, true, new PropertiesFileFilter(), "Open");
      if (file != null) {
        lastImportedSettingsFile = file;
        try {
          final Preferences prefs = (new PropertiesPreferences("NB MindMap plugin", FileUtils.readFileToString(file, "UTF-8")));
          loadFromPreferences(prefs, this.config);
          this.controller.changed();
        } catch (final Exception ex) {
          LOGGER.error("Can't import settings", ex);
          DialogProviderManager.getInstance().getDialogProvider().msgError(null, "Can't import settings [" + ex.getMessage() + ']');
        }
      }
    }
docs: GEN-LAST:event_buttonExportSettingsActionPerformed