code: private void textFieldMaskKeyPressed(java.awt.event.KeyEvent evt) {//GEN-FIRST:event_textFieldMaskKeyPressed
      int selectedIndex = this.listFoundFiles.getSelectedIndex();
      boolean processed = false;
      if (!evt.isConsumed() && evt.getModifiers() == 0) {
        switch (evt.getKeyCode()) {
          case KeyEvent.VK_UP: {
            processed = true;
            evt.consume();
            if (selectedIndex >= 0) {
              selectedIndex--;
            }
          }
          break;
          case KeyEvent.VK_DOWN: {
            processed = true;
            evt.consume();
            if (selectedIndex >= 0) {
              selectedIndex++;
            }
          }
          break;
        }
  
        if (processed && !this.foundNodeList.isEmpty()) {
          if (selectedIndex < 0) {
            selectedIndex = this.foundNodeList.size() - 1;
          } else if (selectedIndex >= this.foundNodeList.size()) {
            selectedIndex = 0;
          }
          this.listFoundFiles.setSelectedIndex(selectedIndex);
          this.listFoundFiles.ensureIndexIsVisible(selectedIndex);
        }
  
      }
    }
docs: GEN-LAST:event_listFoundFilesMouseMoved