private void baseFileButtonActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_baseFileButtonActionPerformed
        if (evt.getSource() == baseFileButton) {
            final JFileChooser fc = new JFileChooser();
            int returnVal = fc.showOpenDialog(this);
            
            if (returnVal == JFileChooser.APPROVE_OPTION) {
                File chosenFile = fc.getSelectedFile();
                if (!chosenFile.exists()) {
                    JOptionPane.showMessageDialog(this, "File does not exist!");
                }
                if (!chosenFile.canRead()) {
                    JOptionPane.showMessageDialog(this, "Cannot read file.");
                }
                baseFile = chosenFile;
                baseFileButton.setText(baseFile.getName());
            }
        }
    }//GEN-LAST:event_baseFileButtonActionPerformed