Program: 51828
Project: 51828
Buggy source:
private void prepareDataEntryPanel(JComponent panel,GridBagConstraints gbc){
  if (dataEntryPanel.getComponentCount() == 0) {
    if (!isEditable())     return;
    final JLabel prompt=new JLabel("String_Node_Str");
    final JTextArea textArea=new JTextArea();
    final JLabel updateButton=new JLabel("String_Node_Str");
    referenceArea=new ReferenceArea();
    referenceArea.setVisible(false);
    updateButton.setVisible(false);
    textArea.setBorder(BorderFactory.createLineBorder(Color.LIGHT_GRAY,1));
    textArea.setDropTarget(referenceArea.getDropTarget());
    prompt.setForeground(Color.GRAY);
    dataEntryPanel=new JPanel();
    dataEntryPanel.setOpaque(false);
    dataEntryPanel.add(prompt);
    MouseListener dataEntryMouseListener=new MouseListener(){
      boolean active=false;
      @Override public void mouseClicked(      MouseEvent arg0){
        if (arg0.getSource().equals(dataEntryPanel)) {
          if (active)           return;
          dataEntryPanel.removeAll();
          dataEntryPanel.add(textArea);
          dataEntryPanel.add(updateButton);
          referenceArea.setVisible(!referenceArea.getReferences().isEmpty());
          textArea.grabFocus();
          revalidate();
          repaint();
          active=true;
        }
 else         if (arg0.getSource().equals(updateButton)) {
          if (updateButton.isVisible() && active) {
            AbstractComponent comp=getManifestedComponent();
            if (comp instanceof UserLogComponent) {
              List<AbstractComponent> references=referenceArea.getReferences();
              ((UserLogComponent)comp).addEntry(textArea.getText(),references);
              PlatformAccess.getPlatform().getPersistenceProvider().startRelatedOperations();
              comp.save();
              PlatformAccess.getPlatform().getPersistenceProvider().completeRelatedOperations(true);
              textArea.setText("String_Node_Str");
              updateButton.setVisible(false);
              referenceArea.setVisible(false);
              referenceArea.clear();
              dataEntryPanel.removeAll();
              dataEntryPanel.add(prompt);
              revalidate();
              active=false;
              setupView();
            }
          }
        }
 else {
          if (!active)           return;
          dataEntryPanel.removeAll();
          dataEntryPanel.add(prompt);
          referenceArea.setVisible(false);
          revalidate();
          repaint();
          active=false;
        }
      }
      @Override public void mouseEntered(      MouseEvent arg0){
      }
      @Override public void mouseExited(      MouseEvent arg0){
      }
      @Override public void mousePressed(      MouseEvent arg0){
      }
      @Override public void mouseReleased(      MouseEvent arg0){
      }
    }
;
    textArea.addKeyListener(new KeyListener(){
      @Override public void keyPressed(      KeyEvent arg0){
      }
      @Override public void keyReleased(      KeyEvent arg0){
      }
      @Override public void keyTyped(      KeyEvent arg0){
        updateButton.setVisible(!textArea.getText().isEmpty());
      }
    }
);
    dataEntryPanel.addMouseListener(dataEntryMouseListener);
    updateButton.addMouseListener(dataEntryMouseListener);
    addMouseListener(dataEntryMouseListener);
  }
  gbc.gridx=1;
  gbc.weightx=1.0;
  panel.add(dataEntryPanel,gbc);
  gbc.gridx=2;
  gbc.weightx=1.0;
  gbc.fill=GridBagConstraints.HORIZONTAL;
  panel.add(referenceArea,gbc);
}

Fixed version (ground truth):
private void prepareDataEntryPanel(JComponent panel,GridBagConstraints gbc){
  if (dataEntryPanel.getComponentCount() == 0) {
    if (!isEditable())     return;
    final JLabel prompt=new JLabel("String_Node_Str");
    final JTextArea textArea=new JTextArea();
    final JLabel updateButton=new JLabel("String_Node_Str");
    referenceArea=new ReferenceArea();
    referenceArea.setVisible(false);
    updateButton.setVisible(false);
    textArea.setBorder(BorderFactory.createLineBorder(Color.LIGHT_GRAY,1));
    textArea.setDropTarget(referenceArea.getDropTarget());
    prompt.setForeground(Color.GRAY);
    dataEntryPanel=new JPanel();
    dataEntryPanel.setOpaque(false);
    dataEntryPanel.add(prompt);
    MouseListener dataEntryMouseListener=new MouseListener(){
      boolean active=false;
      @Override public void mouseClicked(      MouseEvent arg0){
        if (arg0.getSource().equals(dataEntryPanel)) {
          if (active)           return;
          dataEntryPanel.removeAll();
          dataEntryPanel.add(textArea);
          dataEntryPanel.add(updateButton);
          referenceArea.setVisible(!referenceArea.getReferences().isEmpty());
          textArea.grabFocus();
          revalidate();
          repaint();
          active=true;
        }
 else         if (arg0.getSource().equals(updateButton)) {
          if (updateButton.isVisible() && active) {
            AbstractComponent comp=getManifestedComponent();
            if (comp instanceof UserLogComponent) {
              List<AbstractComponent> references=referenceArea.getReferences();
              ((UserLogComponent)comp).addEntry(textArea.getText(),references);
              comp.save();
              textArea.setText("String_Node_Str");
              updateButton.setVisible(false);
              referenceArea.setVisible(false);
              referenceArea.clear();
              dataEntryPanel.removeAll();
              dataEntryPanel.add(prompt);
              revalidate();
              active=false;
              setupView();
            }
          }
        }
 else {
          if (!active)           return;
          dataEntryPanel.removeAll();
          dataEntryPanel.add(prompt);
          referenceArea.setVisible(false);
          revalidate();
          repaint();
          active=false;
        }
      }
      @Override public void mouseEntered(      MouseEvent arg0){
      }
      @Override public void mouseExited(      MouseEvent arg0){
      }
      @Override public void mousePressed(      MouseEvent arg0){
      }
      @Override public void mouseReleased(      MouseEvent arg0){
      }
    }
;
    textArea.addKeyListener(new KeyListener(){
      @Override public void keyPressed(      KeyEvent arg0){
      }
      @Override public void keyReleased(      KeyEvent arg0){
      }
      @Override public void keyTyped(      KeyEvent arg0){
        updateButton.setVisible(!textArea.getText().isEmpty());
      }
    }
);
    dataEntryPanel.addMouseListener(dataEntryMouseListener);
    updateButton.addMouseListener(dataEntryMouseListener);
    addMouseListener(dataEntryMouseListener);
  }
  gbc.gridx=1;
  gbc.weightx=1.0;
  panel.add(dataEntryPanel,gbc);
  gbc.gridx=2;
  gbc.weightx=1.0;
  gbc.fill=GridBagConstraints.HORIZONTAL;
  panel.add(referenceArea,gbc);
}