Program: 168154
Project: 168154
Buggy source:
@Override public void createContents(Composite parent){
  GridLayoutFactory.fillDefaults().numColumns(1).equalWidth(false).applyTo(parent);
  FormToolkit toolkit=mform.getToolkit();
  Section section=toolkit.createSection(parent,Section.DESCRIPTION | Section.TITLE_BAR | Section.EXPANDED);
  GridDataFactory.fillDefaults().grab(true,false).span(1,1).applyTo(section);
  GridLayoutFactory.fillDefaults().numColumns(3).applyTo(section);
  section.setText("String_Node_Str");
  section.setDescription("String_Node_Str");
  ScrolledComposite sc=new ScrolledComposite(section,SWT.H_SCROLL | SWT.V_SCROLL);
  sc.setExpandHorizontal(true);
  sc.setExpandVertical(true);
  GridLayoutFactory.fillDefaults().numColumns(3).equalWidth(false).applyTo(sc);
  Composite sectionClient=toolkit.createComposite(section);
  sc.setContent(sectionClient);
  GridDataFactory.fillDefaults().grab(true,false).applyTo(sc);
  GridLayoutFactory.fillDefaults().numColumns(3).equalWidth(false).applyTo(sectionClient);
  section.setClient(sectionClient);
  TacitFormComposite.createEmptyRow(toolkit,sectionClient);
  final Label classLbl=toolkit.createLabel(sectionClient,"String_Node_Str",SWT.NONE);
  GridDataFactory.fillDefaults().grab(false,false).span(1,0).applyTo(classLbl);
  classNameTxt=toolkit.createText(sectionClient,"String_Node_Str",SWT.BORDER);
  GridDataFactory.fillDefaults().grab(true,false).span(2,0).applyTo(classNameTxt);
  if (null != selectedCorpusClass) {
    classNameTxt.setText(selectedCorpusClass.getClassName());
  }
  classNameTxt.addKeyListener(new KeyListener(){
    @Override public void keyReleased(    KeyEvent e){
      if (isClassnameValid(classNameTxt.getText()))       selectedCorpusClass.setClassName(classNameTxt.getText());
      if (!selectedCorpusClass.getClassName().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
    @Override public void keyPressed(    KeyEvent e){
      if (isClassnameValid(classNameTxt.getText()))       selectedCorpusClass.setClassName(classNameTxt.getText());
      if (!selectedCorpusClass.getClassName().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
  }
);
  final Label classPathLbl=toolkit.createLabel(sectionClient,"String_Node_Str",SWT.NONE);
  GridDataFactory.fillDefaults().grab(false,false).span(1,0).applyTo(classPathLbl);
  classPathTxt=toolkit.createText(sectionClient,"String_Node_Str",SWT.BORDER);
  if (null != selectedCorpusClass)   classPathTxt.setText(selectedCorpusClass.getClassPath());
  GridDataFactory.fillDefaults().grab(true,false).span(1,0).applyTo(classPathTxt);
  final Button browseBtn=toolkit.createButton(sectionClient,"String_Node_Str",SWT.PUSH);
  browseBtn.addSelectionListener(new SelectionListener(){
    @Override public void widgetSelected(    SelectionEvent e){
      DirectoryDialog dlg=new DirectoryDialog(browseBtn.getShell(),SWT.OPEN);
      dlg.setText("String_Node_Str");
      String path=dlg.open();
      if (path == null)       return;
      classPathTxt.setText(path);
      selectedCorpusClass.setClassPath(classPathTxt.getText());
    }
    @Override public void widgetDefaultSelected(    SelectionEvent e){
    }
  }
);
  classPathTxt.addKeyListener(new KeyListener(){
    @Override public void keyReleased(    KeyEvent e){
      if (isClassPathValid(classPathTxt.getText()))       selectedCorpusClass.setClassPath(classPathTxt.getText());
      if (!selectedCorpusClass.getClassPath().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
    @Override public void keyPressed(    KeyEvent e){
      if (isClassPathValid(classPathTxt.getText()))       selectedCorpusClass.setClassPath(classPathTxt.getText());
      if (!selectedCorpusClass.getClassPath().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
  }
);
}

Fixed version (ground truth):
@Override public void createContents(Composite parent){
  GridLayoutFactory.fillDefaults().numColumns(1).equalWidth(false).applyTo(parent);
  FormToolkit toolkit=mform.getToolkit();
  Section section=toolkit.createSection(parent,Section.DESCRIPTION | Section.TITLE_BAR | Section.EXPANDED);
  GridDataFactory.fillDefaults().grab(true,false).span(1,1).applyTo(section);
  GridLayoutFactory.fillDefaults().numColumns(3).applyTo(section);
  section.setText("String_Node_Str");
  section.setDescription("String_Node_Str");
  ScrolledComposite sc=new ScrolledComposite(section,SWT.H_SCROLL | SWT.V_SCROLL);
  sc.setExpandHorizontal(true);
  sc.setExpandVertical(true);
  GridLayoutFactory.fillDefaults().numColumns(3).equalWidth(false).applyTo(sc);
  Composite sectionClient=toolkit.createComposite(section);
  sc.setContent(sectionClient);
  GridDataFactory.fillDefaults().grab(true,false).applyTo(sc);
  GridLayoutFactory.fillDefaults().numColumns(3).equalWidth(false).applyTo(sectionClient);
  section.setClient(sectionClient);
  TacitFormComposite.createEmptyRow(toolkit,sectionClient);
  final Label classLbl=toolkit.createLabel(sectionClient,"String_Node_Str",SWT.NONE);
  GridDataFactory.fillDefaults().grab(false,false).span(1,0).applyTo(classLbl);
  classNameTxt=toolkit.createText(sectionClient,"String_Node_Str",SWT.BORDER);
  GridDataFactory.fillDefaults().grab(true,false).span(2,0).applyTo(classNameTxt);
  if (null != selectedCorpusClass) {
    classNameTxt.setText(selectedCorpusClass.getClassName());
  }
  classNameTxt.addKeyListener(new KeyListener(){
    @Override public void keyReleased(    KeyEvent e){
      if (isClassnameValid(classNameTxt.getText())) {
        selectedCorpusClass.setClassName(classNameTxt.getText());
        selectedCorpusClass.getViewer().refresh();
      }
      if (!selectedCorpusClass.getClassName().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
    @Override public void keyPressed(    KeyEvent e){
      if (isClassnameValid(classNameTxt.getText())) {
        selectedCorpusClass.setClassName(classNameTxt.getText());
        selectedCorpusClass.getViewer().refresh();
      }
      if (!selectedCorpusClass.getClassName().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
  }
);
  final Label classPathLbl=toolkit.createLabel(sectionClient,"String_Node_Str",SWT.NONE);
  GridDataFactory.fillDefaults().grab(false,false).span(1,0).applyTo(classPathLbl);
  classPathTxt=toolkit.createText(sectionClient,"String_Node_Str",SWT.BORDER);
  if (null != selectedCorpusClass)   classPathTxt.setText(selectedCorpusClass.getClassPath());
  GridDataFactory.fillDefaults().grab(true,false).span(1,0).applyTo(classPathTxt);
  final Button browseBtn=toolkit.createButton(sectionClient,"String_Node_Str",SWT.PUSH);
  browseBtn.addSelectionListener(new SelectionListener(){
    @Override public void widgetSelected(    SelectionEvent e){
      DirectoryDialog dlg=new DirectoryDialog(browseBtn.getShell(),SWT.OPEN);
      dlg.setText("String_Node_Str");
      String path=dlg.open();
      if (path == null)       return;
      classPathTxt.setText(path);
      selectedCorpusClass.setClassPath(classPathTxt.getText());
    }
    @Override public void widgetDefaultSelected(    SelectionEvent e){
    }
  }
);
  classPathTxt.addKeyListener(new KeyListener(){
    @Override public void keyReleased(    KeyEvent e){
      if (isClassPathValid(classPathTxt.getText()))       selectedCorpusClass.setClassPath(classPathTxt.getText());
      if (!selectedCorpusClass.getClassPath().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
    @Override public void keyPressed(    KeyEvent e){
      if (isClassPathValid(classPathTxt.getText()))       selectedCorpusClass.setClassPath(classPathTxt.getText());
      if (!selectedCorpusClass.getClassPath().isEmpty())       corpusMgmtViewform.getMessageManager().removeMessage("String_Node_Str");
    }
  }
);
}