Program: 140620
Project: 140620
Buggy source:
public void setElements(final ColumnIndicator[] elements){
  this.tree.dispose();
  this.tree=createTree(this.parentComp);
  tree.setData(VIEWER_KEY,this);
  this.columnIndicators=elements;
  for (int i=0; i < elements.length; i++) {
    final TreeItem treeItem=new TreeItem(tree,SWT.NONE);
    final ColumnIndicator columnIndicator=(ColumnIndicator)elements[i];
    treeItem.setImage(ImageLib.getImage(ImageLib.TD_COLUMN));
    String columnName=columnIndicator.getTdColumn().getName();
    treeItem.setText(0,columnName != null ? columnName + PluginConstant.SPACE_STRING + PluginConstant.PARENTHESIS_LEFT+ columnIndicator.getTdColumn().getSqlDataType().getName()+ PluginConstant.PARENTHESIS_RIGHT : "String_Node_Str");
    treeItem.setData(COLUMN_INDICATOR_KEY,columnIndicator);
    TreeEditor comboEditor=new TreeEditor(tree);
    final CCombo combo=new CCombo(tree,SWT.BORDER);
    for (    DataminingType type : DataminingType.values()) {
      combo.add(type.getLiteral());
    }
    DataminingType dataminingType=MetadataHelper.getDataminingType(columnIndicator.getTdColumn());
    if (dataminingType == null) {
      dataminingType=MetadataHelper.getDefaultDataminingType(columnIndicator.getTdColumn().getJavaType());
    }
    if (dataminingType == null) {
      combo.select(0);
    }
 else {
      combo.setText(dataminingType.getLiteral());
    }
    combo.addSelectionListener(new SelectionAdapter(){
      public void widgetSelected(      SelectionEvent e){
        MetadataHelper.setDataminingType(DataminingType.get(combo.getText()),columnIndicator.getTdColumn());
        setDirty(true);
      }
    }
);
    combo.setEditable(false);
    comboEditor.minimumWidth=WIDTH1_CELL;
    comboEditor.setEditor(combo,treeItem,1);
    TreeEditor addPatternEditor=new TreeEditor(tree);
    Button addPatternBtn=new Button(tree,SWT.NONE);
    addPatternBtn.setText("String_Node_Str");
    addPatternBtn.pack();
    addPatternBtn.addSelectionListener(new SelectionAdapter(){
      @Override public void widgetSelected(      SelectionEvent e){
        CheckedTreeSelectionDialog dialog=new CheckedTreeSelectionDialog(null,new PatternLabelProvider(),new WorkbenchContentProvider());
        IFolder defaultPatternFolder=ResourcesPlugin.getWorkspace().getRoot().getProject(DQStructureManager.LIBRARIES).getFolder(DQStructureManager.PATTERNS);
        dialog.setInput(defaultPatternFolder);
        dialog.setContainerMode(true);
        dialog.setTitle("String_Node_Str");
        dialog.setMessage("String_Node_Str");
        dialog.setSize(80,30);
        dialog.create();
        if (dialog.open() == Window.OK) {
          for (          Object obj : dialog.getResult()) {
            if (obj instanceof IFile) {
              IFile file=(IFile)obj;
              Pattern pattern=PatternResourceFileHelper.getInstance().findPattern(file);
              PatternMatchingIndicator patternMatchingIndicator=PatternIndicatorFactory.createRegexpMatchingIndicator(pattern);
              DependenciesHandler.getInstance().setDependencyOn(patternMatchingIndicator,pattern);
              IndicatorEnum type=IndicatorEnum.findIndicatorEnum(patternMatchingIndicator.eClass());
              IndicatorUnit addIndicatorUnit=columnIndicator.addSpecialIndicator(type,patternMatchingIndicator);
              createOneUnit(treeItem,addIndicatorUnit);
              setDirty(true);
            }
          }
        }
      }
    }
);
    addPatternEditor.minimumWidth=WIDTH1_CELL;
    addPatternEditor.setEditor(addPatternBtn,treeItem,2);
    TreeEditor delLabelEditor=new TreeEditor(tree);
    Label delLabel=new Label(tree,SWT.NONE);
    delLabel.setBackground(Display.getDefault().getSystemColor(SWT.COLOR_WHITE));
    delLabel.setImage(ImageLib.getImage(ImageLib.DELETE_ACTION));
    delLabel.setToolTipText("String_Node_Str");
    delLabel.pack();
    delLabel.addMouseListener(new MouseAdapter(){
      @Override public void mouseDown(      MouseEvent e){
        deleteColumnItems(columnIndicator);
        if (treeItem.getParentItem() != null && treeItem.getParentItem().getData(INDICATOR_UNIT_KEY) != null) {
          setElements(columnIndicators);
        }
 else {
          removeItemBranch(treeItem);
        }
      }
    }
);
    delLabelEditor.minimumWidth=WIDTH1_CELL;
    delLabelEditor.horizontalAlignment=SWT.CENTER;
    delLabelEditor.setEditor(delLabel,treeItem,3);
    treeItem.setData(ITEM_EDITOR_KEY,new TreeEditor[]{comboEditor,delLabelEditor,addPatternEditor});
    if (columnIndicator.hasIndicators()) {
      createIndicatorItems(treeItem,columnIndicator.getIndicatorUnits());
    }
    treeItem.setExpanded(true);
  }
  this.setDirty(true);
}

Fixed version (ground truth):
public void setElements(final ColumnIndicator[] elements){
  this.tree.dispose();
  this.tree=createTree(this.parentComp);
  tree.setData(VIEWER_KEY,this);
  this.columnIndicators=elements;
  addItemElements(elements);
}