Program: 69053
Project: 69053
Buggy source:
public void widgetSelected(SelectionEvent e){
  Object source=e.getSource();
  if (source == fCmbAggregate) {
    String aggFunc=((String[])fCmbAggregate.getData())[fCmbAggregate.getSelectionIndex()];
    showAggregateParameters(aggFunc);
    if (AGG_FUNC_NONE.equals(aggFunc)) {
      fGrouping.setEnabled(false);
      fGrouping.setAggregateExpression(null);
    }
 else {
      fGrouping.setEnabled(true);
      fGrouping.setAggregateExpression(aggFunc);
    }
  }
 else   if (isAggParametersWidget(source)) {
    setAggParameter((Text)source);
  }
 else   if (isBuilderBtnWidget(source)) {
    try {
      Text txtArg=fExprBuilderWidgetsMap.get(source);
      String sExpr=fChartContext.getUIServiceProvider().invoke(IUIServiceProvider.COMMAND_EXPRESSION_DATA_BINDINGS,txtArg.getText(),fChartContext.getExtendedItem(),fTitle);
      txtArg.setText(sExpr);
      setAggParameter(txtArg);
    }
 catch (    ChartException e1) {
      WizardBase.displayException(e1);
    }
  }
 else   if (source == fBtnOK) {
    if (query != null) {
      query.setGrouping(fGrouping);
      query.getGrouping().eAdapters().addAll(query.eAdapters());
      fSeriesDefi.setGrouping(null);
    }
 else {
      fSeriesDefi.setGrouping(fGrouping);
      fSeriesDefi.getGrouping().eAdapters().addAll(fSeriesDefi.eAdapters());
    }
    ChartUIUtil.checkAggregateType(fChartContext);
    DataDefinitionTextManager.getInstance().updateTooltip();
    closeAggregateEditor(getShell());
  }
 else   if (source == fBtnCancel) {
    closeAggregateEditor(getShell());
  }
}

Fixed version (ground truth):
public void widgetSelected(SelectionEvent e){
  Object source=e.getSource();
  if (source == fCmbAggregate) {
    String aggFunc=((String[])fCmbAggregate.getData())[fCmbAggregate.getSelectionIndex()];
    showAggregateParameters(aggFunc);
    if (AGG_FUNC_NONE.equals(aggFunc)) {
      fGrouping.setEnabled(false);
      fGrouping.setAggregateExpression(null);
    }
 else {
      fGrouping.setEnabled(true);
      fGrouping.setAggregateExpression(aggFunc);
    }
  }
 else   if (isAggParametersWidget(source)) {
    setAggParameter((Text)source);
  }
 else   if (isBuilderBtnWidget(source)) {
    try {
      Text txtArg=fExprBuilderWidgetsMap.get(source);
      String sExpr=fChartContext.getUIServiceProvider().invoke(IUIServiceProvider.COMMAND_EXPRESSION_DATA_BINDINGS,txtArg.getText(),fChartContext.getExtendedItem(),fTitle);
      txtArg.setText(sExpr);
      setAggParameter(txtArg);
    }
 catch (    ChartException e1) {
      WizardBase.displayException(e1);
    }
  }
 else   if (source == fBtnOK) {
    if (query != null) {
      query.setGrouping(fGrouping);
      query.getGrouping().eAdapters().addAll(query.eAdapters());
      if (fSeriesDefi != null) {
        fSeriesDefi.setGrouping(null);
      }
    }
 else {
      fSeriesDefi.setGrouping(fGrouping);
      fSeriesDefi.getGrouping().eAdapters().addAll(fSeriesDefi.eAdapters());
    }
    ChartUIUtil.checkAggregateType(fChartContext);
    DataDefinitionTextManager.getInstance().updateTooltip();
    closeAggregateEditor(getShell());
  }
 else   if (source == fBtnCancel) {
    closeAggregateEditor(getShell());
  }
}