Program: 66190
Project: 66190
Buggy source:
public void handleEvent(Event event){
  if (event.widget.equals(wliacLine)) {
    boolean isUnset=(event.detail == ChartElementUtil.PROPERTY_UNSET);
    if (event.type == LineAttributesComposite.VISIBILITY_CHANGED_EVENT) {
      ChartElementUtil.setEObjectAttribute(series.getWebLineAttributes(),"String_Node_Str",((Boolean)event.data).booleanValue(),isUnset);
    }
 else     if (event.type == LineAttributesComposite.STYLE_CHANGED_EVENT) {
      ChartElementUtil.setEObjectAttribute(series.getWebLineAttributes(),"String_Node_Str",(LineStyle)event.data,isUnset);
    }
 else     if (event.type == LineAttributesComposite.WIDTH_CHANGED_EVENT) {
      ChartElementUtil.setEObjectAttribute(series.getWebLineAttributes(),"String_Node_Str",((Integer)event.data).intValue(),isUnset);
    }
 else     if (event.type == LineAttributesComposite.COLOR_CHANGED_EVENT) {
      series.getWebLineAttributes().setColor((ColorDefinition)event.data);
    }
  }
 else   if (event.widget.equals(webMin)) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmin > tmax)     tmin=tmax;
    series.setWebLabelMin(tmin);
    webMin.setText(Double.toString(tmin));
  }
 else   if (event.widget.equals(webMax)) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmax < tmin)     tmax=tmin;
    series.setWebLabelMax(tmax);
    webMax.setText(Double.toString(tmax));
  }
 else   if (event.widget.equals(btnTranslucentBullseye)) {
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",btnTranslucentBullseye.getSelectionState() == TristateCheckbox.STATE_SELECTED,btnTranslucentBullseye.getSelectionState() == TristateCheckbox.STATE_GRAYED);
  }
 else   if (event.widget.equals(iscScaleCnt)) {
    series.setPlotSteps(BigInteger.valueOf(iscScaleCnt.getSelection()));
  }
 else   if (event.widget.equals(btnAutoScale)) {
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",btnAutoScale.getSelectionState() == TristateCheckbox.STATE_SELECTED,btnAutoScale.getSelectionState() == TristateCheckbox.STATE_GRAYED);
    boolean enabled=btnAutoScale.getSelectionState() == TristateCheckbox.STATE_SELECTED;
    updateScaleUI(enabled);
  }
 else   if (event.widget == btnScaleCntAuto) {
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",BigInteger.valueOf(iscScaleCnt.getSelection()),btnScaleCntAuto.getSelection());
    iscScaleCnt.setEnabled(btnAutoScale.getSelectionState() != TristateCheckbox.STATE_GRAYED && !btnScaleCntAuto.getSelection());
  }
 else   if (event.widget == btnWebMinAuto) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmin > tmax)     tmin=tmax;
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",tmin,btnWebMinAuto.getSelection());
    webMin.setEnabled(!btnWebMinAuto.getSelection());
  }
 else   if (event.widget == btnWebMaxAuto) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmax < tmin)     tmax=tmin;
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",tmax,btnWebMaxAuto.getSelection());
    webMax.setEnabled(!btnWebMaxAuto.getSelection());
  }
}

Fixed version (ground truth):
public void handleEvent(Event event){
  if (event.widget.equals(wliacLine)) {
    boolean isUnset=(event.detail == ChartElementUtil.PROPERTY_UNSET);
    if (event.type == LineAttributesComposite.VISIBILITY_CHANGED_EVENT) {
      ChartElementUtil.setEObjectAttribute(series.getWebLineAttributes(),"String_Node_Str",((Boolean)event.data).booleanValue(),isUnset);
    }
 else     if (event.type == LineAttributesComposite.STYLE_CHANGED_EVENT) {
      ChartElementUtil.setEObjectAttribute(series.getWebLineAttributes(),"String_Node_Str",event.data,isUnset);
    }
 else     if (event.type == LineAttributesComposite.WIDTH_CHANGED_EVENT) {
      ChartElementUtil.setEObjectAttribute(series.getWebLineAttributes(),"String_Node_Str",((Integer)event.data).intValue(),isUnset);
    }
 else     if (event.type == LineAttributesComposite.COLOR_CHANGED_EVENT) {
      series.getWebLineAttributes().setColor((ColorDefinition)event.data);
    }
  }
 else   if (event.widget.equals(webMin)) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmin > tmax)     tmin=tmax;
    series.setWebLabelMin(tmin);
    webMin.setText(Double.toString(tmin));
  }
 else   if (event.widget.equals(webMax)) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmax < tmin)     tmax=tmin;
    series.setWebLabelMax(tmax);
    webMax.setText(Double.toString(tmax));
  }
 else   if (event.widget.equals(btnTranslucentBullseye)) {
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",btnTranslucentBullseye.getSelectionState() == TristateCheckbox.STATE_SELECTED,btnTranslucentBullseye.getSelectionState() == TristateCheckbox.STATE_GRAYED);
  }
 else   if (event.widget.equals(iscScaleCnt)) {
    series.setPlotSteps(BigInteger.valueOf(iscScaleCnt.getSelection()));
  }
 else   if (event.widget.equals(btnAutoScale)) {
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",btnAutoScale.getSelectionState() == TristateCheckbox.STATE_SELECTED,btnAutoScale.getSelectionState() == TristateCheckbox.STATE_GRAYED);
    boolean enabled=ChartUIExtensionUtil.canEnableUI(btnAutoScale);
    updateScaleUI(enabled);
  }
 else   if (event.widget == btnScaleCntAuto) {
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",BigInteger.valueOf(iscScaleCnt.getSelection()),btnScaleCntAuto.getSelection());
    iscScaleCnt.setEnabled(ChartUIExtensionUtil.canEnableUI(btnAutoScale) && !btnScaleCntAuto.getSelection());
  }
 else   if (event.widget == btnWebMinAuto) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmin > tmax)     tmin=tmax;
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",tmin,btnWebMinAuto.getSelection());
    webMin.setEnabled(!btnWebMinAuto.getSelection());
  }
 else   if (event.widget == btnWebMaxAuto) {
    double tmin=this.getTypedDataElement(webMin.getText());
    double tmax=this.getTypedDataElement(webMax.getText());
    if (tmax < tmin)     tmax=tmin;
    ChartElementUtil.setEObjectAttribute(series,"String_Node_Str",tmax,btnWebMaxAuto.getSelection());
    webMax.setEnabled(!btnWebMaxAuto.getSelection());
  }
}