if (grouping.getGroupType() != null && grouping.getGroupType().equals("Date/Time")
if (bEnableUI && grouping.getGroupType() != null && grouping.getGroupType().equals("Date/Time")
    private void populateLists()    {        SeriesGrouping grouping = getGrouping();        boolean bEnableUI = btnEnabled.getSelection();        // Populate grouping type combo        cmbType.add("Text"); //$NON-NLS-1$        cmbType.add("Number"); //$NON-NLS-1$        cmbType.add("Date/Time"); //$NON-NLS-1$        if (grouping.getGroupType() != null)        {            cmbType.setText(getGrouping().getGroupType());        }        else        {            cmbType.select(0);        }        this.lblType.setEnabled(bEnableUI);        this.cmbType.setEnabled(bEnableUI);        this.lblInterval.setEnabled(bEnableUI);        this.iscInterval.setEnabled(bEnableUI);        // Populate grouping unit combo (applicable only if type is Date/Time        cmbUnit.add("Seconds"); //$NON-NLS-1$        cmbUnit.add("Minutes"); //$NON-NLS-1$        cmbUnit.add("Hours"); //$NON-NLS-1$        cmbUnit.add("Days"); //$NON-NLS-1$        cmbUnit.add("Weeks"); //$NON-NLS-1$        cmbUnit.add("Months"); //$NON-NLS-1$        cmbUnit.add("Quarters"); //$NON-NLS-1$        cmbUnit.add("Years"); //$NON-NLS-1$        if (grouping.getGroupType() != null && grouping.getGroupType().equals("Date/Time") //$NON-NLS-1$            && grouping.getGroupingUnit() != null)        {            cmbUnit.setText(grouping.getGroupingUnit());        }        else        {            cmbUnit.select(0);        }        lblUnit.setEnabled(bEnableUI & cmbType.getText().equals("Date/Time"));        cmbUnit.setEnabled(bEnableUI & cmbType.getText().equals("Date/Time"));        // Populate grouping aggregate expression combo        cmbAggregate.setItems(PluginSettings.instance().getRegisteredAggregateFunctions());        if (grouping.getAggregateExpression() != null)        {            cmbAggregate.setText(grouping.getAggregateExpression());        }        else        {            cmbAggregate.select(0);        }        lblAggregate.setEnabled(bEnableUI);        cmbAggregate.setEnabled(bEnableUI);    }