### Question:
AbstractOptionHelper implements OptionHelper { public static String getChartBaseResourceKey(String chartId) { return "chart." + chartId + "."; } AbstractOptionHelper(Chart chart); static String getChartBaseResourceKey(String chartId); @Override String getChartBaseResourceKey(); @Override IModel<String> getChartLabelResourceModel(String subKey); @Override ChartOptions addTitle(ChartOptions parent); @Override ChartOptions addSubTitle(ChartOptions parent); @Override ChartOptions addDualAxisOptions(ChartOptions parent, String[] axisNames, String[] seriesMapping); @Override ChartOptions addDualAxisOptions(ChartOptions parent,
            String[] axisNames, String[] seriesMapping,
            OptionModifier[] axisModifiers, OptionModifier[] seriesModifiers); @Override ChartOptions addDualAxisOptions(ChartOptions parent, String[] axisNames, String[] seriesMapping, String[] axisTitles);  }### Answer:
@Test public void testGetChartBaseResourceKey() { AbstractOptionHelper instance = new AbstractOptionHelperImpl(chart); String expResult = "chart.myChart."; String result = instance.getChartBaseResourceKey(); assertEquals(expResult, result); }