### Question:
PanLine extends JPanel { public String getCustomWidthUnit() { EnumWidthUnit enumWidthUnit = (EnumWidthUnit) comboBoxWidthUnit.getSelectedItem(); return enumWidthUnit.getXmlValue(); } PanLine(); String getAlign(); String getThickness(); String getCustomWidth(); String getCustomWidthUnit(); String getColor(); void setAlign(EnumAlign enumAlign); void setThickness(String thickness); void setCustomWidth(String width); void setCustomWidthUnit(EnumWidthUnit enumWidthUnit); void setColor(String hexValue);  }### Answer:
@Test public void testGetCustomWidthUnit() { JComboBox comboBox = new JComboBox(); for (EnumWidthUnit enumWidthUnit : EnumWidthUnit.values()) { comboBox.addItem(enumWidthUnit); } comboBox.setSelectedIndex(1); Whitebox.setInternalState(panLine, "comboBoxWidthUnit", comboBox); String actual = panLine.getCustomWidthUnit(); String expected = EnumWidthUnit.values()[1].getXmlValue(); assertEquals(expected, actual); }