### Question:
SheetConfig { public int getIndex() { return index; } private  SheetConfig(); int getIndex(); String getName(); boolean isIndexSet(); boolean isNameSet(); static SheetConfig fromAnnotation(Sheet sheet);  }### Answer:
@Test public void createSheetConfigWithOnlyIndexShouldSetIndexFlag() { assertEquals(0, new SheetConfig.Builder().index(0).build().getIndex()); }