### Question:
NamedListWrapper { public List<NamedListWrapper> getListOfNamedListsAssertNotEmpty(String key) { List list = namedList.getAll(key); if (list.isEmpty()) { throw new IllegalArgumentException(this.exceptionMessage); } List<NamedListWrapper> toReturn = new ArrayList<>(); for (Object obj : list) { if (obj instanceof NamedList) { toReturn.add(new NamedListWrapper((NamedList) obj, this.exceptionMessage)); } else { throw new IllegalArgumentException(this.exceptionMessage); } } return toReturn; } private  NamedListWrapper(final NamedList namedList, final String exceptionMessage); static NamedListWrapper create(final NamedList namedList, final String exceptionMessage); NamedListWrapper getNamedListOrElseThrow(String key); List<NamedListWrapper> getListOfNamedListsAssertNotEmpty(String key); String getStringOrElseThrow(String key); int getOrDefaultInteger(String key, int defaultValue); BigDecimal getOrDefaultBigDecimalAssertNotNegative(String key, float defaultValue); BigDecimal getOrDefaultBigDecimal(String key, float defaultValue);  }### Answer:
@Test public void testListOfNamedListsIsEmpty() { exceptionRule.expect(IllegalArgumentException.class); exceptionRule.expectMessage(message); namedListWrapper.getListOfNamedListsAssertNotEmpty(unknown); }