### Question:
ObjectMultistack { public ValueWrapper peek(String keyName) { return getTopAndMaybeRemove(keyName, false); } ObjectMultistack(); void push(String keyName, ValueWrapper valueWrapper); ValueWrapper pop(String keyName); ValueWrapper peek(String keyName); boolean isEmpty(String keyName);  }### Answer:
@Test void testPeekingEmptyEntry() { assertThrows(EmptyMultistackEntryException.class, () -> new ObjectMultistack().peek("key")); }