Java Coding Problems

Problem 5 (immutable)

Let's now create a list of ImmutableMelon via Collections.unmodifiableList() and the List.of() methods:

private static final ImmutableMelon MELON_1   = new ImmutableMelon("Crenshaw", 2000);private static final ImmutableMelon MELON_2   = new ImmutableMelon("Gac", 1200);private static final List<ImmutableMelon> LIST   = Collections.unmodifiableList(Arrays.asList(MELON_1, MELON_2));private static final List<ImmutableMelon> LIST   = List.of(MELON_1, MELON_2);

So, is the list unmodifiable or immutable? The answer is immutable. Mutator methods will throw UnsupportedOperationException, and we cannot mutate the instances of ImmutableMelon.

As a rule of thumb, a collection is unmodifiable if it is defined via unmodifiableFoo() or ...