On 4/28/20 9:48 PM, Jason Mehrens wrote:
Looks like It is intentional that unmodifiable queues are not present. See:
https://bugs.openjdk.java.net/browse/JDK-5030930. The same logic would have
been used for when Deque was added in the following release.
Good find.
Looking at the Queue interface, it adds four mutator methods and two access
methods: element() and peek(). These latter two provide only a tiny bit of
convenience over an iterator, so an unmodifiable Queue provides hardly any value
over Collection. Thus the rationale in JDK-5030930 for not providing an
unmodifiable Queue makes sense.
Deque is considerably richer than Queue, not only in mutator methods. It also
adds access methods for both ends (null-returning and throwing), with better
names, plus a descending iterator. That might make it worthwhile reconsidering
an unmodifiable Deque.
s'marks
