@Override
    public boolean equals(Object o) {
        if (o == this)
            return true;
        if (!(o instanceof Set))
            return false;
        Collection<?> c = (Collection<?>) o;
        if (c.size() != size())
            return false;
        try {
            return containsAll(c);
        } catch (ClassCastException unused)   {
            return false;
        }
    }
This is a hash set which can be snapshotted.
<br>
See {@link SnapshottableHashTable} for more details about the implementation.
<br>
This class requires external synchronization.  Null values are not supported.

@param <T>   The value type of the set.
server-common/src/main/java/org/apache/kafka/timeline/TimelineHashSet.java