Java interview questions

Implement entryPoint(List<String> words) that returns a Map<String, Integer> telling how many times each word occurs. The comparison is exact (case-sensitive). null entries are ignored.

In one or two sentences each: what is a List, what is a Set, and what is a Map? Give me one everyday situation where you would pick each one.

Compare ArrayList and LinkedList. Which operations are cheap on each, and why is ArrayList almost always the right default even for workloads with insertions in the middle?

Define an enum Day with the seven days of the week (MONDAY through SUNDAY) and a method boolean isWeekend() that returns true for SATURDAY and SUNDAY and false for the rest, implemented with a modern arrow-form switch expression (not a chain

What is a Java enum, really, under the hood? Why is it preferred over a set of public static final int constants for something like a set of days of the week?

Each inner list in points holds exactly two integers, an x and a y coordinate. Implement entryPoint(List<List<Integer>> points) returning how many distinct points there are. Model a point as your own type (a record is ideal) and let a HashSet do the de-duplication; the point