Java-get most common element in a list

In statistics, this is called the “mode”. A vanilla Java 8 solution looks like this:

Stream.of(1, 3, 4, 3, 4, 3, 2, 3, 3, 3, 3, 3)
      .collect(Collectors.groupingBy(Function.identity(), Collectors.counting()))
      .entrySet()
      .stream()
      .max(Map.Entry.comparingByValue())
      .ifPresent(System.out::println);

Which yields:

3=8

jOOλ is a library that supports mode() on streams. The following program:

System.out.println(
    Seq.of(1, 3, 4, 3, 4, 3, 2, 3, 3, 3, 3, 3)
       .mode()
);

Yields:

Optional[3]

For simplicity’s sake, I omitted using BigDecimal. The solution would be the same, though.

(disclaimer: I work for the company behind jOOλ)

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