What are Java Streams and Collectors?

Can you explain what Java Streams and Collectors are?

Sure! Java Streams are a sequence of elements that can be processed in a functional style. Collectors are used to accumulate the elements of a stream into a collection.

How do I use Collectors to group elements in a Stream?

You can use the Collectors.groupingBy() method to group elements by a classifier function. For example, stream.collect(Collectors.groupingBy(Person::getAge)) groups people by their age.

Can you give me an example of using Streams and Collectors together?

Absolutely! Here's a simple example: List<String> names = people.stream().map(Person::getName).collect(Collectors.toList()); This converts a list of Person objects to a list of their names.

What are some other useful Collectors?

Some useful Collectors include Collectors.toList(), Collectors.toSet(), and Collectors.joining() for concatenating strings.