How can I filter a list in Java?

How can I filter a list in Java?

You can use the Stream API to filter a list in Java. For example, you can use list.stream().filter(condition).collect(Collectors.toList()).

Can you show me an example with a list of integers?

Sure! Here's an example: List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5); List<Integer> evenNumbers = numbers.stream().filter(n -> n % 2 == 0).collect(Collectors.toList()); This will give you a list of even numbers.

What if I want to filter based on a custom object?

You can filter based on any property of your custom object. For instance, if you have a Person class, you can filter like this: people.stream().filter(p -> p.getAge() > 18).collect(Collectors.toList());.

Is there a way to filter in place without creating a new list?

Yes, you can use Iterator to remove elements in place. For example: Iterator<Person> it = people.iterator(); while (it.hasNext()) { if (it.next().getAge() <= 18) { it.remove(); } }.