.stream().filter

The method `.filter()` is a method in Java 8's Stream API that takes a Predicate as an argument and returns a new Stream that contains only the elements that satisfy the given Predicate.

Here's an example of how to use `.filter()`:

List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);

List<Integer> evenNumbers = numbers.stream()
                                    .filter(n -> n % 2 == 0)
                                    .collect(Collectors.toList());

System.out.println(evenNumbers); // Output: [2, 4, 6, 8, 10]

In this example, we have a list of integers `numbers`. We create a Stream from this list using the `.stream()` method. We then apply the `.filter()` method to this Stream with a Predicate that checks if the number is even. This creates a new Stream that contains only the even numbers. Finally, we collect the filtered elements into a new List using the `.collect()` method.