What is the Java Stream API and how can I use it?

What is the Java Stream API and how can I use it?

The Java Stream API is a powerful feature introduced in Java 8 that allows you to process sequences of elements, such as collections, in a functional style. It provides methods for filtering, mapping, and reducing data.

Can you give me an example of using the Stream API to filter a list?

Sure! Here's a simple example:

List<String> names = Arrays.asList("Alice", "Bob", "Charlie", "David");
List<String> filteredNames = names.stream()
    .filter(name -> name.startsWith("A"))
    .collect(Collectors.toList());

This code filters the list to include only names that start with 'A'.

What are some common operations I can perform with the Stream API?

Common operations include filtering, mapping, sorting, and reducing. You can also perform operations like distinct, limit, and skip to manipulate the data further.

Is the Stream API efficient for large datasets?

Yes, the Stream API is designed to handle large datasets efficiently. It can leverage parallel processing, allowing operations to be performed concurrently, which can significantly improve performance.