How to Efficiently Convert Java Iterables to Streams?

Converting Iterables to Streams in Java 8

Problem:

You have an interface that returns an Iterable, and you want to use the Java 8 Stream API to manipulate the data. However, the Iterable does not support the stream() method.

Solution:

To convert an Iterable to a Stream without converting it to a List, you can use the StreamSupport.stream() method. This method takes a Spliterator object, which can be obtained from the Iterable's spliterator() method.

Here's an example of how to convert an Iterable to a Stream:

Iterable<T> iterable = ...;
Stream<T> stream = StreamSupport.stream(iterable.spliterator(), false);

Once you have a Stream, you can perform the usual stream operations such as filtering, mapping, and reducing.

Note:

The StreamSupport.stream() method provides a more efficient way to convert an Iterable to a Stream compared to using the spliteratorUnknownSize() method directly. The spliteratorUnknownSize() method always creates a new Spliterator object, which can be inefficient if the Iterable is already a collection. The StreamSupport.stream() method uses the existing Spliterator object from the Iterable, if available, resulting in improved performance.

The above is the detailed content of How to Efficiently Convert Java Iterables to Streams?. For more information, please follow other related articles on the PHP Chinese website!