Lesson 13 - StreamAPI in Java - Closing stream methods

Java Collections and Streams StreamAPI in Java - Closing stream methods

In the previous lesson, StreamAPI in Java - Modifying stream methods, we learned stream methods that modify the stream in a specific way. In today's Java tutorial, we're going to look at closing stream methods, which we usually use to finish work with the stream and possibly get a result.

Closing stream methods

As we've mentioned at the beginning, we're going to focus on methods, that no longer return a stream, but a value or a data collection.

The findFirst() Method

The method's signature is as follows:

findFirst()

The method tries to find the first element that matches all previously applied filters and properties. The return value is of the Optional<T> type, because there may be no element matching the applied filters.

In the first example, we're going to search for the first name that's longer than 4 characters:


 

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In this Java tutorial, we'll learn about stream methods we use to close streams and get the results.

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