Java Stream collect() Example

 In this tutorial, we will learn Java 8 Stream collect() terminal operation with an example.

The Java Stream collect() method is a terminal operation that starts the internal iteration of elements and collects the elements in the stream in a collection or object of some kind. 

Java Stream collect() Example

Here is a simple Java Stream collect() method example:
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class Main {
    public static void main(String[] args)
    {
        List<String> stringList = new ArrayList<String>();

        stringList.add("one");
        stringList.add("two");
        stringList.add("three");
        stringList.add("four");
        stringList.add("five");

        Stream<String> stream = stringList.stream();

        List<String> stringsAsUppercaseList = stream
                .map(value -> value.toUpperCase())
                .collect(Collectors.toList());

        System.out.println(stringsAsUppercaseList);

    }
}

Output:

[ONE, TWO, THREE, FOUR, FIVE]

Java Stream Methods/APIs Examples