To use the Collectors class in Java, you will need to import it from the java.util.stream package. Here is an example of how you can do this in your code:
import java.util.stream.Collectors;
Once you have imported the Collectors class, you can use it to perform various operations on streams, such as collecting elements from a stream into a list or set, or performing reduction operations. Here is an example of using the Collectors class to collect the elements of a stream into a list:
List<String> words = Stream.of("apple", "banana", "cherry")
.collect(Collectors.toList());
The Collectors class provides many static factory methods for creating common types of collectors, such as toList, toSet, and toMap. You can also use the Collectors class to create custom collectors by using its reducing and groupingBy methods.