In Java 9, factory methods are introduced for collections API. Below are examples. Example:
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//Example import java.util.List; import java.util.Map; import java.util.Set; public class CollectionsFactoryMethods { public static void main(String[] args) { /* * List factory method */ List<String> numberList = List.of("One", "Two", "Three"); System.out.println(numberList); /* * Set factory method */ Set<String> numberSet = Set.of("One", "Two", "Three"); System.out.println(numberSet); /* * Map factory method */ Map<String, String> numberMap = Map.of("1", "One", "2", "Two", "3", "Three"); System.out.println(numberMap); } } |
Output:
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[One, Two, Three] [One, Two, Three] {3=Three, 2=Two, 1=One} |