Java 8 convert List to Set

• List

List integerList = Arrays.asList(1, 2, 3, 4, 5);

• List To Set : Implementation of set is hidden under the implementation which is HashSet

Set integerSet = integerList.stream().collect(Collectors.toSet());


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[addToAppearHere]

• To Retrieve a specific Implementation of Hash Set

In this example we retrieve LinkedHashSet

 LinkedHashSet set1 =  integerList.stream()
                                  .collect(
                                       LinkedHashSet::new,
                                       (objects, integer) -> ((Set)objects).add(integer),
                                       (objects, objects2) -> ((Set)objects).addAll(objects2)
                                   );
        
set1.stream().forEach(System.out::println);


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