Java Collections

 https://www.programcreek.com/2014/04/check-if-array-contains-a-value-java/

1. Four Different Ways to Check If an Array Contains a Value

1) Using List:

public static boolean useList(String[] arr, String targetValue) { return Arrays.asList(arr).contains(targetValue); }

2) Using Set:

public static boolean useSet(String[] arr, String targetValue) { Set<String> set = new HashSet<String>(Arrays.asList(arr)); return set.contains(targetValue); }

3) Using a simple loop:

public static boolean useLoop(String[] arr, String targetValue) { for(String s: arr){ if(s.equals(targetValue)) return true; } return false; }

4) Using Arrays.binarySearch():
binarySearch() can ONLY be used on sorted arrays. If the array is sorted, you can use the following code to search the target element:

public static boolean useArraysBinarySearch(String[] arr, String targetValue) { int a = Arrays.binarySearch(arr, targetValue); if(a > 0) return true; else return false; }

Comparator<Arrow> cmp = Comparator
        .comparing(Arrow::getWeight)
        .thenComparing(Arrow::getCount, Comparator.reverseOrder())
        .thenComparing((a, b) -> Character.compare(a.ch, b.ch));

listChar.sort(cmp);

 
List<Employee> sortedEmployees = employees.stream()
                .sorted(cmp).collect(Collectors.toList());

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 Collections.sort(scores, new Comparator<Score>() {

        public int compare(Score o1, Score o2) {
            return o2.getScores().get(0).compareTo(o1.getScores().get(0));
        }
    });

Collections.sort(scores, (s1, s2) -> { return s1 - s2; });

Collections.binarySearch(cats, key);

String s = list.stream().map(Objects::toString)
.sorted(Comparator.reverseOrder()).collect(Collectors.joining(""));

int[] arr = {1,2,3};

var list = Arrays.stream(arr).boxed().toList();

list.subArray(int begin, int end)