rebizant

@Test
    void sampleTest() {
        int size = 5000000;
        List<String> data = new ArrayList<>(size);
        for (int i = 0; i < size; i++) {
            data.add("sample-value-" + i);
        }
        Cache cache = CacheFactory.prepareCache(data);
        FilteringHandler handler = new FilteringHandler(cache);
        List<String> attributesToRemove = data.subList(101, 100000);

rebizant

public List<String> getAttributes(String attribute, int quantity) {

        if (quantity <= 0) {
            return Collections.emptyList();
        }

        if (attribute == null) {
            return getElements(quantity, firstElement);
        }
        Node node = store.get(attribute);

rebizant

 public void removeAll(Collection<String> attributesToRemove) {
        attributesToRemove.forEach(key -> 
                           Optional.ofNullable(store.get(key))
                                   .ifPresent(node -> deletedMarker[node.index] = Boolean.TRUE));
    }

rebizant

public class FilteringHandler {

    private final Boolean[] deletedMarker;
    private final Node firstElement;
    private final Map<String, Node> store;

     public FilteringHandler(Cache cache) {
        this.firstElement = cache.getFirstEntry();
        this.store = cache.getStore();
        this.deletedMarker = new Boolean[store.size()];

rebizant

public class CacheFactory {

    public static Cache prepareCache(List<String> values) {

        if (values == null || values.isEmpty()) {
            return new Cache();
        }
        Map<String, Node> store = new HashMap<>(values.size());
        Node previousNode = new Node(values.get(0), 0);
        Cache cache = new Cache(store, previousNode);

rebizant

public class Cache {

    private final Map<String, Node> store;
    private final Node firstEntry;

    public Cache() {
        store = null;
        firstEntry = null;
    }

rebizant

class Node {

    String value;
    Integer index;
    Node next;

    Node(String value, Integer index) {
        this.value = value;
        this.index = index;
    }

rebizant

public class Main {

  public static void main(String[] args) throws Exception{
		 Main main = new Main();
		for(int i = 0; i < 1000 ; i++){

			main.convert(i);
		}
	}