Java中的LinkedHashSet集合解读

LinkedHashSet()

LinkedHashSet(int initialCapacity, float loadFactor)

public boolean add(E e)

public boolean remove(Object o)

public void clear()

public int size()

@Test
    public void test1() {
        Set<Integer> set = new LinkedHashSet<>();
        set.add(5);
        set.add(4);
        set.add(5);
        set.add(3);
        set.add(1);
        set.add(9);
        //正顺序遍历
        System.out.print("遍历：");
        set.forEach(item -> {
            System.out.print(item + "  ");
        });
    }

@Test
    public void test2() {
        Set<Integer> set = new LinkedHashSet<>();
        set.add(null);
        set.add(5);
        System.out.println(set);
    }

public class LinkedHashSet<E>
    extends HashSet<E>
    implements Set<E>, Cloneable, java.io.Serializable {
    public LinkedHashSet(int initialCapacity, float loadFactor) {
        super(initialCapacity, loadFactor, true);
    }
    public LinkedHashSet(int initialCapacity) {
        super(initialCapacity, .75f, true);
    }
    public LinkedHashSet() {
        super(16, .75f, true);
    }
    public LinkedHashSet(Collection<? extends E> c) {
        super(Math.max(2*c.size(), 11), .75f, true);
        addAll(c);
    }
}