package collections;

import java.util.AbstractMap;

import java.util.Arrays;

import java.util.Deque;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Iterator;

import java.util.Map;

import java.util.Map.Entry;

import java.util.NavigableMap;

import java.util.NavigableSet;

import java.util.Set;

import java.util.SortedSet;

import java.util.Spliterator;

import java.util.TreeSet;

import java.util.concurrent.ConcurrentSkipListSet;

public class SetDemo {

public static void main(String[] args) {

//hashSet is the unordered collection which help me store multiple unique objects together on random sequence

/*

* hashset not allow duplicate

* it is unordered

* hashset not follow insertion order

* hashset internally use hashmap means whenever we add element it will be add as a key in hashmap

* because of key cant be duplicate

* and every time it will generate hash value of element and check if any key contains with this hash value if present it will replace by new key

*

* it allow null object

* but if perform some operations like removeIf method we get NullPointerException if there is any element present with null*/

HashSet<Integer> hashset=new HashSet<Integer>(Arrays.asList(10,30,45,23,10,30,45,56,78,12));

HashSet<Integer> hashset1=new HashSet<Integer>(Arrays.asList(10,30,45,23,10,30,45,56,78,12));

System.out.println(hashset);

hashset.add(99);

hashset.add(90);

hashset1.add(null);

//hashset.removeIf((a)->a%2==0);

System.out.println(hashset.retainAll(hashset1));

System.out.println(hashset);

Iterator<Integer> i=hashset1.iterator();

Spliterator<Integer> sp=hashset1.spliterator();

System.out.println(sp.characteristics());

SortedSet<Integer> n=new ConcurrentSkipListSet<Integer>();

n.add(10);

n.add(20);

n.add(1);

n.add(55);

n.add(13);

n.add(78);

System.out.println(n);

NavigableSet<Integer> set=new TreeSet<Integer>(n);

set.add(20);

set.add(11);

set.add(89);

System.out.println(set.floor(11));

System.out.println(set.ceiling(11));

System.out.println(set.tailSet(11,false));

System.out.println(set.higher(11));

System.out.println(set.first());

System.out.println(set.last());

System.out.println(set.lower(11));

System.out.println(set.subSet(1, 2));

System.out.println(set.pollFirst());

System.out.println(set.pollLast());

System.out.println(set.headSet(15));

//System.out.println(set.descendingIterator());

System.out.println(set.descendingSet());

System.out.println(set);

}

}