1 00:00:00,540 --> 00:00:02,240 Hello everyone. In this session 2 00:00:02,240 --> 00:00:03,250 let us look at the TreeSet. 3 00:00:03,870 --> 00:00:05,730 TreeSet is an important implementation 4 00:00:05,730 --> 00:00:07,460 of SortedSet interface. 5 00:00:07,840 --> 00:00:11,230 It is a sorted type of set, very 6 00:00:11,230 --> 00:00:13,100 similar to HashSet but the difference 7 00:00:13,100 --> 00:00:15,960 is, it is an ordered collection and elements 8 00:00:15,970 --> 00:00:19,380 are sorted in the ascending order by default. 9 00:00:19,420 --> 00:00:21,740 So, inside a TreeSet, when we add 10 00:00:21,740 --> 00:00:23,810 the elements, those are automatically 11 00:00:23,810 --> 00:00:25,570 sorted in the ascending order. 12 00:00:25,580 --> 00:00:27,240 So, let's create an object of TreeSet. 13 00:00:27,390 --> 00:00:31,100 Let us use the set interface to create the object, 14 00:00:31,110 --> 00:00:36,640 say set1 = new TreeSet. 15 00:00:38,240 --> 00:00:41,360 Import the TreeSet and import the set interface. 16 00:00:42,040 --> 00:00:43,780 Now, to create the object of a set, 17 00:00:44,020 --> 00:00:46,240 you can use the var keyword if you're 18 00:00:46,310 --> 00:00:49,350 using Java 10 or you can use the particular 19 00:00:49,350 --> 00:00:53,100 reference type like TreeSet or you can use the set 20 00:00:53,100 --> 00:00:55,250 interface because it is the parent interface. 21 00:00:55,740 --> 00:00:57,070 So, you can choose any of the ways. 22 00:00:57,300 --> 00:00:59,240 Now, let us add some elements to the set. 23 00:00:59,240 --> 00:01:02,360 Let us say I want to add some names. 24 00:01:03,140 --> 00:01:05,060 So, we have added four items, Rob, 25 00:01:05,060 --> 00:01:07,040 Bob, Andy, and Charls. 26 00:01:07,040 --> 00:01:10,650 And let us simply display the set over here. 27 00:01:11,540 --> 00:01:14,350 So, in this case we will see four elements 28 00:01:14,350 --> 00:01:16,560 in the list, but those will be sorted 29 00:01:16,570 --> 00:01:18,360 automatically in the ascending order. 30 00:01:19,040 --> 00:01:20,280 So, when we look at the output, 31 00:01:20,550 --> 00:01:22,330 the set is automatically sorted. 32 00:01:22,330 --> 00:01:23,850 So, A, B, C, and R. 33 00:01:25,140 --> 00:01:26,870 Let's add some other elements. 34 00:01:26,870 --> 00:01:30,720 Let's create another set , say set2 = 35 00:01:31,050 --> 00:01:35,250 to new TreeSet( ); integer. 36 00:01:35,640 --> 00:01:39,450 and let's quickly add some integer values. 37 00:01:39,840 --> 00:01:41,000 So, we have added some random 38 00:01:41,020 --> 00:01:43,040 integer values and let us also 39 00:01:43,040 --> 00:01:44,840 display the set2. 40 00:01:45,640 --> 00:01:47,790 So, in this case we can expect the set2 41 00:01:47,790 --> 00:01:50,290 also get sorted in the ascending 42 00:01:50,290 --> 00:01:51,490 order by default. 43 00:01:51,500 --> 00:01:53,590 So, that is the main difference in between 44 00:01:53,820 --> 00:01:56,310 the HashSet and TreeSet. 45 00:01:56,690 --> 00:01:58,690 In case of HashSet, it is not an ordered 46 00:01:58,890 --> 00:02:00,290 collection, in case of TreeSet, 47 00:02:00,420 --> 00:02:03,540 it is an ordered collection, but it is ordered 48 00:02:03,550 --> 00:02:05,560 in the sorted fashion. 49 00:02:05,570 --> 00:02:07,110 It sorts the elements automatically 50 00:02:07,310 --> 00:02:09,240 in the ascending order. Other than that, 51 00:02:09,250 --> 00:02:10,810 all methods are same, 52 00:02:11,009 --> 00:02:14,090 add, remove, clear, contents, very same to 53 00:02:14,169 --> 00:02:15,700 what we have seen in the HashSet, 54 00:02:16,300 --> 00:02:20,180 and union and intersection methods are similar, 55 00:02:20,620 --> 00:02:22,660 converting to list is also similar. 56 00:02:23,640 --> 00:02:25,930 Okay, so this is about the HashSet, 57 00:02:26,160 --> 00:02:28,540 LinkedHashSet, and TreeSet in Java, and there's 58 00:02:28,540 --> 00:02:30,660 also an interview question. Thank you.