WEBVTT 00:00.870 --> 00:01.440 Hi everyone. 00:01.440 --> 00:02.790 Welcome back to this tutorial. 00:02.790 --> 00:07.650 In this tutorial, we will explore some more functions of streams API. 00:07.680 --> 00:13.470 The functions are going to be distinct count and sorted distinct returns. 00:13.500 --> 00:20.520 A unique set of elements from the stream count returns along with a total number of elements in that 00:20.520 --> 00:22.560 particular stream sort. 00:22.560 --> 00:25.230 It is going to sort the elements in the stream. 00:25.320 --> 00:27.780 Let's go ahead and code these scenarios. 00:29.160 --> 00:35.490 Then here what I'm going to do, I'm going to use the same flatmap example class in here. 00:36.000 --> 00:40.050 I'm going to run this example and then see and then check the result basically. 00:40.080 --> 00:43.740 So here, if you take a look at it, let's consider swimming. 00:43.740 --> 00:52.950 Swimming is a repeated in many places because the way we have built this pipeline is get all students 00:52.950 --> 00:59.820 and get all the activities of the students and then consolidate and build that as a list. 00:59.820 --> 01:01.260 That's what we are doing here. 01:01.260 --> 01:09.240 Now, let's say I want to know what are the unique set of activities that all the students are participating. 01:09.240 --> 01:13.530 Basically, I want to know out of all these, I don't want any duplicates. 01:13.560 --> 01:17.370 What are the unique activities that students are participating? 01:17.400 --> 01:21.210 The way to achieve that is by calling. 01:22.350 --> 01:22.980 Distinct. 01:23.010 --> 01:31.230 If we call distinct, basically it is going to perform that unique operation and then return you the 01:31.230 --> 01:33.480 result with the unique activities. 01:33.510 --> 01:34.210 What I'm going to do. 01:34.230 --> 01:36.780 I'm going to run this example right now. 01:36.780 --> 01:40.020 If you take a look at this result, it has many duplicates. 01:40.020 --> 01:43.590 So for swimming, there are many instances of that available. 01:43.590 --> 01:44.460 In the result. 01:44.510 --> 01:45.960 We take a look at the basketball. 01:45.960 --> 01:48.960 There are many instance of that available in the result. 01:48.960 --> 01:51.510 I'm going to run this now and then check the result. 01:51.600 --> 01:57.900 So the only thing that I only change that I made here is that I added this distinct function as part 01:57.900 --> 01:59.220 of the stream pipeline. 01:59.980 --> 02:00.790 Run this. 02:01.570 --> 02:02.500 There you go. 02:02.530 --> 02:09.190 What it did was it performed the distinct operation for all the elements in that stream. 02:09.190 --> 02:13.430 This is equivalent to the distinct that we use in the SQL queries. 02:13.450 --> 02:20.650 So the result is that these are the unique set of activities that students are participating in that 02:20.650 --> 02:22.330 from that student database class. 02:22.510 --> 02:28.270 Now what I want is I want to know what are all the the total number of activities right now. 02:28.270 --> 02:31.810 We know the unique activities. 02:31.810 --> 02:32.360 Right. 02:32.380 --> 02:38.530 I want to know what is the total number of activities that are supported by this school, meaning supported 02:38.530 --> 02:40.360 by this student database. 02:40.600 --> 02:43.000 What I'm going to do I'm going to copy this. 02:45.040 --> 02:49.250 And then I'm going to name this one as get student. 02:50.240 --> 02:51.410 Activities. 02:52.240 --> 02:52.540 Don't. 02:53.290 --> 02:53.830 Okay. 02:54.280 --> 02:57.010 And this is going to return a long. 02:57.220 --> 02:58.630 That's what it is going to do. 03:00.290 --> 03:03.580 I'm going to name this one as long. 03:06.280 --> 03:06.990 Number of. 03:09.010 --> 03:09.700 Couldn't. 03:10.850 --> 03:11.630 Activities. 03:12.930 --> 03:13.350 Right. 03:13.350 --> 03:18.900 And in here, instead of select a list, I'm going to use the method count. 03:19.840 --> 03:22.810 Count is going to give you the total number of. 03:25.040 --> 03:26.330 Elements in that stream. 03:26.490 --> 03:30.500 So this is going to again return a stream of string. 03:32.540 --> 03:33.080 But. 03:36.460 --> 03:37.960 Distinct function. 03:42.880 --> 03:43.960 Performed, right? 03:46.950 --> 03:51.180 Billing mistake here with distinct, distinct function performed on top of it. 03:51.210 --> 03:53.310 Now if I call this. 03:55.460 --> 03:56.380 Call this one. 03:56.390 --> 04:03.440 Now, if I call this what it is going to give, it is going to give me the total number of. 04:04.230 --> 04:05.550 Activities that. 04:06.680 --> 04:08.050 Students are participating. 04:08.060 --> 04:11.210 So the total number of activities is nine. 04:11.240 --> 04:15.440 I can go ahead and calculate this by manually. 04:16.010 --> 04:21.530 Let's say this is one, two, three, four, five, six, 789. 04:21.560 --> 04:22.820 I can manually do it. 04:22.820 --> 04:25.670 But the idea here is I want the system. 04:25.670 --> 04:32.180 I want the streams API to tell me how many distinct activities are available as part of that student 04:32.180 --> 04:33.230 database class. 04:33.260 --> 04:34.190 Now. 04:35.010 --> 04:38.220 What I want is here if you take a look at the result. 04:38.250 --> 04:41.010 The result is not in alphabetical order. 04:41.010 --> 04:44.490 I want the result to be in alphabetical order. 04:44.490 --> 04:48.870 In those kind of scenarios, there is a handy function which is available. 04:49.050 --> 04:51.180 If you take a look at it, it is called sorted. 04:51.450 --> 04:54.300 If I perform sorted, it is going to. 04:55.740 --> 04:57.870 Sort it in natural order. 04:57.870 --> 05:00.000 Basically, it is going to perform. 05:00.960 --> 05:03.030 It is going to sort the result in alphabetical order. 05:03.030 --> 05:04.830 Let's run this result and then check. 05:04.830 --> 05:07.050 So here the result is not sorted. 05:07.050 --> 05:11.610 As soon as I run this example, it is going to sort the result because I have added the sorted method 05:11.610 --> 05:12.150 here. 05:13.050 --> 05:14.610 And this example and then check. 05:15.690 --> 05:16.220 There you go. 05:16.230 --> 05:17.130 It sorted. 05:17.130 --> 05:21.240 The result in the alphabetical order starts with A and ends with Y. 05:22.860 --> 05:29.430 But these are all the handy functions which are available on stream API supports in order to get your 05:29.430 --> 05:30.990 desired result. 05:31.020 --> 05:33.330 With this we came to the end of this tutorial. 05:33.360 --> 05:34.590 Thank you for watching.