WEBVTT 00:00.080 --> 00:00.590 Hi everyone. 00:00.590 --> 00:01.160 Welcome back. 00:01.160 --> 00:06.050 In this lecture we are going to learn about the exhaustive nature of the enhanced switch. 00:06.050 --> 00:08.240 So what is the exhaustive nature means? 00:08.240 --> 00:14.690 Is that any switch expression that we write must handle every possible scenario for your input type. 00:14.690 --> 00:21.020 So in this case for the month, we have September, April, June, November and February. 00:21.020 --> 00:22.580 And then we have default here. 00:22.580 --> 00:22.910 Right. 00:22.910 --> 00:28.190 So in this case if I remove default the code will start to complain which means we are missing out some 00:28.190 --> 00:28.790 scenarios. 00:28.790 --> 00:32.330 So this is the exhaustive nature of switch expression. 00:32.330 --> 00:39.080 And we can actually avoid using default if we provide all the matching conditions that is possible for 00:39.080 --> 00:40.490 this switch expression. 00:40.490 --> 00:43.790 That is exactly what I am going to explain in this specific lecture. 00:43.790 --> 00:47.600 So in here what we are going to do I'm going to create another function. 00:47.600 --> 00:49.460 And the function name is going to be v3. 00:49.460 --> 00:52.430 So in here what I'm going to do I'm going to remove the default. 00:52.430 --> 00:56.810 And then instead of default we can provide all the different possible months. 00:56.810 --> 01:04.960 So in this case it's going to be January March, May, July, August, October and December. 01:04.960 --> 01:10.420 And then if we provide this value as 31, then in this case, the compiler is not going to complain. 01:10.450 --> 01:16.330 What this means is that for the input that we are using in our switch expression, we have covered the 01:16.330 --> 01:18.040 all possible scenarios. 01:18.040 --> 01:24.130 This is one of the nicest thing about the switch expression and the exhaustive nature of the enhanced 01:24.130 --> 01:25.090 switch expression. 01:25.090 --> 01:31.480 So if all the possible enum constants are present in a switch expression for this specific example, 01:31.480 --> 01:37.450 and the match is total, and it is not necessary for the default case to be included for the compiler 01:37.450 --> 01:38.350 to be happy. 01:38.350 --> 01:43.330 If you cover all the scenarios, the compiler will be happy to compile the code without the use of the 01:43.330 --> 01:44.260 default block. 01:44.290 --> 01:45.700 I hope the explanation is clear. 01:45.730 --> 01:46.600 Now what we will do. 01:46.630 --> 01:51.820 We will quickly go ahead and write the test that's going to invoke the get days v3 function. 01:51.850 --> 01:56.860 So in this case we can pretty much use the same test block, just that we need to change the function 01:56.860 --> 02:00.830 to the get days is v three and get this v three over here. 02:00.860 --> 02:05.810 Now if I go ahead and execute this function, as long as it returns me the green signal, that means 02:05.810 --> 02:08.120 our code is still working as expected. 02:08.150 --> 02:13.400 Now let's go ahead and execute the whole test covering all the different test cases that we have. 02:13.430 --> 02:13.970 There we go. 02:14.000 --> 02:18.350 We got a green check mark for all the test cases that are part of this test. 02:18.350 --> 02:22.700 So well this is the exhaustive nature of the enhanced switch block. 02:22.730 --> 02:24.230 You don't need to provide the default. 02:24.230 --> 02:28.940 If you cover all the possible inputs that can be passed to this switch expression. 02:28.970 --> 02:30.110 So a quick recap here. 02:30.140 --> 02:32.420 We learned about the exhaustive nature. 02:32.420 --> 02:38.750 And then we also learned about how to provide a lambda body for a case which covers multiple code statements. 02:38.750 --> 02:45.260 And as a whole, we have learned about how to use switch as an expression using the enhanced switch 02:45.260 --> 02:45.650 block. 02:45.950 --> 02:49.940 Well, this wraps the enhanced switch feature that's part of the modern Java. 02:49.970 --> 02:54.770 I hope you all had fun coding this specific feature and learning this specific feature. 02:54.800 --> 02:56.150 This marks the end of this lecture. 02:56.180 --> 02:57.380 Thank you for watching.