Hello, in this video, we are going to look at the if statement, which is part of decision making also called conditional statement. So if I'm allowed you to check if a condition is true, if a condition is true, then you're likely to run this code. If not, then you don't end up with code. So it's great. if let's say, the user input something, maybe it's an option from a menu, and maybe the option is to go to if it's in the case of game, it goes to, you know, to play mode. If they've chosen the option, you can check the next statement.
You got to to play mode, if not, you do something else. Okay, so we're going to create a variable so we'll say int equals four, and we are going to do anything. So this is the structure of it. So if r is equal to four, so the structure is you put the keyword if you put two brackets And inside here you put your condition if this results in a value of truth, or if it doesn't equal four, then it runs the code within these curly braces. So output system, dot out dot print ln. Yay.
So if we run it, say Yay, value is 445. Change to five, however, we'll see nothing gets printed out, because when it goes to is 90 does equal to four. So it's saying to five equal four, No, it doesn't. So this returns false. And because it's false, this, you know, statement isn't met, you know, at its core, that's all a if statement is there are sort of two other branches will lock up and you can add analysis. So an analysis allows you to say, if you know this condition is not true let's check for another condition to say if i equals equals five.
I'll copy this time. Good. Boy. So if I run it Okay, that's running again. But yeah, not good but running fine. If I put this back yay value is four it only goes within here.
So to solve a demonstrate this forward to do the Greater Lansing greater than symbol so if premise one crease this number. So if I say if i greater than four, so if I do five I mean come in to change this or so I'm just saying this ignore what he actually says. So, if it is greater than five, which it is, it does, you know that you are thinking if you are satisfied on 22, which technically this condition comes out as true and this one for 22 is greater than five then 22 is greater than 10. He should print out both lines but it only prints out the first one because, if you do else this will ever only get checked if the previous statement is false. But if we were to just do a regular assignment, both conditions will be checked else only yes check if the previous condition in that branch or false?
And what you can also do for our changes back to you know what it used to be called put the phone you can also have the NOAA house if you cannot know how many houses have you want, like so we could do six. Now let's print out six. So this one like one run x okay I need to change the value. So what it does it goes through this is a is equal to 436 equals four No, I'll say is equal five so it's 65. Now, is it 636 equal to six? Yes it is values are validated true and I print this line at the final branch you can look at it out.
So there is no keyword or no brackets after this. This is just saying if all allows file so every other condition within this if you know conditional statement without us false just pull back to this line going for the System dot out dot print. I'll just say all back and if I were to run it right now will print out six if I were to change to seven or anything, four Five and six eight princess fallback, so that's, you know the if statements in general. One last thing on will actually show you is you can add multiple conditions within any of these branches to do that you separated by either the double end or double, you know, vertical pipe and we covered this in the operator video, but they go blind. Basically they first of all, I thought How to arrange all in greater than five.
And I've never honestly 10 we print this. So what this basically saying, you see is greater than four or less than 10 are the valid values of 5678 and 934 or 5678 9% integer, we can't have decimals, those are the absolute valid values. And this double ampersand means that this has to validate is true. And this has to validate is true. So if I were to just look at Libya 741 it says Yay, value is four. So you know, it goes into here.
If for example, I would change this to 11. He goes into fallback because both conditions are not true. But if I were to do it like this the first one will know for integrity Does AI is AI greater than four? Yes, it is. Anything or in less than 10 ai is isn't less than 10. But on request one of the conditions to validate as true, and you can actually add in many of these conditions as you want and you're doing fine.
You can add as many as you want or as little as you want. So that's it for the if statements within you know, the conditional decision making realm. If you have any questions, feel free to reach out. There will be source code alongside this video, or a GitHub page and I look forward to seeing you in the next awesome Java video.