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‫Instructor: Hi, within this lecture,

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‫we're going to learn about getters and setters.

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‫So when we deal with classes,

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‫we generally deal with constructors

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‫and we also deal with concepts called getters and setters.

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‫So what does getters and setters do?

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‫So let me change this address to private again,

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‫like we did in the previous lecture.

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‫And remember, when we did that,

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‫we couldn't reach homer.age here,

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‫not for changing and not for reading as well.

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‫As you can see, homer.age is not reachable,

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‫not for printing out here as well.

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‫Maybe if we want to print out this,

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‫maybe we want to read the value

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‫but maybe we don't want anyone to change this value.

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‫That's what getters and setters do.

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‫When we define getters,

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‫we actually can provide tools

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‫in order to read those values, get those values.

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‫And if we provide setters,

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‫then someone, some developer can actually change the value

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‫of those attributes as well.

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‫In order to create getters and setters,

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‫you can right click and say Generate one more time,

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‫and choose getters and setters,

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‫and then choose everything from that list.

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‫And click OK.

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‫And as you can see, it creates some methods.

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‫So if you look at the methods closely, it's fairly easy.

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‫You can create it on your own.

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‫It says that public String,

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‫so it's returning a string.

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‫And in this case, it's returning name.

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‫Even though it's private,

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‫we can reach it from here

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‫because we are in the same class, right?

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‫So it's fairly easy.

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‫We are getting the name and we are setting the name.

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‫So as long as these getters and setters are public,

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‫we can actually reach those methods

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‫from MainActivity as well.

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‫So if we don't make them private,

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‫then we can reach those.

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‫And it doesn't make sense to make getters

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‫and setters private, okay?

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‫And if you come over here,

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‫we're still getting an error

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‫because we cannot reach name from the MainActivity

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‫since it's private, but we can reach getName method, right?

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‫So rather than printing out this,

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‫I'm gonna print out the homer.getName.

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‫So as you can see, now we see the methods as well,

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‫like getJob, getAge, getName.

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‫Now if I do that, I won't get any error.

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‫And if I run this, now I can reach the Home name

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‫and I can print it out.

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‫So maybe you want somebody to read those values

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‫but you don't want anything, anyone

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‫to change those values.

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‫For example, I can actually change the name

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‫of the Homer to like Homer Simpson

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‫with setName method.

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‫And if I print out one more time

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‫by using homer.getName,

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‫I can see Homer and then Homer Simpson consecutively

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‫in my Logcat like this.

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‫So if I don't want anyone to change the name

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‫once they have initialized it,

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‫then I can delete these setters.

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‫I can only have the getters over here

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‫or I can do vice versa for some reason.

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‫Okay, so this is what getters and setters are for.

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‫So if you see getters and setters, don't be surprised.

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‫They're not complicated.

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‫They're actually very, very easy but they are useful tools.

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‫So when you deal with a class,

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‫when you deal with a model,

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‫if you create some attributes,

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‫if you create some constructors,

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‫make sure you think that if you need setters or getters.

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‫If you need those, then just import them,

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‫like generate them and use them in a way that you want.

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‫If you don't need those, then of course,

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‫you're more than welcome to ignore it as well.

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‫And remember, we're printing out everything in this case

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‫but in a real-life example,

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‫we would just display them on the emulator,

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‫on the user interface as well.

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‫Now we're gonna stop here

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‫and we're gonna have some challenges

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‫and assignment in the next lecture.