1

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So in this way we did manage to concatenate these two string values together and here as you can see



2

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in the emulator these values are together here.



3

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OK.



4

00:00:11,610 --> 00:00:13,300

The name of my child is my child.



5

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So let's actually go inside this main activity that Java here as you can see the name of my child is



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my charts the color of my child is white the speed of my child is 40.



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The power of my child is 40 and the number of legs of my child is four and fight two.



8

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So hopefully that makes sense.



9

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And here inside is Kathe class as you can see of vidit use the power of inheritance in our class.



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OK.



11

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So please make sure that you write your codes in this way.



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If you want to be a professional and whatever will appear or if you want to actually apply for your



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dream job as an Android Developer and actually earn top money please write your code in this way.



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You need to actually to write your cards in this way in order to persuade the employers to employ you.



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00:01:06,650 --> 00:01:07,160

OK.



16

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If you write your code in this way everybody wants you to write that applications.



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OK.



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Because this way of writing code is the most professional way of writing good code.



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OK.



20

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So now let's actually go inside this Animal class and here let's actually create another method.



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OK.



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So the access modifier of this method is public and the return type of this method is it and the name



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of this method is evaluate Alamein value.



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OK.



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And that I put a pair of brackets after the name of that name.



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And then I open and close the Smurfette by using these curly braces.



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So now I want to actually return a value that specifies the animal's value.



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OK first let's actually create an integer variable and the name of this variable is the result.



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And then I put an assignment operator here and then I specify the value of our animal by actually multiplying



30

00:02:07,680 --> 00:02:14,460

the value of this amount of speed instance variable by the value of this amount of power instance variable.



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OK.



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So amount of speed instance variable multiplied by amount of power instance variable.



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And then I return disvalue return result.



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OK so now as you can see we've got this method inside this animal class and this cad's class actually



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inherits all of the features and behaviors that are declared as public.



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Inside the Animal class.



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OK.



38

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So I can actually access that method here.



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OK.



40

00:02:43,830 --> 00:02:45,680

So let's actually access that method.



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00:02:45,900 --> 00:02:50,920

And here we can actually again concatenate this value here with another value.



42

00:02:51,140 --> 00:02:55,560

So plus operator evaluates animal value.



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OK.



44

00:02:57,480 --> 00:03:02,200

So as you can see here we did manage to concatenate this value with other strings here.



45

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OK.



46

00:03:02,520 --> 00:03:09,540

So as you can see here inside this Animal class the Smurfette returns a value of type integer and in



47

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Java we can actually concatenate string values with integer values.



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00:03:15,300 --> 00:03:16,050

OK.



49

00:03:16,260 --> 00:03:21,810

So as you can see here we poods this plus operator in order to concatenate is string value.



50

00:03:22,000 --> 00:03:27,040

With this we have returned value of the Smurfit evaluate animal value.



51

00:03:27,180 --> 00:03:28,340

And if I had on my project.



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Now let's see what happens.



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So as you can see here now this value is outputted here.



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OK.



55

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Twelve hundred.



56

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OK.



57

00:03:36,330 --> 00:03:42,930

So at least 12 hundred is the result of multiplication of these are two numbers.



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Number 40 multiplied by number 30.



59

00:03:45,720 --> 00:03:53,490

OK so this number 40 here is the value of this speed amount of speed instance variable and this number



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first here is the value of this power instance variable and we multiplied these two values together



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00:04:00,150 --> 00:04:04,240

in order to actually specify the animal's value.



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OK twelve hundred.



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OK.



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00:04:06,420 --> 00:04:13,980

So here I can actually inside this math class I can actually specify what this number relates to by



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just actually putting another plus operator here.



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00:04:18,150 --> 00:04:23,040

And then I can put a strain of value here a string literal.



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And here I can't just save an animal value OK or chat's value.



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It doesn't really matter.



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And then I can actually put in a call in here and another space here.



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00:04:36,210 --> 00:04:41,380

And let's actually put another space here in order to separate these values here.



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So let's actually run our project again and see what happens.



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OK.



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As you can see now disvalue is outputted Hiroki animal value.



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Twelve hundred.



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OK.



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So hopefully that makes sense.



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00:04:53,490 --> 00:04:57,840

And now we want to actually talk about another axis modifier.



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So inside this animal pass as you can see we've got these are private instance variables and this math



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00:05:05,770 --> 00:05:14,500

class which inherits all of those instance variables and methods I cannot see those private instance



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00:05:14,500 --> 00:05:15,260

variables.



81

00:05:15,370 --> 00:05:15,930

OK.



82

00:05:16,060 --> 00:05:17,670

So there is a solution for that.



83

00:05:17,800 --> 00:05:18,390

OK.



84

00:05:18,430 --> 00:05:27,100

You can actually use the protected access modifier in order to allow the subclasses or the classes that



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00:05:27,130 --> 00:05:34,250

inherit from this class to actually access these instance variables.



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00:05:34,330 --> 00:05:36,060

So let's see how we can do that.



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00:05:36,370 --> 00:05:37,490

OK everyone.



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00:05:37,490 --> 00:05:42,100

Now as you can see this instance variables are declared as private.



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00:05:42,100 --> 00:05:43,570

Instance variables are OK.



90

00:05:43,780 --> 00:05:48,090

The access modifier of this instance variables is private.



91

00:05:48,370 --> 00:05:51,750

So inside this Kathe class you might actually create another method.



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00:05:51,760 --> 00:05:52,140

OK.



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00:05:52,340 --> 00:06:00,850

Public stream the return type of this method is strange and the name of this line if it is our poods



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00:06:01,960 --> 00:06:05,720

some values to the screen.



95

00:06:06,390 --> 00:06:08,490

Ok for example.



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00:06:08,890 --> 00:06:15,490

And then I put up around brackets after my method name and then I open and close my method by using



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00:06:15,490 --> 00:06:16,950

these curly braces.



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00:06:16,960 --> 00:06:22,040

So inside the Smurfette I want to actually put my own implementations inside the Smurfette.



99

00:06:22,050 --> 00:06:22,460

OK.



100

00:06:22,600 --> 00:06:27,980

So here I can just type in return and then I can just put these two double quotes here.



101

00:06:28,210 --> 00:06:32,240

So as you can see here we need to actually return a value of types three in here.



102

00:06:32,260 --> 00:06:35,860

Ok this may affect the return type of the Smif it is string.



103

00:06:36,040 --> 00:06:44,650

So return and as against the inside of double quotes I can just type in name colon and then plus operator



104

00:06:44,890 --> 00:06:51,070

and then I want to actually to access the name instance variable that is declared inside this Animal



105

00:06:51,070 --> 00:06:51,360

class.



106

00:06:51,370 --> 00:06:51,850

OK.



107

00:06:52,000 --> 00:06:58,900

So as you know this math class here is actually inheriting all of the features and behaviors that are



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00:06:58,900 --> 00:07:00,250

inside this Animal class.



109

00:07:00,370 --> 00:07:06,450

So you can actually access the instance variables that are inside this animal class.



110

00:07:06,700 --> 00:07:14,830

But because this instance variables are declared as private I cannot see this instance variables these



111

00:07:15,130 --> 00:07:18,630

instance variables are still part of this chat class.



112

00:07:18,670 --> 00:07:20,670

OK but I cannot see them.



113

00:07:20,820 --> 00:07:21,480

OK.



114

00:07:21,580 --> 00:07:29,140

When you declare your instance variables or your methods as private data class that contains all those



115

00:07:29,140 --> 00:07:34,480

private parts has complete control over those private parts of that class.



116

00:07:34,480 --> 00:07:34,940

OK.



117

00:07:35,080 --> 00:07:42,080

So this animal class actually has complete control over these private instance variables and this cat



118

00:07:42,080 --> 00:07:48,190

class can not see those are private parts that are inside this Animal class.



119

00:07:48,190 --> 00:07:54,040

So here in this chat class inside this output some values to the screen Meffert.



120

00:07:54,250 --> 00:07:58,560

You want to actually access the value of the name instance variable.



121

00:07:58,600 --> 00:08:00,650

I can just typing get a name.



122

00:08:00,730 --> 00:08:08,530

OK so are I assure you that you can actually use our diskettes name in order to access the value of



123

00:08:08,530 --> 00:08:10,050

the named instance variable.



124

00:08:10,210 --> 00:08:17,080

But there is another way that we can actually access those private parts of that class.



125

00:08:17,080 --> 00:08:17,550

OK.



126

00:08:17,710 --> 00:08:23,860

So as you can see here this Animal class in this Animal class these are the private parts we have and



127

00:08:23,860 --> 00:08:27,030

other our access modifier called Protector's.



128

00:08:27,150 --> 00:08:32,430

OK protected this protected access modifier is just like private's.



129

00:08:32,500 --> 00:08:40,720

It actually allows the subclasses of this superclass this animal class to access these private parts



130

00:08:40,810 --> 00:08:43,200

that are inside of this animal class.



131

00:08:43,360 --> 00:08:44,040

OK.



132

00:08:44,260 --> 00:08:51,520

So inside this cat class I can just refer to the name instance variable that is declared inside this



133

00:08:51,610 --> 00:08:56,440

animal class because I use this protected access modifier.



134

00:08:56,500 --> 00:09:03,580

So this access modifier actually allows us actually allows other classes that are subclasses of this



135

00:09:04,030 --> 00:09:08,200

animal class to access these instance variables.



136

00:09:08,200 --> 00:09:08,710

OK.



137

00:09:08,770 --> 00:09:11,990

Only subclasses can access this instance variable.



138

00:09:12,160 --> 00:09:19,660

Ok the cat class is actually related to this animal class so I can actually access this named instance



139

00:09:19,660 --> 00:09:25,540

variable OK because we are inheriting all of the features and behaviors that are inside these Animal



140

00:09:25,540 --> 00:09:26,120

class.



141

00:09:26,140 --> 00:09:26,750

OK.



142

00:09:27,010 --> 00:09:33,660

So let's actually change the access modifier of Ds are instance variables to protected.



143

00:09:33,670 --> 00:09:35,780

And here I can just take and protected.



144

00:09:36,070 --> 00:09:38,300

And here again just like in Protector's.



145

00:09:38,680 --> 00:09:39,500

OK.



146

00:09:39,880 --> 00:09:41,950

And then inside is chat's class as you can see.



147

00:09:41,950 --> 00:09:46,360

Now I can actually access those instance variables directly.



148

00:09:46,360 --> 00:09:46,910

OK.



149

00:09:47,260 --> 00:09:53,810

But this is not the proper way to allow other classes to access your instance variables.



150

00:09:53,950 --> 00:09:54,400

OK.



151

00:09:54,490 --> 00:10:02,490

Always allow the other classes to access the value of your variables by using those getters and setters.



152

00:10:02,520 --> 00:10:02,960

OK.