Difference between revisions of "Java/C2/Instance-fields/English-timed"

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|-
 
|-
−
| 00:02
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| 00:02
 
| Welcome to the Spoken Tutorial on '''Instance fields''' in '''Java'''.
 
| Welcome to the Spoken Tutorial on '''Instance fields''' in '''Java'''.
  
 
|-
 
|-
 
| 00:06
 
| 00:06
−
| In this tutorial, we will learn  
+
| In this tutorial, we will learn:
  
 
|-
 
|-
−
| 00:08
+
|00:08
−
|   About '''instance fields'''
+
|About '''instance fields'''
  
 
|-
 
|-
−
| 00:10
+
|00:10
−
|   To access the '''instance fields '''of a '''class'''
+
|To access the '''instance fields''' of a '''class'''
  
 
|-
 
|-
−
| 00:13
+
|00:13
−
| '''Modifiers''' for '''instance fields'''
+
|'''Modifiers''' for '''instance fields'''
 +
 
 
|-
 
|-
−
| 00:15
+
|00:15
−
| And Why '''instance fields''' are called so?
+
|And, why '''instance fields''' are called so?
  
 
|-
 
|-
−
| 00:18
+
| 00:18
−
| Here we are using  
+
| Here we are using:
  
 
|-
 
|-
−
| 00:20
+
|00:20
−
|   Ubuntu version 11.10  
+
|'''Ubuntu version 11.10'''
 +
 
 
|-
 
|-
−
| 00:22
+
|00:22
−
|     jdk 1.6
+
|'''jdk 1.6'''
 +
 
 
|-
 
|-
−
| 00:24
+
|00:24
−
| And  Eclipse IDE 3.7.0
+
|And  '''Eclipse IDE 3.7.0'''
  
 
|-
 
|-
−
|   00:27
+
| 00:27
−
| To follow this tutorial you must know  
+
| To follow this tutorial, you must know  
  
 
|-
 
|-
 
| 00:30
 
| 00:30
−
| how to create a '''class '''in '''Java '''using '''Eclipse'''.
+
| how to create a '''class '''in '''Java''' using '''Eclipse'''.
  
 
|-
 
|-
 
| 00:33
 
| 00:33
−
| You must also know how to create an '''object '''for the '''class'''.
+
| You must also know how to create an '''object '''for the '''class'''.
  
 
|-
 
|-
 
| 00:38
 
| 00:38
−
| If not, for relevant tutorials please visit our website which is as shown,
+
| If not, for relevant tutorials, please visit our website which is as shown.
−
 
+
http://www.spoken-tutorial.org  
−
('''http'''://'''www.spoken'''-'''tutorial.org''')
+
  
 
|-
 
|-
 
| 00:43
 
| 00:43
−
| We know that objects store their individual states in''' fields'''.
+
| We know that objects store their individual states in''' fields'''.
  
 
|-
 
|-
 
| 00:48
 
| 00:48
−
| These fields are declared without the  '''static'''  keyword.
+
| These fields are declared without the  '''static'''  keyword.
  
 
|-
 
|-
 
| 00:51
 
| 00:51
−
| We will learn about''' static fields''' in the coming tutorials.
+
| We will learn about''' static fields''' in the coming tutorials.
  
 
|-
 
|-
 
| 00:55
 
| 00:55
−
| '''Non-static fields''' are also known as '''''instance variables '''''or''''' instance fields.'''''
+
| '''Non-static fields''' are also known as '''instance variables '''or''' instance fields.'''
  
 
|-
 
|-
−
| 01:01
+
| 01:01
−
|   Let us go back to the '''Student class''' we had already created.
+
| Let us go back to the '''Student class''' we had already created.
  
 
|-
 
|-
 
| 01:09
 
| 01:09
−
| We can see that here''' roll_no''' and '''name''' are the '''instance fields''' of this '''class'''.
+
| We can see that here''' roll_no''' and '''name''' are the '''instance fields''' of this '''class'''.
  
 
|-
 
|-
 
| 01:15
 
| 01:15
−
| Now, we will learn how to access these '''fields'''.
+
| Now, we will learn how to access these '''fields'''.
  
 
|-
 
|-
−
| 01:18
+
| 01:18
−
| For that, let us open the '''TestStudent class '''which we had already created.
+
| For that, let us open the '''TestStudent class '''which we had already created.
  
 
|-
 
|-
 
| 01:27
 
| 01:27
−
| We can remove the statement for creating the second '''object'''.
+
| We can remove the statement for creating the second '''object'''.
  
 
|-
 
|-
 
| 01:33
 
| 01:33
−
| We will also remove the '''println '''statements.
+
| We will also remove the '''println '''statements.
  
 
|-
 
|-
 
| 01:41
 
| 01:41
−
| Now we will access the fields '''roll_no''' and '''name'''  of the student class using'''stud1 '''and the''' dot operator'''.
+
| Now we will access the '''fields''', '''roll_no''' and '''name''', of the student class using '''stud1 '''and the ''dot operator''.
  
 
|-
 
|-
 
| 01:49
 
| 01:49
−
| So for that  type '''System''' ''dot'' '''out''' ''dot'' '''println''' within brackets and double quotes, '''The roll number is''', then ''plus '''''stud1''''' dot ''''' from the option provided select''''' roll_no''''' '' press '''Enter'''  then ''semicolon''.  
+
| So, for that, type: '''System''' dot '''out''' dot '''println''' within brackets and double quotes '''The roll number is''' then plus '''stud1''' dot from the option provided select ' roll_no' press '''Enter'''  then semicolon.  
  
 
|-
 
|-
 
| 02:15
 
| 02:15
−
|  Next line type '''System''' ''dot'' '''out''' ''dot'' '''println''' within brackets and double quotes '''The name is''',  ''plus '''''stud1''''' dot select '''''name'''''  press '''enter''' ''  then ''semicolon''.
+
|  Next line, type: '''System''' dot '''out''' dot '''println''' within brackets and double quotes '''The name is''' plus '''stud1''' dot select 'name' press '''Enter''' then semicolon.
  
 
|-
 
|-
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|-
 
|-
 
| 02:48
 
| 02:48
−
|  We get the output as  
+
|  We get the output as:
  
 
|-
 
|-
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|-
 
|-
 
| 03:09
 
| 03:09
−
|  After the '''memory''' is allocated for the '''object''' the '''fields''' are initialized to '''null '''or '''zero'''.
+
|  After the '''memory''' is allocated for the '''object''', the '''fields''' are initialized to '''null '''or '''zero'''.
  
 
|-
 
|-
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|-
 
|-
 
| 03:27
 
| 03:27
−
|So type,'''int ''' ''' roll_no''' equal to '''50'''  next line string  '''name''' equal to within double quotes '''Raju'''.
+
|So, type: '''int ''' ''' roll_no''' equal to '''50'''  next line '''String''' '''name''' equal to within double quotes '''Raju'''.
  
 
|-
 
|-
 
| 03:42
 
| 03:42
−
| | Now, '''save '''and '''run '''the file. Press '''Ctrl,S''' and '''Ctrl F11 '''
+
| | Now, '''save '''and '''run '''the file. Press '''Ctrl, S''' and '''Ctrl, F11'''.
  
 
|-
 
|-
 
| 03:50
 
| 03:50
−
|  We get the '''output''' as expected '''The roll number is 50'''.  
+
|  We get the output as expected; '''The roll number is 50'''.  
  
 
|-
 
|-
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|-
 
|-
 
|  03:56  
 
|  03:56  
−
|This is because we have explicitly initialize the variables  in the '''Student''' class
+
|This is because we have explicitly initialized the variables  in the '''Student''' '''class'''.
  
 
|-
 
|-
 
| 04:04
 
| 04:04
−
|  We can see that here the '''fields '''have no '''modifier '''or''' '''the''' default modifier'''.
+
|  We can see that here the '''fields '''have no '''modifier '''or ''' default modifier'''.
  
 
|-
 
|-
 
| 04:10
 
| 04:10
−
|  Recall '''modifiers''' we had discussed in '''Creating Classes.'''
+
|  Recall '''modifiers''', we had discussed in '''Creating Classes.'''
  
 
|-
 
|-
Line 184: Line 186:
 
|-
 
|-
 
| 04:22
 
| 04:22
−
|  We can see that here they are in the same '''default package'''.
+
|  We can see that, here, they are in the same '''default package'''.
  
 
|-
 
|-
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|-
 
|-
 
| 04:34
 
| 04:34
−
| We will now change the modifier to '''private'''.
+
| We will now change the '''modifier''' to '''private'''.
  
 
|-
 
|-
 
| 04:37  
 
| 04:37  
−
|  So before the '''field''' declarations type '''private'''. So type '''private int ''' '''roll no=50'''.
+
|  So, before the '''field''' declarations, type: '''private'''. So, type: '''private''' space '''int roll_no=50;'''.
  
 
|-
 
|-
 
| 04:48
 
| 04:48
−
|  Next line '''private string''' '''name ='''Raju'''.
+
|  Next line, '''private''' space '''String''' '''name = Raju;'''.
  
 
|-
 
|-
 
| 04:53
 
| 04:53
−
| Now '''save''' the file '''Student.java'''.
+
| Now '''save''' the file '''Student.java'''.
  
 
|-
 
|-
−
| 05:00
+
| 05:00
−
| | We can see that we get errors in '''TestStudent.java'''.
+
| We can see that we get errors in '''TestStudent.java'''.
  
 
|-
 
|-
 
| 05:05
 
| 05:05
−
| Hover the mouse over the error symbol.
+
| Hover the mouse over the error symbol.
  
 
|-
 
|-
 
| 05:08
 
| 05:08
−
| It says '''The field Student '''''dot '''''roll ''''' '''''number '''is not visible.
+
| It says '''The field Student ''' dot '''roll number '''is not visible.
−
 
+
  
 
|-
 
|-
 
| 05:12
 
| 05:12
−
| And '''The field Student '''''dot '''''name '''is not visible.
+
| And '''The field Student ''' dot '''name '''is not visible.
  
 
|-
 
|-
 
| 05:16
 
| 05:16
−
| This is because private fields can be accessed only within its own class.
+
| This is because '''private fields''' can be accessed only within its own class.
  
 
|-
 
|-
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|-
 
|-
−
| 05:52
+
| 05:52
−
| Now  '''Save''' the file and '''Run''' the program
+
| Now  '''Save''' the file and '''Run''' the program.
  
 
|-
 
|-
 
| 06:00
 
| 06:00
−
|  We see the '''output''' on the console. The '''Roll no is 50'''   the name is '''Raju'''.
+
|  We see the output on the console. '''The Roll no is 50''' '''The name is Raju'''.
  
 
|-
 
|-
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|-
 
|-
 
| 06:22  
 
| 06:22  
−
|  '''Instance fields''' are called so because their values are unique to each '''''instance''''' of a class.
+
|  '''Instance fields''' are called so because their values are unique to each '''instance''' of a class.
  
 
|-
 
|-
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|-
 
|-
 
|  06:34
 
|  06:34
−
|  Let us go to the '''TestStudent class'''.
+
|  Let us go back to the '''TestStudent class'''.
  
 
|-
 
|-
 
| 06:43
 
| 06:43
−
| Here, we will create one more object of the '''Student class'''.
+
| Here, we will create one more object of the '''Student class'''.
  
 
|-
 
|-
 
| 06:50
 
| 06:50
−
| So type next line'''Student''' space '''stud2''' equal to '''new''' space '''Student''' , opening and closing brackets semicolon.
+
| So, type: next line, '''Student''' space '''stud2''' equal to '''new''' space '''Student''' opening and closing brackets semicolon.
  
 
|-
 
|-
 
| 07:06
 
| 07:06
−
|  We will now initialize both the objects in the'''TestStudent class'''.
+
|  We will now initialize both the objects in the '''TestStudent class'''.
  
 
|-
 
|-
 
| 07:18
 
| 07:18
−
|  Next line type '''stud1''' ''dot '' select'''roll_no'''  press ''' enter''' equal to '''20 '''  ''semicolon.''
+
|  So, next line, type: '''stud1''' dot select '''roll_no'''  press ''' Enter''' equal to '''20 ''' semicolon.  
  
 
|-
 
|-
 
| 07:32
 
| 07:32
−
|  Next line type '''stud1''' ''dot'' select  '''name''' press '''enter''' equal to within double quotes '''Ramu '''''semicolon'' press '''enter'''.
+
|  Next line, type: '''stud1''' dot select  '''name''' press '''Enter''' equal to within double quotes '''Ramu ''' semicolon press '''Enter'''.
  
 
|-
 
|-
 
| 07:54
 
| 07:54
−
|  Thus we have initialized the fields for the first object.
+
|  Thus we have initialized the '''fields''' for the first object.
  
 
|-
 
|-
 
| 07:58
 
| 07:58
−
|  Now, we will initialize the fields for the second object.
+
|  Now, we will initialize the '''fields''' for the second object.
  
 
|-
 
|-
 
| 08:02
 
| 08:02
−
|  So type '''stud2''' ''dot'' select'''roll_no''' equal to '''30 '''  ''semicolon''.
+
|  So, type: '''stud2''' dot select '''roll_no''' equal to '''30 '''semicolon.
  
 
|-
 
|-
 
|08:15  
 
|08:15  
−
| Next line   '''stud2''' ''dot'' select '''name''' equal to within double quotes''' Shyamu '''''semicolon'''''  press''' enter'''.
+
| Next line, '''stud2''' dot select '''name''' equal to within double quotes''' Shyamu ''' semicolon''' press''' Enter'''.
  
 
|-
 
|-
 
| 08:34
 
| 08:34
−
| Now after the '''println''' statements, type '''System''' '''dot''' '''out''' dot '''println''' within brackets and double quotes '''The roll number is''',  ''plus '''''stud2 '''''dot select '''''roll_no''''' ''and  ''semicolon''.  
+
| Now, after the '''println''' statements, type: '''System''' dot '''out''' dot '''println''' within brackets and double quotes '''The roll number is''' plus '''stud2 ''' dot select '''roll_no''' and  semicolon.  
  
 
|-
 
|-
 
| 09:03
 
| 09:03
−
| '''System''' ''dot'' '''out''' ''dot'' '''println''' within brackets and double quotes '''The name is''', ''plus '''''stud2 '''''dot select '''''name''''' ''and   ''semicolon''.
+
| '''System''' dot '''out''' dot '''println''' within brackets and double quotes '''The name is''', plus '''stud2 ''' dot select '''name''' and semicolon.
  
 
|-
 
|-
 
| 09:28
 
| 09:28
−
|  Now, '''save''' and''' run '''the file. Press ''' Ctrl,s''' and '''Ctrl, F11'''   
+
|  Now, '''save''' and''' run '''the file. Press ''' Ctrl, s''' and '''Ctrl, F11'''.  
  
 
|-
 
|-
 
| 09:38
 
| 09:38
−
|   We get the output as follows.  The roll_no is '''20'', The name is''' Ramu''' roll_no is '''30''',   name is''' shyamu'''.
+
| We get the output as follows.  '''The roll_no is 20''', '''The name is Ramu''' '''The roll_no is 30''', '''The name is shyamu'''.
  
 
|-
 
|-
 
| 09:47
 
| 09:47
−
|  Here both '''stud1''' and '''stud2''' are referring to two different '''objects'''.
+
|  Here, both '''stud1''' and '''stud2''' are referring to two different '''objects'''.
  
 
|-
 
|-
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|-
 
|-
 
| 09:56
 
| 09:56
−
|  We can see that here.
+
|  We can see that here.The first object has the values '''20''' and '''Ramu'''.
−
 
+
−
|-
+
−
| 09:57
+
−
|  The first object has the values '''20''' and '''Ramu'''.
+
  
 
|-
 
|-
 
| 10:02
 
| 10:02
−
|  The second object has the values '''30 '''and '''Shyamu''' .
+
|  The second object has the values '''30 '''and '''Shyamu'''.
  
 
|-
 
|-
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|-
 
|-
 
| 10:36
 
| 10:36
−
|  We will now, print the values  of the third '''object'''  
+
|  We will now print the values  of the third '''object'''.
  
 
|-
 
|-
 
| 10:44
 
| 10:44
−
| So type '''System''' ''dot'' '''out''' ''dot'' '''println''' within brackets and double quotes '''The  roll_no is''',  ''plus '''''stud3 '''''dot select '''''roll_no'''''    ''semicolon''.
+
| So, type: '''System''' dot '''out''' dot '''println''' within brackets and double quotes '''The  roll_no is''' plus '''stud3 ''' dot select '''roll_no''' semicolon.
  
 
|-
 
|-
 
| 11:09
 
| 11:09
−
|next line type  '''System''' ''dot'' '''out''' ''dot'' '''println''' within brackets and double quotes '''The  name is''',  ''plus '''''stud3 '''''dot   ''''' name'''''    ''semicolon''.
+
|next line, type: '''System''' dot '''out''' dot '''println''' within brackets and double quotes '''The  name is''' plus '''stud3 ''' dot''' name''' semicolon.
 +
 
 
|-
 
|-
 
| 11:29
 
| 11:29
Line 368: Line 366:
 
|-
 
|-
 
|  11:46
 
|  11:46
−
|  This is because we had explicitly initialized the fields of the '''Student''' class to''' 50''' and ''' Raju'''.
+
|  This is because we had explicitly initialized the fields of the '''Student class''' to''' 50''' and ''' Raju'''.
  
 
|-
 
|-
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|-
 
|-
−
| 12:02
+
| 12:02
 
| So in this tutorial, we learnt:  
 
| So in this tutorial, we learnt:  
  
 
|-
 
|-
−
| 12:05
+
|12:05
−
|* About instance fields.
+
|About instance fields.
 +
 
 
|-
 
|-
−
| 12:07
+
|12:07
−
|* Accessing the fields using dot operator.
+
|Accessing the fields using dot operator.
  
 
|-
 
|-
−
| 12:11
+
|12:11
−
| | For self assessment,
+
|For self assessment,
  
 
|-
 
|-
−
| 12:13
+
|12:13
−
| Create an  object '''emp2''' in the '''Test Employee''' '''class''' already created.
+
|Create an  object '''emp2''' in the '''TestEmployee''' '''class''' already created.
  
 
|-
 
|-
−
| 12:18
+
|12:18
−
| Then initialize the values of the two objects using dot operator.
+
|Then initialize the values of the two objects using '''dot operator'''.
  
 
|-
 
|-
−
| 12:23
+
|12:23
−
| Use 55 and Priya as values for first object.
+
|Use '''55''' and '''Priya''' as values for first object.
  
 
|-
 
|-
 
| 12:27
 
| 12:27
−
| Use 45 and Sandeep as values for second object.
+
| Use '''45''' and '''Sandeep''' as values for second object.
  
 
|-
 
|-
−
| 12:31
+
|12:31
−
| Display values for both the objects in the output.
+
|Display the values for both the objects in the output.
  
 
|-
 
|-
−
| 12:34
+
|12:34
−
| To know more about the Spoken Tutorial Project,
+
|To know more about the Spoken Tutorial Project,
 +
 
 
|-
 
|-
−
| 12:37
+
|12:37
−
|   watch the video available at [http://spoken-tutorial.org/What_is_a_Spoken_Tutorial]  
+
|watch the video available at [http://spoken-tutorial.org/What_is_a_Spoken_Tutorial].
  
 
|-
 
|-
−
| 12:40
+
|12:40
−
| It summarizes the Spoken Tutorial project.  
+
|It summarizes the Spoken Tutorial project.  
  
 
|-
 
|-
−
| 12:43
+
|12:43
−
|   If you do not have good bandwidth, you can download and watch it.  
+
|If you do not have good bandwidth, you can download and watch it.  
  
 
|-
 
|-
−
|   12:47
+
|12:47
 
| The Spoken Tutorial project team:  
 
| The Spoken Tutorial project team:  
  
Line 433: Line 433:
  
 
|-
 
|-
−
| 12:52
+
| 12:52
−
| Gives certificates for those who pass an online test.  
+
| Gives certificates to those who pass an online test.  
  
 
|-
 
|-
Line 441: Line 441:
  
 
|-
 
|-
−
| 13:01
+
| 13:01
 
| Spoken Tutorial Project is a part of the Talk to a Teacher project.  
 
| Spoken Tutorial Project is a part of the Talk to a Teacher project.  
  
 
|-
 
|-
 
| 13:05
 
| 13:05
−
| It is supported by the National Mission on Education through ICT, MHRD, Government of India.  
+
| It is supported by the National Mission on Education through ICT, MHRD, Government of India.  
  
 
|-
 
|-
 
| 13:11
 
| 13:11
−
|   More information on this mission is available at  
+
| More information on this mission is available at [http://spoken-tutorial.org/NMEICT-Intro].
−
[http://spoken-tutorial.org/NMEICT-Intro]  
+
  
 
|-
 
|-
−
| 13:09
+
| 13:19
−
| Thus we have come to the end of this tutorial.
+
| Thus we have come to the end of this tutorial.
  
 
|-
 
|-
 
| 13:22  
 
| 13:22  
−
| This is Arya Ratish from IIT Bombay, signing off. Thanks for joining.
+
| This is Arya Ratish from IIT Bombay, signing off. Thanks for joining.

Latest revision as of 15:41, 9 March 2017

Time Narration
00:02 Welcome to the Spoken Tutorial on Instance fields in Java.
00:06 In this tutorial, we will learn:
00:08 About instance fields
00:10 To access the instance fields of a class
00:13 Modifiers for instance fields
00:15 And, why instance fields are called so?
00:18 Here we are using:
00:20 Ubuntu version 11.10
00:22 jdk 1.6
00:24 And Eclipse IDE 3.7.0
00:27 To follow this tutorial, you must know
00:30 how to create a class in Java using Eclipse.
00:33 You must also know how to create an object for the class.
00:38 If not, for relevant tutorials, please visit our website which is as shown.

http://www.spoken-tutorial.org

00:43 We know that objects store their individual states in fields.
00:48 These fields are declared without the static keyword.
00:51 We will learn about static fields in the coming tutorials.
00:55 Non-static fields are also known as instance variables or instance fields.
01:01 Let us go back to the Student class we had already created.
01:09 We can see that here roll_no and name are the instance fields of this class.
01:15 Now, we will learn how to access these fields.
01:18 For that, let us open the TestStudent class which we had already created.
01:27 We can remove the statement for creating the second object.
01:33 We will also remove the println statements.
01:41 Now we will access the fields, roll_no and name, of the student class using stud1 and the dot operator.
01:49 So, for that, type: System dot out dot println within brackets and double quotes The roll number is then plus stud1 dot from the option provided select ' roll_no' press Enter then semicolon.
02:15 Next line, type: System dot out dot println within brackets and double quotes The name is plus stud1 dot select 'name' press Enter then semicolon.
02:39 Now, save and run the file TestStudent.java. So press Ctrl, S and Ctrl, F11.
02:48 We get the output as:
02:51 The roll number is 0.
02:53 The name is null.
03:00 This is because, we have not initialized the variables to any value.
03:05 In Java, the fields cannot have random values.
03:09 After the memory is allocated for the object, the fields are initialized to null or zero.
03:15 This work is done by the constructor.
03:18 We will learn about constructor in the coming tutorials.
03:21 Now, we will initialize the fields explicitly and see the output.
03:27 So, type: int roll_no equal to 50 next line String name equal to within double quotes Raju.
03:42 Now, save and run the file. Press Ctrl, S and Ctrl, F11.
03:50 We get the output as expected; The roll number is 50.
03:54 The name is Raju.
03:56 This is because we have explicitly initialized the variables in the Student class.
04:04 We can see that here the fields have no modifier or default modifier.
04:10 Recall modifiers, we had discussed in Creating Classes.
04:14 We can access the fields because both Student.java and TestStudent.java are in the same package.
04:22 We can see that, here, they are in the same default package.
04:30 We will learn about packages in the later tutorials.
04:34 We will now change the modifier to private.
04:37 So, before the field declarations, type: private. So, type: private space int roll_no=50;.
04:48 Next line, private space String name = Raju;.
04:53 Now save the file Student.java.
05:00 We can see that we get errors in TestStudent.java.
05:05 Hover the mouse over the error symbol.
05:08 It says The field Student dot roll number is not visible.
05:12 And The field Student dot name is not visible.
05:16 This is because private fields can be accessed only within its own class.
05:23 You can try accessing roll_no and name from the Student class itself.
05:27 You will find that you can access them without any error.
05:32 Now let us change the modifier to protected.
05:52 Now Save the file and Run the program.
06:00 We see the output on the console. The Roll no is 50 The name is Raju.
06:07 This is because protected fields can be accessed within the same package.
06:17 Now let us see why instance fields are called so?
06:22 Instance fields are called so because their values are unique to each instance of a class.
06:29 In other words each object of a class will have unique values.
06:34 Let us go back to the TestStudent class.
06:43 Here, we will create one more object of the Student class.
06:50 So, type: next line, Student space stud2 equal to new space Student opening and closing brackets semicolon.
07:06 We will now initialize both the objects in the TestStudent class.
07:18 So, next line, type: stud1 dot select roll_no press Enter equal to 20 semicolon.
07:32 Next line, type: stud1 dot select name press Enter equal to within double quotes Ramu semicolon press Enter.
07:54 Thus we have initialized the fields for the first object.
07:58 Now, we will initialize the fields for the second object.
08:02 So, type: stud2 dot select roll_no equal to 30 semicolon.
08:15 Next line, stud2 dot select name equal to within double quotes Shyamu semicolon press Enter.
08:34 Now, after the println statements, type: System dot out dot println within brackets and double quotes The roll number is plus stud2 dot select roll_no and semicolon.
09:03 System dot out dot println within brackets and double quotes The name is, plus stud2 dot select name and semicolon.
09:28 Now, save and run the file. Press Ctrl, s and Ctrl, F11.
09:38 We get the output as follows. The roll_no is 20, The name is Ramu The roll_no is 30, The name is shyamu.
09:47 Here, both stud1 and stud2 are referring to two different objects.
09:52 This means that the two objects have unique values.
09:56 We can see that here.The first object has the values 20 and Ramu.
10:02 The second object has the values 30 and Shyamu.
10:09 Now, let us create one more object.
10:13 So type Student space stud3 equal to new space Student within brackets opening and closing brackets semicolon.
10:36 We will now print the values of the third object.
10:44 So, type: System dot out dot println within brackets and double quotes The roll_no is plus stud3 dot select roll_no semicolon.
11:09 next line, type: System dot out dot println within brackets and double quotes The name is plus stud3 dot name semicolon.
11:29 Now, save and run the file. So press Ctrl, S and Ctrl, F11 .
11:36 We can see that the third object contains the values 50 and Raju.
11:46 This is because we had explicitly initialized the fields of the Student class to 50 and Raju.
11:54 Now, try de-initializing the fields and see the output for the third object.
12:02 So in this tutorial, we learnt:
12:05 About instance fields.
12:07 Accessing the fields using dot operator.
12:11 For self assessment,
12:13 Create an object emp2 in the TestEmployee class already created.
12:18 Then initialize the values of the two objects using dot operator.
12:23 Use 55 and Priya as values for first object.
12:27 Use 45 and Sandeep as values for second object.
12:31 Display the values for both the objects in the output.
12:34 To know more about the Spoken Tutorial Project,
12:37 watch the video available at [1].
12:40 It summarizes the Spoken Tutorial project.
12:43 If you do not have good bandwidth, you can download and watch it.
12:47 The Spoken Tutorial project team:
12:49 Conducts workshops using spoken tutorials.
12:52 Gives certificates to those who pass an online test.
12:56 For more details, please write to contact@spoken-tutorial.org
13:01 Spoken Tutorial Project is a part of the Talk to a Teacher project.
13:05 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
13:11 More information on this mission is available at [2].
13:19 Thus we have come to the end of this tutorial.
13:22 This is Arya Ratish from IIT Bombay, signing off. Thanks for joining.

Contributors and Content Editors

Arya Ratish, Gaurav, PoojaMoolya, Sandhya.np14, Sneha

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