Difference between revisions of "Java/C2/Constructor-overloading/English-timed"

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|-
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| 00:03
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| 00:03
 
| Welcome to the Spoken Tutorial on '''constructor overloading''' in''' java'''.
 
| Welcome to the Spoken Tutorial on '''constructor overloading''' in''' java'''.
  
 
|-
 
|-
−
| 00:08
+
| 00:08
−
|   In this tutorial we will learn  
+
| In this tutorial, we will learn  
  
 
|-
 
|-
−
| 00:10
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| 00:10
−
| what is '''constructor overloading'''
+
| what is '''constructor overloading'''
  
 
|-
 
|-
−
| 00:13
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| 00:13
−
| And to overload '''constructor'''
+
| and to '''overload''' '''constructor'''.
  
 
|-
 
|-
−
| 00:16
+
| 00:16
−
|   Here we are using  
+
| Here we are using:
−
 
+
'''Ubuntu version 11.10 OS'''
−
* Ubuntu version 11.10 OS
+
'''Java Development kit 1.6'''
−
* Java Development kit 1.6
+
'''Eclipse 3.7.0'''  
−
* Eclipse 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 '''constructors''' in '''java''' using '''eclipse'''.
+
| how to create '''constructors''' in java using '''eclipse'''.
  
 
|-
 
|-
 
|  00:34
 
|  00:34
−
| 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''')
 
 
|-
 
|-
−
| 00:40
+
| 00:40
−
| What is constructor overloading?
+
| What is '''constructor overloading'''?
  
 
|-
 
|-
 
|  00:43
 
|  00:43
−
| Define multiple '''constructors''' for a class.
+
| Define '''multiple''' '''constructors''' for a '''class'''.
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
|  00:54
 
|  00:54
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| In '''eclipse''', I have a class '''Student''' with two variables and a method.
+
| In '''eclipse''', I have a '''class''' '''Student''' with two variables and a '''method'''.
  
 
|-
 
|-
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|-
 
|-
 
|  01:07
 
|  01:07
−
| So type, '''''Student '''within''' '''parentheses''' int number '''comma''' String the_name.'''''
+
| So, type: '''Student '''within parentheses''' int number '''comma''' String the_name.'''
  
 
|-
 
|-
 
|  01:26
 
|  01:26
−
|Within curly brackets, type '''roll_number''' is equal to '''number.'''
+
|Within curly brackets, type: '''roll_number''' is equal to '''number.'''
  
 
|-
 
|-
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|-
 
|-
 
|  01:46
 
|  01:46
−
| So we have a '''constructor''' with two parameters.
+
| So, we have a '''constructor''' with two '''parameters'''.
  
 
|-
 
|-
 
|  01:51
 
|  01:51
−
|  let us call this '''constructor'''.
+
|  Let us call this '''constructor'''.
  
 
|-
 
|-
 
|  01:53
 
|  01:53
−
| So in '''main method''' type '''new Student''' parentheses semi colon
+
| So, in '''main method''' type: '''new Student''' parentheses semicolon.
  
 
|-
 
|-
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|-
 
|-
 
|  02:22
 
|  02:22
−
| So we need to   pass '''arguments'''.
+
| So, we need to pass '''arguments'''.
  
 
|-
 
|-
 
|  02:25
 
|  02:25
−
| So within parentheses type '''22''' comma in double quotes '''Ram'''.
+
| So, within parentheses type: 22 comma in double quotes '''Ram'''.
  
 
|-
 
|-
Line 116: Line 115:
 
|-
 
|-
 
|  02:36
 
|  02:36
−
|Let us call the method.
+
|Let us call the '''method'''.
  
 
|-
 
|-
 
|  02:38
 
|  02:38
−
| So before '''new ''' type '''Student s''' is equal to '''new student'''.
+
| So, before '''new ''', type: '''Student s''' is equal to '''new student'''.
 
   
 
   
 
|-
 
|-
 
|  02:45
 
|  02:45
−
| Now using the object '''s''' we will call the method  ''' studentDetail()'''
+
| Now, using the object '''s''' we will call the method  ''' studentDetail()'''.
  
 
|-
 
|-
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|-
 
|-
 
|  02:58
 
|  02:58
−
|  We see the output '''22''' and '''Ram.'''
+
|  We see the output: '''22''' and '''Ram.'''
  
 
|-
 
|-
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|-
 
|-
 
|  03:07
 
|  03:07
−
| So type, '''Student''' parentheses.
+
| So, type: '''Student''' parentheses.
  
 
|-
 
|-
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|-
 
|-
 
|  03:21
 
|  03:21
−
| And ''' name is equal to in double quotes hyphen''' that is no name
+
| And ''' name''' is equal to in double quotes hyphen that is no name.
  
 
|-
 
|-
 
|  03:30
 
|  03:30
−
|  So now we can call the '''constructor''' with no parameters.
+
|  So, now we can call the '''constructor''' with no parameters.
  
 
|-
 
|-
 
|  03:35
 
|  03:35
−
| So type'' '''Student''' '''s1''' is equal to '''new''' '''Student''' parentheses'' semicolon.
+
| So, type: '''Student''' '''s1''' is equal to '''new''' '''Student''' parentheses semicolon.
  
 
|-
 
|-
 
|  03:47
 
|  03:47
−
|  This time we see no error, since we have define a constructor without parameter
+
|  This time we see no error, since we have defined a '''constructor''' without parameter.
 +
 
 
|-
 
|-
−
| 03:55  
+
| 03:55  
−
| Then''''' s1 '''dot''' studentDetail'''''.
+
| Then ''' s1 '''dot''' studentDetail();'''.
  
 
|-
 
|-
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|-
 
|-
 
| 04:04
 
| 04:04
−
| So in  the output  we see '''zero''' and '''dash''' when the '''default''' '''constructor''' is called.
+
| So, in  the output  we see '''zero''' and '''dash''' when the default '''constructor''' is called.
  
 
|-
 
|-
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|-
 
|-
 
|  04:13
 
|  04:13
−
| We have two '''constructor''' with different parameter.
+
| We have two '''constructors''' with different parameters.
  
 
|-
 
|-
 
|  04:17
 
|  04:17
−
| Both the '''constructor''' obviously have same name.
+
| Both the '''constructors''' obviously have same name.
  
 
|-
 
|-
 
|  04:20
 
|  04:20
−
| So depending on the type and number of parameter, the '''constructor''' is called.  
+
| So, depending on the type and number of parameters, the '''constructor''' is called.  
  
 
|-
 
|-
 
| 04:26
 
| 04:26
−
| Let us see the advantage of '''constructor''' overloading.
+
| Let us see the advantage of '''constructor''' '''overloading'''.
  
 
|-
 
|-
 
|  04:30
 
|  04:30
−
| Suppose now call a constructor with two parameters.
+
| Suppose, now we call a constructor with two parameters.
  
 
|-
 
|-
 
|  04:35
 
|  04:35
−
| So type '''Student s3= new Student();'''
+
| So, type: '''Student s3= new Student();'''
  
 
|-
 
|-
 
|  04:51
 
|  04:51
−
| Now within parentheses,  suppose i gave the '''name''' argument first and then the '''roll''' '''number.'''
+
| Now within parentheses,  suppose I gave the '''name''' argument first and then the '''roll_number.'''
  
 
|-
 
|-
 
|  04:58
 
|  04:58
−
| let see what happens.
+
| Let's see what happens.So, in double quotes '''Raju''' comma '''45'''.
−
 
+
−
|-
+
−
|  04:59
+
−
| So in ''double quotes '''Raju''' comma '''45'''''
+
  
 
|-
 
|-
 
|  05:08  
 
|  05:08  
−
|  We see an error which states that the '''constructor student with the parameter  String comma int is undefined.'''
+
|  We see an error which states that "The constructor Student with the parameter  String comma int is undefined."
  
 
|-
 
|-
 
| 05:18
 
| 05:18
−
|  So let us define the constructor.
+
|  So, let us first define the constructor.
  
 
|-
 
|-
 
| 05:22
 
| 05:22
−
| So type '''''Student''' within parentheses '''String''' '''the_name''' comma '''int''' '''r_no'''''
+
| So, type: '''Student''' within parentheses '''String''' '''the_name''' comma '''int''' '''r_no'''.
  
 
|-
 
|-
 
| 05:42
 
| 05:42
−
|So over here first parameter is '''string'' and the second parameter is '''int'''
+
|So, over here first parameter is '''string''' and the second parameter is '''int'''.
 +
 
 
|-
 
|-
 
| 05:52
 
| 05:52
−
|Then Within curly bracket, '''roll_number''' is equal to '''r_no.'''
+
|Then, within curly bracket, '''roll_number''' is equal to '''r_no;'''
  
 
|-
 
|-
 
| 06:05
 
| 06:05
−
| And '''name''' is equal to '''the_name.'''
+
| and '''name''' is equal to '''the_name;'''
  
 
|-
 
|-
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|-
 
|-
−
| 06:22
+
| 06:22
−
| Let us call the method.
+
|Let us call the '''method'''.
  
 
|-
 
|-
 
| 06:24
 
| 06:24
−
| So '''s3''' ''dot'' '''studentDetail.'''
+
| So, '''s3''' dot '''studentDetail();'''
  
 
|-
 
|-
 
|  06:29
 
|  06:29
−
|   '''Save''' the program and '''Run'''   
+
| '''Save''' the program and '''Run'''.  
  
 
|-
 
|-
 
|  06:35
 
|  06:35
−
|So we see the output '''45''' and '''Raju'''   
+
|So, we see the output '''45''' and '''Raju'''.  
  
 
|-
 
|-
 
| 06:40
 
| 06:40
−
| So here we see that when we call the '''constructor'''.
+
| So, here we see that when we call the '''constructor'''  
  
 
|-
 
|-
 
| 06:43
 
| 06:43
−
| We do not have to worry about the parameters that we are passing.
+
| we do not have to worry about the parameters that we are passing.
  
 
|-
 
|-
 
| 06:47
 
| 06:47
−
| This is simply because we have define multiple '''constructor''' with different parameters.
+
| This is simply because we have defined multiple '''constructors''' with different parameters.
  
 
|-
 
|-
 
| 06:54
 
| 06:54
−
| So the proper '''constructor''' is '''overloaded.'''
+
| So, the proper '''constructor''' is '''overloaded.'''
  
 
|-
 
|-
−
|   06:57
+
| 06:57
 
| We can therefore now define  a '''constructor''' which takes only one parameter.
 
| We can therefore now define  a '''constructor''' which takes only one parameter.
  
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|-
 
|-
 
| 07:05
 
| 07:05
−
| So type '''Student''' within parentheses '''int num'''.
+
| So, type: '''Student''' within parentheses '''int num''',
  
 
|-
 
|-
 
| 07:16
 
| 07:16
−
| within curly brackets '''roll_number '''is equalto '''num'''.
+
| within curly brackets '''roll_number '''is equal to '''num'''.
  
 
|-
 
|-
 
| 07:25
 
| 07:25
−
| And '''name''' is equal to   '''no''' '''name'''.
+
| And '''name''' is equal to "no name".
  
 
|-
 
|-
 
| 07:33
 
| 07:33
−
| Now  let us call this  '''constructor'''   
+
| Now, let us call this  '''constructor'''.  
  
 
|-
 
|-
 
| 07:43
 
| 07:43
−
| So type '''Student''' '''s4''' ''is'' ''equalto'' '''new''' '''Student'''  this time we will pass an  single argument. So let us pass '''61'''
+
| So, type: '''Student''' '''s4''' is equal to '''new''' '''Student;'''. This time we will pass a single argument. So, let us pass '''61'''.
  
 
|-
 
|-
 
| 08:04
 
| 08:04
−
| Then '''s4''' dot ''' studentDetail '''
+
| Then '''s4''' dot ''' studentDetail(); '''
  
 
|-
 
|-
 
| 08:10
 
| 08:10
−
|  '''Save''' and '''Run''' the program
+
|  '''Save''' and '''Run''' the program.
  
 
|-
 
|-
−
| 08:14
+
| 08:14
−
| So in the output we see  the '''roll''' '''number''' as '''61''' and '''name''' as '''no''' '''name.'''
+
| So, in the output we see  the '''roll number''' as '''61''' and '''name''' as '''no name.'''
  
 
|-
 
|-
 
| 08:21
 
| 08:21
−
| As we can see, the proper overloaded '''constructor''' is called when new is executed.  
+
| As we can see, the proper overloaded '''constructor''' is called when '''new''' is executed.  
  
 
|-
 
|-
 
| 08:27
 
| 08:27
−
| Based upon the parameters specified the proper '''constructor''' is overloaded.  
+
| Based upon the parameters specified, the proper '''constructor''' is overloaded.  
  
 
|-
 
|-
Line 329: Line 326:
  
 
|-
 
|-
−
| 08:40
+
|08:40
−
|   So in this tutorial, we have learnt  
+
| So, in this tutorial, we have learnt:
  
 
|-
 
|-
 
| 08:42
 
| 08:42
−
| About the  '''constructor overloading.'''
+
|About the  '''constructor overloading'''
 
   
 
   
 
|-
 
|-
 
| 08:45
 
| 08:45
−
|   to overload '''constructor''' and the use of constructor overloading
+
|To overload '''constructor''' and the use of constructor overloading
  
 
|-
 
|-
 
|08:50
 
|08:50
−
| For self assessment, create multiple constructors for class '''Employee'''and   Overload the '''constructor.'''  
+
| For self assessment, create multiple constructors for class '''Employee''' and '''overload''' the '''constructor.'''  
  
 
|-
 
|-
 
| 08:58
 
| 08:58
−
| To know more about the Spoken Tutorial Project
+
| To know more about the Spoken Tutorial project,
  
 
|-
 
|-
 
| 09:00
 
| 09:00
−
| Watch the video available at [http://spoken-tutorial.org/What_is_a_Spoken_Tutorial http://spoken-][http://spoken-tutorial.org/What_is_a_Spoken_Tutorial tutorial.org/What_is_a_Spoken_Tutorial]
+
|watch the video available at [http://spoken-tutorial.org/What_is_a_Spoken_Tutorial].
 +
 
 
|-
 
|-
 
| 09:06
 
| 09:06
−
| It summarizes the Spoken Tutorial project  
+
| It summarizes the Spoken Tutorial project.
  
 
|-
 
|-
 
| 09:09
 
| 09:09
−
| 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.
  
 
|-
 
|-
−
|   09:12
+
| 09:12
−
| The Spoken Tutorial Project Team
+
| The Spoken Tutorial project team:
  
 
|-
 
|-
 
| 09:15
 
| 09:15
−
| Conducts workshops using spoken tutorials  
+
| Conducts workshops using spoken tutorials.
  
 
|-
 
|-
 
| 09:17
 
| 09:17
−
| Gives certificates to those who pass an online test  
+
| Gives certificates to those who pass an online test.
  
 
|-
 
|-
 
| 09:20
 
| 09:20
−
| For more details, please write to contact@spoken-tutorial.org  
+
| For more details, please write to contact@spoken-tutorial.org  
  
 
|-
 
|-
−
| 09:26
+
| 09:26
−
| 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.
  
 
|-
 
|-
 
| 09:30
 
| 09:30
−
| 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.
  
 
|-
 
|-
 
| 09:35
 
| 09:35
−
| 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 http://spoken-tutorial.org/NMEICT-Intro]
+
  
 
|-
 
|-
−
| 09:43
+
| 09:43
−
| This brings us to the end of the tutorial  
+
| This brings us to the end of the tutorial.
 
   
 
   
 
|-
 
|-
 
| 09:46
 
| 09:46
−
| Thanks for joining.
+
| Thanks for joining.This is Prathamesh Salunke, signing off.  Jai Hind.  
−
 
+
−
|-
+
−
| 09:47
+
−
| This is Prathamesh Salunke signing off.  Jai Hind.  
+
  
 
|}
 
|}

Latest revision as of 16:09, 9 March 2017


Time Narration
00:03 Welcome to the Spoken Tutorial on constructor overloading in java.
00:08 In this tutorial, we will learn
00:10 what is constructor overloading
00:13 and to overload constructor.
00:16 Here we are using:

Ubuntu version 11.10 OS Java Development kit 1.6 Eclipse 3.7.0

00:27 To follow this tutorial, you must know
00:30 how to create constructors in java using eclipse.
00:34 If not, for relevant tutorials, please visit our website which is as shown.

http://www.spoken-tutorial.org

00:40 What is constructor overloading?
00:43 Define multiple constructors for a class.
00:46 They must differ in number or types of parameters.
00:50 Let us now see how to overload constructor.
00:54 In eclipse, I have a class Student with two variables and a method.
01:03 Let us first create a parameterized constructor.
01:07 So, type: Student within parentheses int number comma String the_name.
01:26 Within curly brackets, type: roll_number is equal to number.
01:38 And name is equal to the_name
01:46 So, we have a constructor with two parameters.
01:51 Let us call this constructor.
01:53 So, in main method type: new Student parentheses semicolon.
02:03 We see an error, it states that constructor Student is undefined.
02:10 This is simply because we have defined a constructor with two parameters.
02:16 And we are calling a constructor without parameters.
02:22 So, we need to pass arguments.
02:25 So, within parentheses type: 22 comma in double quotes Ram.
02:33 We see that the error is resolved.
02:36 Let us call the method.
02:38 So, before new , type: Student s is equal to new student.
02:45 Now, using the object s we will call the method studentDetail().
02:53 Save the program and Run.
02:58 We see the output: 22 and Ram.
03:03 Now let us define a constructor with no parameter.
03:07 So, type: Student parentheses.
03:12 Within curly brackets roll_number is equal to 0.
03:21 And name is equal to in double quotes hyphen that is no name.
03:30 So, now we can call the constructor with no parameters.
03:35 So, type: Student s1 is equal to new Student parentheses semicolon.
03:47 This time we see no error, since we have defined a constructor without parameter.
03:55 Then s1 dot studentDetail();.
04:01 Save and Run the program.
04:04 So, in the output we see zero and dash when the default constructor is called.
04:11 This is constructor overloading.
04:13 We have two constructors with different parameters.
04:17 Both the constructors obviously have same name.
04:20 So, depending on the type and number of parameters, the constructor is called.
04:26 Let us see the advantage of constructor overloading.
04:30 Suppose, now we call a constructor with two parameters.
04:35 So, type: Student s3= new Student();
04:51 Now within parentheses, suppose I gave the name argument first and then the roll_number.
04:58 Let's see what happens.So, in double quotes Raju comma 45.
05:08 We see an error which states that "The constructor Student with the parameter String comma int is undefined."
05:18 So, let us first define the constructor.
05:22 So, type: Student within parentheses String the_name comma int r_no.
05:42 So, over here first parameter is string and the second parameter is int.
05:52 Then, within curly bracket, roll_number is equal to r_no;
06:05 and name is equal to the_name;
06:15 Save the program.
06:18 Now we see that the error is resolved.
06:22 Let us call the method.
06:24 So, s3 dot studentDetail();
06:29 Save the program and Run.
06:35 So, we see the output 45 and Raju.
06:40 So, here we see that when we call the constructor
06:43 we do not have to worry about the parameters that we are passing.
06:47 This is simply because we have defined multiple constructors with different parameters.
06:54 So, the proper constructor is overloaded.
06:57 We can therefore now define a constructor which takes only one parameter.
07:02 That is roll number.
07:05 So, type: Student within parentheses int num,
07:16 within curly brackets roll_number is equal to num.
07:25 And name is equal to "no name".
07:33 Now, let us call this constructor.
07:43 So, type: Student s4 is equal to new Student;. This time we will pass a single argument. So, let us pass 61.
08:04 Then s4 dot studentDetail();
08:10 Save and Run the program.
08:14 So, in the output we see the roll number as 61 and name as no name.
08:21 As we can see, the proper overloaded constructor is called when new is executed.
08:27 Based upon the parameters specified, the proper constructor is overloaded.
08:33 This is how constructor overloading is done.
08:40 So, in this tutorial, we have learnt:
08:42 About the constructor overloading
08:45 To overload constructor and the use of constructor overloading
08:50 For self assessment, create multiple constructors for class Employee and overload the constructor.
08:58 To know more about the Spoken Tutorial project,
09:00 watch the video available at [1].
09:06 It summarizes the Spoken Tutorial project.
09:09 If you do not have good bandwidth, you can download and watch it.
09:12 The Spoken Tutorial project team:
09:15 Conducts workshops using spoken tutorials.
09:17 Gives certificates to those who pass an online test.
09:20 For more details, please write to contact@spoken-tutorial.org
09:26 Spoken Tutorial Project is a part of the Talk to a Teacher project.
09:30 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
09:35 More information on this mission is available at [2].
09:43 This brings us to the end of the tutorial.
09:46 Thanks for joining.This is Prathamesh Salunke, signing off. Jai Hind.

Contributors and Content Editors

Devisenan, Gaurav, PoojaMoolya, Sandhya.np14, Sneha

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