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

From Script | Spoken-Tutorial
Jump to: navigation, search
 
(2 intermediate revisions by 2 users not shown)
Line 6: Line 6:
  
 
|-
 
|-
| 00:03
+
| 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
+
| 00:10
| what is '''constructor overloading'''
+
| what is '''constructor overloading'''
  
 
|-
 
|-
| 00:13
+
| 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'''.
  
Line 42: Line 42:
  
 
|-
 
|-
| 00:40
+
| 00:40
 
| What is '''constructor overloading'''?
 
| What is '''constructor overloading'''?
  
Line 160: Line 160:
 
|  03:47
 
|  03:47
 
|  This time we see no error, since we have defined 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();'''.
  
 
|-
 
|-
Line 206: Line 207:
 
|-
 
|-
 
|  04:58
 
|  04:58
| Let's 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."
  
 
|-
 
|-
Line 227: Line 224:
 
| 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
Line 244: Line 242:
  
 
|-
 
|-
| 06:22
+
| 06:22
| Let us call the '''method'''.
+
|Let us call the '''method'''.
  
 
|-
 
|-
Line 276: Line 274:
  
 
|-
 
|-
|   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.
  
Line 289: Line 287:
 
|-
 
|-
 
| 07:16
 
| 07:16
| within curly brackets '''roll_number '''is equal to '''num'''.
+
| within curly brackets '''roll_number '''is equal to '''num'''.
  
 
|-
 
|-
Line 312: Line 310:
  
 
|-
 
|-
| 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.'''
  
Line 328: 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].   
+
|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].
+
  
 
|-
 
|-
| 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