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

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|-
 
|-
 
|  03:57
 
|  03:57
|  So what we do is in the method instead of '''int''' we will give '''double'''.
+
|  So, what we do is, in the method instead of '''int''' we will give '''double'''.
  
 
|-
 
|-
 
|  04:06
 
|  04:06
|So replace '''''int'''''by '''''double'''''. Save the file  
+
|So replace '''int''' by '''double''' . '''Save''' the file.
  
 
|-
 
|-
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|-
 
|-
 
|  04:24
 
|  04:24
|So here we can pass an integer arguments as well.
+
|So, here we can pass integer arguments as well.
  
 
|-
 
|-
 
|  04:28
 
|  04:28
| Now  '''Save''' and '''Run''' the program
+
| Now  '''Save''' and '''Run''' the program.
  
 
|-
 
|-
 
|  04:32
 
|  04:32
|  In the output we see the sum of two integers variables,
+
|  In the output, we see the sum of two integer variables  
  
 
|-
 
|-
 
|  04:37
 
|  04:37
|And the sum of two numeric arguments that we passed.
+
|and the sum of two numeric arguments that we passed.
  
 
|-
 
|-
 
| 04:43
 
| 04:43
|  Now we see that both the method performs same operation.
+
|  Now we see that both the methods perform same operation.
  
 
|-
 
|-
 
|  04:50
 
|  04:50
|The difference is that the first method  has no parameter. While the second method has  parameters.
+
|The difference is that the first method  has no parameter while the second method has  parameters.
  
 
|-
 
|-
 
|  05:00
 
|  05:00
|So in such case java provides us with '''method''' '''overloading'''.  
+
|So, in such cases java provides us with '''method''' '''overloading'''.  
  
 
|-
 
|-
 
| 05:05
 
| 05:05
| So what we do is give same name to both the methods.
+
| So, what we do is, give same name to both the methods.
  
 
|-
 
|-
 
|  05:09  
 
|  05:09  
|So replace '''''addTwoNumbers''''' with '''''add'''''  also change here.
+
|So, replace '''addTwoNumbers''' with '''add'''; also change here.
  
 
|-
 
|-
 
|  05:29
 
|  05:29
|  We will define one more method with same opearation.
+
|  We will define one more method with same operation.
  
 
|-
 
|-
 
|  05:33
 
|  05:33
|So type '''''void''' '''add'''.''
+
|So, type: '''void''' '''add'''.
  
 
|-
 
|-
 
|  05:38
 
|  05:38
|And''Within parentheses '''int n1 '''comma '''int n2''' comma '''int n3.'''''
+
|And within parentheses '''int n1 '''comma '''int n2''' comma '''int n3.'''
  
 
|-
 
|-
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|-
 
|-
 
| 05:54
 
| 05:54
| Then Within curly brackets '''System''' dot '''out''' dot''' println'''.''
+
| Then, within curly brackets '''System''' dot '''out''' dot''' println'''.
  
 
|-
 
|-
 
|  06:03
 
|  06:03
|''Within parentheses '''n1''' plus '''n2''' plus '''n3'''.''
+
|Within parentheses '''n1''' plus '''n2''' plus '''n3'''.
  
 
|-
 
|-
 
|  06:11
 
|  06:11
|So this method will give sum of three numbers.
+
|So, this method will give sum of three numbers.
  
 
|-
 
|-
 
|  06:17
 
|  06:17
| let us call this method.
+
| Let us call this '''method'''.
  
 
|-
 
|-
 
|  06:19
 
|  06:19
|So type '''''obj dot add''' '''1''' comma''' 5''' comma '''4'''''
+
|So, type: '''obj''' dot '''add''' '''1''' comma''' 5''' comma '''4'''.
  
 
|-
 
|-
 
| 06:35
 
| 06:35
| ''Save''' and '''Run'''   
+
| '''Save''' and '''Run'''.  
  
 
|-
 
|-
 
| 0639
 
| 0639
| In the output we see the sum of three number i.e'''10'''
+
| In the output, we see the sum of three number i.e '''10'''.
  
 
|-
 
|-
 
|  06:47
 
|  06:47
|So Java compiler overloads the proper method depending on the parameters.
+
|So, Java compiler overloads the proper method depending on the parameters.
  
 
|-
 
|-
 
|  06:52  
 
|  06:52  
|It checks the number and type of parameter passed
+
|It checks the number and type of parameters passed.
  
 
|-
 
|-
 
|  06:57
 
|  06:57
|So as a programmer we dont have worry about the method name.
+
|So, as a programmer we don't have to worry about the '''method''' name.
  
 
|-
 
|-
 
|  07:01
 
|  07:01
|Nor even the type or number of argument we  passed.
+
|Nor even the type or number of arguments we  passed.
  
 
|-
 
|-
 
|  07:05  
 
|  07:05  
|  We can create one more method which append strings.
+
|  We can create one more '''method''' which appends strings.
  
 
|-
 
|-
 
|  07:11
 
|  07:11
|So we will create one more '''overload ''' method
+
|So we will create one more '''overload ''' '''method'''.
 
|-
 
|-
 
|  07:15
 
|  07:15
type '''''void add''''' '''String''' '''s1''' comma '''String''' '''s2'''. ''
+
Type: '''void add''''' '''String''' '''s1''' comma '''String''' '''s2'''.  
  
 
|-
 
|-
 
|  07:29
 
|  07:29
|''Within curly brackets '''System''' dot '''out''' dot '''println'''.''
+
|Within curly brackets '''System''' dot '''out''' dot '''println'''.
  
 
|-
 
|-
 
|  07:41
 
|  07:41
|''Within parentheses '''s1''' plus '''s2'''.''
+
|Within parentheses '''s1''' plus '''s2'''.
  
 
|-
 
|-
 
| 07:45
 
| 07:45
| And we will call  this method.
+
| And we will '''call''' this '''method'''.
  
 
|-
 
|-
 
|  07:50
 
|  07:50
|So type '''''obj''' dot '''add'''.''
+
|So, type: '''obj''' dot '''add'''.
  
 
|-
 
|-
 
|  07:55
 
|  07:55
|''Within parentheses in double quotes '''Hello''' comma in double quotes space '''World'''.''
+
|Within parentheses in double quotes '''Hello''' comma in double quotes space '''World'''.
  
 
|-
 
|-
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|-
 
|-
 
|  08:12
 
|  08:12
|  So in the output we see '''Hello''' space '''World'''.
+
|  So, in the output we see '''Hello''' space '''World'''.
  
 
|-
 
|-
 
|  08:16
 
|  08:16
|So the add method with two string arguments, appends the string.
+
|So, the '''add''' '''method''' with two string arguments, appends the string.
  
 
|-
 
|-
 
| 08:21
 
| 08:21
|  Suppose now we declare add method with return type.
+
|  Suppose now we declare '''add method''' with '''return''' type.
  
 
|-
 
|-
 
|  08:27
 
|  08:27
|So type '''int''' '''add''' parentheses  no  parameter and curly brackets.
+
|So, type: '''int''' '''add''' parentheses  no  parameter and curly brackets.
  
 
|-
 
|-
 
|  08:40
 
|  08:40
|  We get an error  it states that '''duplicate method''' add in type addition
+
|  We get an error. It states that '''duplicate method add''' in type addition.
  
 
|-
 
|-
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|-
 
|-
 
|  08:54
 
|  08:54
|So remember that to overload method the parameters must differ.
+
|So, remember that to '''overload''' a  method, the parameters must differ.
  
 
|-
 
|-
 
|  08:58
 
|  08:58
|Having different return types will not overload the method.
+
|Having different '''return''' types will not '''overload''' the '''method'''.
  
 
|-
 
|-
 
|  09:03
 
|  09:03
|So remove this method  and Save the file.
+
|So, remove this method  and '''Save''' the file.
  
 
|-
 
|-
 
|  09:09
 
|  09:09
|This is how '''method overloading''' is done in '''java'''
+
|This is how '''method overloading''' is done in '''java'''.
  
 
|-
 
|-
 
|  09:16
 
|  09:16
|  So in this tutorial we learnt,
+
|  So, in this tutorial we learnt:
  
 
|-
 
|-
 
|  09:18
 
|  09:18
|About '''method overloading.'''
+
|* About '''method overloading.'''
  
 
|-
 
|-
 
|  09:20
 
|  09:20
|To''' overload method.'''
+
|* To''' overload method.'''
  
 
|-
 
|-
 
|  09:22
 
|  09:22
| And advantage of '''method overloading.'''
+
|* And advantage of '''method overloading.'''
  
 
|-
 
|-
 
|    09:25
 
|    09:25
|For self assessment, create a method subtract that subtracts number
+
|For self assessment: create a '''method subtract''' that subtracts number,
  
 
|-
 
|-
 
|09:31   
 
|09:31   
|Overload it.  
+
|overload it.  
  
 
|-
 
|-
 
| 09:33
 
| 09:33
| To know more about the Spoken Tutorial Project
+
| To know more about the Spoken Tutorial project,
 
|-
 
|-
 
|  09:36
 
|  09:36
| 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]  
 
|-
 
|-
 
|  09:42
 
|  09:42
| It summarizes the Spoken Tutorial project  
+
| It summarizes the Spoken Tutorial project.
  
 
|-
 
|-
 
|  09:45
 
|  09:45
| 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.
  
 
|-
 
|-
 
|  09:48
 
|  09:48
| The Spoken Tutorial Project Team
+
| The Spoken Tutorial project team:
  
 
|-
 
|-
 
|  09:50
 
|  09:50
| Conducts workshops using spoken tutorials  
+
| Conducts workshops using spoken tutorials.
  
 
|-
 
|-
 
|  09:52
 
|  09:52
|Give certificates to those who pass an online test  
+
|Gives certificates to those who pass an online test.
  
 
|-
 
|-
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|-
 
|-
 
|  10:01
 
|  10:01
|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.
  
 
|-
 
|-
 
|  10:05
 
|  10:05
|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.
  
 
|-
 
|-
 
|  10:11
 
|  10:11
| 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]
+
  [http://spoken-tutorial.org/NMEICT-Intro].  
  
 
|-
 
|-
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|-
 
|-
 
| 10:22
 
| 10:22
|This is Prathamesh Salunke signing off.  Jai Hind.  
+
|This is Prathamesh Salunke, signing off.  Jai Hind.  
  
 
|}
 
|}

Revision as of 11:08, 2 April 2015


Time Narration
00:01 Welcome to the Spoken Tutorial on method overloading in java.
00:06 In this tutorial we will learn:
00:08 * What is method overloading.
00:10 * And to overload method.
00:13 Here we are using:
  • Ubuntu version 11.10 OS
  • Java Development kit 1.6
  • And Eclipse 3.7.0
00:24 To follow this tutorial, you must know
00:26 how to create methods and
00:29 to overload constructor in java using eclipse.
00:32 If not, for relevant tutorials, please visit our website which is as shown.

http://www.spoken-tutorial.org

00:39 What is method overloading?
00:42 Define two or more methods with same name within a class.
00:46 They must differ in number or types of parameters.
00:50 These methods are called overloaded methods.
00:54 The process is called method overloading.
00:57 Let us now see how to overload a method.
01:00 In eclipse, I have a class Addition.
01:06 Inside the class, we will declare two integer variables.
01:10 So, type: int a is equal to 10 and int b is equal to 5.
01:19 Let us create a method to add these two integers.
01:23 So, type: void add parentheses.
01:30 Within curly brackets, type: System dot out dot println.
01:40 Inside parentheses a+b.
01:44 So, this method will give us the sum of two integer variables.
01:50 Let us create another method which takes two parameters.
01:55 So, type: void addTwoNumbers.
02:04 Within parentheses int num1 comma int num2.
02:14 Then, within curly brackets System dot out dot println num1 plus num2.
02:35 So, this method will give us the sum of two values that are passed as arguments to this method.
02:44 Let us create an object of the class and call the methods.
02:49 So, in the Main method type: Addition i.e the class name obj is equal to new Addition parentheses semicolon.
03:13 Then Obj.add
03:18 And Obj.addTwonumbers within parentheses.
03:31 we will pass two arguments.
03:33 Suppose if we pass floating point values.
03:37 So, type 2.5 comma and an integer 3.
03:45 We get an error which states that: the method addTwoNumbers int comma int of the class addition is not applicable for the arguments double comma int.
03:57 So, what we do is, in the method instead of int we will give double.
04:06 So replace int by double . Save the file.
04:12 we see that the error is resolved.
04:17 we also know that Java automatically i.e. implicitly coverts int into double.
04:24 So, here we can pass integer arguments as well.
04:28 Now Save and Run the program.
04:32 In the output, we see the sum of two integer variables
04:37 and the sum of two numeric arguments that we passed.
04:43 Now we see that both the methods perform same operation.
04:50 The difference is that the first method has no parameter while the second method has parameters.
05:00 So, in such cases java provides us with method overloading.
05:05 So, what we do is, give same name to both the methods.
05:09 So, replace addTwoNumbers with add; also change here.
05:29 We will define one more method with same operation.
05:33 So, type: void add.
05:38 And within parentheses int n1 comma int n2 comma int n3.
05:51 So we have given three parameters.
05:54 Then, within curly brackets System dot out dot println.
06:03 Within parentheses n1 plus n2 plus n3.
06:11 So, this method will give sum of three numbers.
06:17 Let us call this method.
06:19 So, type: obj dot add 1 comma 5 comma 4.
06:35 Save and Run.
0639 In the output, we see the sum of three number i.e 10.
06:47 So, Java compiler overloads the proper method depending on the parameters.
06:52 It checks the number and type of parameters passed.
06:57 So, as a programmer we don't have to worry about the method name.
07:01 Nor even the type or number of arguments we passed.
07:05 We can create one more method which appends strings.
07:11 So we will create one more overload method.
07:15 Type: void add String s1 comma String s2.
07:29 Within curly brackets System dot out dot println.
07:41 Within parentheses s1 plus s2.
07:45 And we will call this method.
07:50 So, type: obj dot add.
07:55 Within parentheses in double quotes Hello comma in double quotes space World.
08:07 Now Save and Run the program.
08:12 So, in the output we see Hello space World.
08:16 So, the add method with two string arguments, appends the string.
08:21 Suppose now we declare add method with return type.
08:27 So, type: int add parentheses no parameter and curly brackets.
08:40 We get an error. It states that duplicate method add in type addition.
08:48 This is because we have already declared a method add with no parameters.
08:54 So, remember that to overload a method, the parameters must differ.
08:58 Having different return types will not overload the method.
09:03 So, remove this method and Save the file.
09:09 This is how method overloading is done in java.
09:16 So, in this tutorial we learnt:
09:18 * About method overloading.
09:20 * To overload method.
09:22 * And advantage of method overloading.
09:25 For self assessment: create a method subtract that subtracts number,
09:31 overload it.
09:33 To know more about the Spoken Tutorial project,
09:36 watch the video available at [1]
09:42 It summarizes the Spoken Tutorial project.
09:45 If you do not have good bandwidth, you can download and watch it.
09:48 The Spoken Tutorial project team:
09:50 Conducts workshops using spoken tutorials.
09:52 Gives certificates to those who pass an online test.
09:56 For more details, please write to contact@spoken-tutorial.org
10:01 Spoken Tutorial Project is a part of the Talk to a Teacher project.
10:05 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
10:11 More information on this mission is available at
[2]. 
10:19 We have come to the end of this tutorial.
10:21 Thanks for joining.
10:22 This is Prathamesh Salunke, signing off. Jai Hind.

Contributors and Content Editors

Devisenan, Gaurav, Jyotisolanki, PoojaMoolya, Pratik kamble, Sandhya.np14, Sneha