Difference between revisions of "Java/C2/First-Java-Program/English-timed"

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|-
 
|-
 
|  00:09
 
|  00:09
|| In this tutorial we will learn  
+
|| In this tutorial, we will learn:
  
 
|-
 
|-
 
|  00:11
 
|  00:11
| To create a simple Java program.  
+
|* To create a simple Java program   
  
 
|-
 
|-
 
|  00:14
 
|  00:14
| To compile the program.
+
|* To compile the program  
  
 
|-
 
|-
 
|  00:16
 
|  00:16
| To run the programand
+
|* To run the program and
  
 
|-
 
|-
 
|  00:19
 
|  00:19
| About the naming conventions followed in Java
+
|* About the naming conventions followed in Java.
  
 
|-
 
|-
 
|  00:23
 
|  00:23
|  Here we are using '''Ubuntu version 11.10''' and '''jdk 1.6'''
+
|  Here we are using '''Ubuntu version 11.10''' and '''jdk 1.6'''.
  
 
|-
 
|-
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|-
 
|-
 
|  00:39
 
|  00:39
|If not, for relevant tutorial please visit our website which is as shown.
+
|If not, for relevant tutorial, please visit our website which is as shown.
  
 
|-
 
|-
 
|  00:46
 
|  00:46
|Alright now let us   write our first Java program.
+
|Alright now let us write our first Java program.
  
 
|-
 
|-
 
|  00:51
 
|  00:51
|For that you need a '''Terminal''' and you need  a '''Text''' '''Editor'''.
+
|For that, you need a '''Terminal''' and you need  a '''Text Editor'''.
  
 
|-
 
|-
 
|  00:56
 
|  00:56
| I am using '''gedit''' as my '''Text Editor'''  
+
| I am using '''gedit''' as my '''Text Editor'''.
  
 
|-
 
|-
 
|01:01
 
|01:01
|  In the '''text editor'''   , we will first create the class '''HelloWorld'''.  
+
|  In the '''text editor''', we will first create the '''class''' '''HelloWorld'''.  
  
 
|-
 
|-
 
|  01:06
 
|  01:06
|So type class '''HelloWorld'''. '''HelloWorld '''is the name of the class.
+
|So type: class '''HelloWorld'''. "HelloWorld" is the name of the '''class'''.
  
 
|-
 
|-
 
|  01:17
 
|  01:17
| And   Open '''curly bracket'''.  '''Enter''' and close '''curly bracket'''.
+
| And open '''curly bracket'''.  '''Enter''' and close '''curly bracket'''.
  
 
|-
 
|-
 
|  01:24
 
|  01:24
|  The code between this two curly brackets  will belong to the class '''HelloWorld'''
+
|  The code between these two curly brackets  will belong to the '''class''' 'HelloWorld'.
  
 
|-
 
|-
 
|  01:33
 
|  01:33
|  Now save the file by clicking on '''Save '''icon at the top  
+
|  Now save the file by clicking on '''Save''' icon at the top.
  
 
|-
 
|-
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|-
 
|-
 
|  01:51
 
|  01:51
|  Here, in the home directory i will create a folder.
+
|  Here, in the '''home directory''' I will create a folder.
  
 
|-
 
|-
 
|  01:57  
 
|  01:57  
|Let us name it   '''Demo''' and press ''' enter'''
+
|Let us name it '''Demo''' and press '''Enter'''.
 
|-
 
|-
 
|  02:02
 
|  02:02
|Then inside this folder we will save the file.
+
|Then, inside this folder we will save the file.
  
 
|-
 
|-
 
|  02:08
 
|  02:08
| In the '''Name''' text-box, type the name of the class.
+
| In the '''Name''' text-box, type the name of the '''class'''.
  
 
|-
 
|-
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|-
 
|-
 
|  02:20
 
|  02:20
|Recall that we  created  class   HelloWorld.
+
|Recall that we  created  '''class HelloWorld'''.
  
 
|-
 
|-
 
|  02:25
 
|  02:25
|So we will save the file   as''' HelloWorld dot java'''
+
|So, we will save the file as ''' HelloWorld dot java'''.
  
 
|-
 
|-
 
| 02:33
 
| 02:33
|  '''Dot''' Java is the file extension  given to the Java file.
+
|  '''Dot Java''' (.java) is the file extension  given to the Java file.
  
 
|-
 
|-
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|-
 
|-
 
|  02:47
 
|  02:47
| Inside the class, we write the '''main''' method.  
+
| Inside the '''class''', we write the '''main method'''.  
  
 
|-
 
|-
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|-
 
|-
 
|  02:54
 
|  02:54
|'''''public static void main '''  ''parentheses'' inside  ''parentheses'' '''String''' '''arg''' Square brackets''  
+
|'''public static void main'''  parentheses inside  parentheses '''String''' '''arg''' square brackets''  
  
 
|-
 
|-
 
|  03:10
 
|  03:10
|'''Main''' functions marks the starting point of the program.
+
|'''main''' function marks the starting point of the program.
  
 
|-
 
|-
 
|  03:15
 
|  03:15
|We will describe '''public, static, void and String ''' in a future tutorial.
+
|We will describe '''public, static, void and String '''in a future tutorial.
  
 
|-
 
|-
 
|  03:23
 
|  03:23
|Then  once again, open curly bracket.
+
|Then  once again, open curly bracket,
  
 
|-
 
|-
 
|  03:27
 
|  03:27
|Press '''Enter '''and close curly bracket.
+
|press '''Enter '''and close curly bracket.
 
    
 
    
 
|-
 
|-
 
|  03:32
 
|  03:32
|  The code between these two curly brackets will belong to the main method.
+
|  The code between these two curly brackets will belong to the '''main method'''.
  
 
|-
 
|-
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|-
 
|-
 
|  03:46
 
|  03:46
|So inside main method  type'''''System '''dot''' out '''dot''' println''''' parentheses semi-colon
+
|So, inside '''main''' '''method''', type: '''System dot out dot println''' parentheses semi-colon.
  
 
|-
 
|-
 
|  03:59
 
|  03:59
|This is the statement used to print a line.    
+
|This is the statement used to print a line,    
  
 
|-
 
|-
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|-
 
|-
 
|  04:10
 
|  04:10
|Now let us tell Java, what to print.
+
|Now let us tell Java, what to print.
  
 
|-
 
|-
 
|  04:13
 
|  04:13
| So Within '''parentheses in double quotes type, My first java program exclamation mark'''.
+
| So, within parentheses in double quotes, type: '''My first Java program''' exclamation mark.
  
 
|-
 
|-
 
|  04:30
 
|  04:30
|  Let us '''Save'''the file by clicking on '''Save''' icon.
+
|  Let us save the file by clicking on '''Save''' icon.
  
 
|-
 
|-
 
|  04:36
 
|  04:36
|  Let's go   to '''Terminal'''.
+
|  Let's go to the '''Terminal'''.
  
 
|-
 
|-
 
|  04:38
 
|  04:38
|Make sure that you are in the directory where  you save your  '''HelloWorld.java'''  
+
|Make sure that you are in the directory where  you saved your  'HelloWorld.java'  
  
 
|-
 
|-
 
|  04:46
 
|  04:46
|Remember that I am in my home directory.
+
|Remember that I am in my '''home''' directory.
  
 
|-
 
|-
 
|  04:50
 
|  04:50
|So''''' '''''type''''' cd '''Space''' Demo '''''and''''' '''hit''' Enter'''''
+
|So, type: '''cd''' Space '''Demo ''' and hit '''Enter'''.
  
 
|-
 
|-
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|-
 
|-
 
|  04:59
 
|  04:59
|We see  ''' HelloWorld.java''' file present in the Demo folder.
+
|We see  'HelloWorld.java' file present in the Demo folder.
  
 
|-
 
|-
 
|  05:06
 
|  05:06
| Lets compile this file so type   '''javac '''Space''' HelloWorld '''dot''' java''''' and hit''' enter'''  
+
| Let's compile this file. So, type: '''javac''' Space ''' HelloWorld''' dot '''java''' and hit '''Enter'''.
  
 
|-
 
|-
 
|  05:21
 
|  05:21
|This   compile the file that we have created.  
+
|This compiles the file that we have created.  
  
 
|-
 
|-
 
| 05:25
 
| 05:25
|  Alright now the file is compiled as we see no error.
+
|  Alright, now the file is compiled as we see no error.
  
 
|-
 
|-
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|-
 
|-
 
|  05:38
 
|  05:38
|That is, on any '''Operating System. '''
+
|That is, on any '''Operating System.'''
  
 
|-
 
|-
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|-
 
|-
 
|  05:51
 
|  05:51
| So After successful compilation, run the program using the command,  
+
| So, after successful compilation, run the program using the command,  
  
 
|-
 
|-
 
|  05:56
 
|  05:56
|'''''java '''''(This time no c) space '''''HelloWorld '''''(and no dot java extension) and hit '''Enter'''.
+
|'''java'''(This time no c) space '''HelloWorld'''(and no dot java extension) and hit '''Enter'''.
  
 
|-
 
|-
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|-
 
|-
 
|  08:48
 
|  08:48
|  For    Example: showString(), main(), goToHelp(). Here '''s''' of show is in lowercase while  '''S''' of string is in uppercase  
+
|  For    Example: showString(), main(), goToHelp(). Here '''s''' of show is in lowercase while  '''S''' of string is in uppercase.
  
 
|-
 
|-
 
|09:02
 
|09:02
|The variable name should not begin with '''digits''' .  
+
|The variable name should not begin with '''digits'''.  
  
 
|-
 
|-
 
|  09:06
 
|  09:06
| We cannot use keywords for our '''class, method or variable name'''.
+
| We cannot use keywords for our '''class, method''' or '''variable name'''.
 
|-
 
|-
 
|  09:13
 
|  09:13
|For example:  cannot use keywords like''' public, private, void, static and many more'''.  
+
|For example:  cannot use keywords like '''public, private, void, static''' and many more.  
  
 
|-
 
|-
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|-
 
|-
 
|09:35
 
|09:35
|For self assessment write a simple java program to print '''Java file name and class name should be same'''.
+
|For self assessment, write a simple java program to print "Java file name and class name should be same".
  
 
|-
 
|-
 
|  09:47
 
|  09:47
|To know more about the Spoken Tutorial Project
+
|To know more about the Spoken Tutorial Project,
  
 
|-
 
|-
 
|  09:50
 
|  09:50
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]  
 
|-
 
|-
 
|  09:58
 
|  09:58
| It summarises the Spoken Tutorial project  
+
| It summarizes the Spoken Tutorial project.
  
 
|-
 
|-
 
|  10:02
 
|  10:02
| 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.
  
 
|-
 
|-
 
| 10:08
 
| 10:08
|  The Spoken Tutorial Project Team
+
|  The Spoken Tutorial Project team:
  
 
|-
 
|-
 
|  10:10
 
|  10:10
| Conducts workshops using spoken tutorials  
+
| Conducts workshops using spoken tutorials.
  
 
|-
 
|-
 
|  10:13
 
|  10:13
|Gives certificates to those who pass an online test  
+
|Gives certificates to those who pass an online test.
  
 
|-
 
|-
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|-
 
|-
 
| 10:25
 
| 10:25
|  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.
  
 
|-
 
|-
 
|  10:30
 
|  10:30
|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.
  
 
|-
 
|-
 
|  10:38
 
|  10:38
| 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]  
+
  
 
|-
 
|-
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|-
 
|-
 
| 10:53  
 
| 10:53  
|This is Prathamesh Salunke signing off.  Jai Hind.  
+
|This is Prathamesh Salunke, signing off.  Jai Hind.  
  
 
|}
 
|}

Revision as of 11:38, 18 March 2015

Time Narration
00:02 Welcome to the Spoken Tutorial on getting started with the First java program.
00:09 In this tutorial, we will learn:
00:11 * To create a simple Java program
00:14 * To compile the program
00:16 * To run the program and
00:19 * About the naming conventions followed in Java.
00:23 Here we are using Ubuntu version 11.10 and jdk 1.6.
00:32 To follow this tutorial JDK 1.6 must be installed on your system.
00:39 If not, for relevant tutorial, please visit our website which is as shown.
00:46 Alright now let us write our first Java program.
00:51 For that, you need a Terminal and you need a Text Editor.
00:56 I am using gedit as my Text Editor.
01:01 In the text editor, we will first create the class HelloWorld.
01:06 So type: class HelloWorld. "HelloWorld" is the name of the class.
01:17 And open curly bracket. Enter and close curly bracket.
01:24 The code between these two curly brackets will belong to the class 'HelloWorld'.
01:33 Now save the file by clicking on Save icon at the top.
01:37 It is a good practice to save the file frequently.
01:43 so Save As Dialog box appears.
01:46 Browse the location where you want to save your file.
01:51 Here, in the home directory I will create a folder.
01:57 Let us name it Demo and press Enter.
02:02 Then, inside this folder we will save the file.
02:08 In the Name text-box, type the name of the class.
02:13 In Java, the name of the class and the file name should be same.
02:20 Recall that we created class HelloWorld.
02:25 So, we will save the file as HelloWorld dot java.
02:33 Dot Java (.java) is the file extension given to the Java file.
02:39 Then click on Save button. So the file is now saved.
02:47 Inside the class, we write the main method.
02:53 So type:
02:54 public static void main parentheses inside parentheses String arg square brackets
03:10 main function marks the starting point of the program.
03:15 We will describe public, static, void and String in a future tutorial.
03:23 Then once again, open curly bracket,
03:27 press Enter and close curly bracket.
03:32 The code between these two curly brackets will belong to the main method.
03:41 We will now write a code to display a line on the Terminal.
03:46 So, inside main method, type: System dot out dot println parentheses semi-colon.
03:59 This is the statement used to print a line,
04:05 semi-colon is used to terminate a line.
04:10 Now let us tell Java, what to print.
04:13 So, within parentheses in double quotes, type: My first Java program exclamation mark.
04:30 Let us save the file by clicking on Save icon.
04:36 Let's go to the Terminal.
04:38 Make sure that you are in the directory where you saved your 'HelloWorld.java'
04:46 Remember that I am in my home directory.
04:50 So, type: cd Space Demo and hit Enter.
04:56 ls, press Enter.
04:59 We see 'HelloWorld.java' file present in the Demo folder.
05:06 Let's compile this file. So, type: javac Space HelloWorld dot java and hit Enter.
05:21 This compiles the file that we have created.
05:25 Alright, now the file is compiled as we see no error.
05:30 We can see HelloWorld.class file created.
05:36 This file can run anywhere.
05:38 That is, on any Operating System.
05:41 We do not need java compiler as well.
05:45 Hence, java is rightly described as “write once, run anywhere.”
05:51 So, after successful compilation, run the program using the command,
05:56 java(This time no c) space HelloWorld(and no dot java extension) and hit Enter.
06:07 You will get the output My first java program!
06:13 So we have written our first java program.Let us go back to editor
06:22 Now, remove the semi-colon which is at the end of the statement.
06:27 Click on Save icon.
06:29 Let us go back to the Terminal.
06:33 Run the command javac HelloWorlddot java.
06:41 The compiler gives an error.
06:44 It says, a semi colon is expected on the fifth line.
06:52 The up arrow points to the error statement.
06:57 Let us go back to the Editor.
07:01 In Java, all statements are terminated with semicolons.
07:06 So go to the fifth line and add a semicolon.
07:13 Click on the Save icon. It is necessary to save the file before compiling
07:22 Let us go back to the Terminal.
07:25 Compile the file using javac Hello World dot java.
07:32 The file is successfully compiled as we see no errors.
07:36 Now, run the program using the command java HelloWorld and .
07:45 We see the output My first java program!
07:49 This is how you handle errors in java.
07:54 As the series progresses, we will learn more about the errors.
08:02 We now see what are the naming conventions in java.
08:06 * The class name should be in CamelCase.
08:10 * Which means each new word begins with an upper case.
08:14 * Example: class HelloWorld, class ChessGame.
08:19 So, H of Hello and W of World are in uppercase.
08:25 Similarly C and G of ChessGame respectively are in uppercase.
08:31 The method name should be the mixed case.
08:35 Which means that the first word should begin with a lower case.
08:39 And all new words followed should begin with an upper case.
08:44 Also the method name should be a verb.
08:48 For Example: showString(), main(), goToHelp(). Here s of show is in lowercase while S of string is in uppercase.
09:02 The variable name should not begin with digits.
09:06 We cannot use keywords for our class, method or variable name.
09:13 For example: cannot use keywords like public, private, void, static and many more.
09:22 So in this tutorial, we have learnt to write, compile and run a simple java program.
09:30 We also saw the naming conventions followed in java.
09:35 For self assessment, write a simple java program to print "Java file name and class name should be same".
09:47 To know more about the Spoken Tutorial Project,
09:50 watch the video available at [1]
09:58 It summarizes the Spoken Tutorial project.
10:02 If you do not have good bandwidth, you can download and watch it.
10:08 The Spoken Tutorial Project team:
10:10 Conducts workshops using spoken tutorials.
10:13 Gives certificates to those who pass an online test.
10:17 For more details, please write to contact@spoken-tutorial.org
10:25 Spoken Tutorial Project is a part of the Talk to a Teacher project.
10:30 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
10:38 More information on this mission is available at:

[2]

10:49 We have come to the end of this tutorial.
10:51 Thanks for joining.
10:53 This is Prathamesh Salunke, signing off. Jai Hind.