Java/C2/Creating-class/English-timed

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Time Narration
00:02 Welcome to the spoken tutorial on Creating classes.
00:05 In this tutorial, we will learn about:
00:08 A class in real world
00:10 A class in Java
00:12 Structure of a Java class
00:14 Syntax for a Java class
00:16 And a simple example of Java class.
00:19 Here we are using: Ubuntu version 11.10, JDK 1.6 and Eclipse 3.7.0
00:30 To follow this tutorial, you must know how to write, compile and run a simple Java program in Eclipse.
00:37 If not, please see the spoken-tutorial on these topics, available at spoken-tutorial.org.
00:46 Now let us see what is a class in real world.
00:50 Whatever we can see in this world are all objects.
00:54 And all the objects can be categorized into special groups.
00:59 Each group is termed as a class.
01:02 For example, human being is a class.
01:05 We are all different objects of this class.
01:08 We all have different properties like eyes, legs, hands etc.
01:13 which are common to the 'human being' class.
01:15 Seeing, eating, walking etc are behaviors that are common to the human being class.
01:22 Now let us see what is the class in Java?
01:26 A class is the blueprint from which individual objects are created.
01:31 Structure of a Java Class; A class defines:
01:35 A set of properties called variables .
01:37 And a set of behaviors called methods.
01:40 Now, let us see the syntax for declaring classes.
01:44 modifier – class -classname within curly brackets variable, constructor and method declarations.
01:52 We will learn about these in detail, in the coming tutorials.
01:58 Now, let us create a simple class using Eclipse.
02:03 I have already opened Eclipse.
02:09 Now let us create a Project.
02:11 So click on File, go to New and click on Java Project.
02:20 In the New Project Wizard, enter the Project name as ClassDemo with C and D in capital.
02:34 Then click on Finish.
02:38 We see that the Project ClassDemo is created.
02:43 We will now create a Java class named Student.
02:47 So, right click on ClassDemo, go to New and click on Class.
02:56 In the New Java Class wizard, type the Name as Student.
03:03 We can see that the modifier here is public.
03:07 This shows that the class is visible to all the classes everywhere.
03:11 If a class has no modifier which is the default, it is visible only within its own package.
03:18 We will learn about packages in the later tutorials.
03:23 Here I have selected public.
03:26 In the 'method stubs', select public static void main.
03:31 Then click on Finish.
03:36 We can see that the class named Student is created.
03:40 Now, let me remove the comments.
03:51 A Student class can contain properties like Name, Roll Number, Marks etc.
03:57 So, inside this class Student, let me declare two variables roll_Number and name.
04:04 So, I will type int roll underscore number semicolon.
04:14 String name semicolon.
04:19 So, I have declared two variables.
04:22 Now, a class also contains methods.
04:25 So, let me create a method named StudentDetail.
04:30 This method will give the details of each student.
04:34 So let me type, void studentDetail then opening and closing brackets, curly brackets open.
04:49 Now, this method will give the roll_number and name of the Student.
04:53 So, type System dot out dot println within brackets and double quotes The roll number is we can type it as number is, close the double quotes plus roll_number semicolon.
05:23 Next line, type: System dot out dot println within brackets and double quotes The name is plus name and semicolon.
05:40 Now, inside the main method, we will type: System dot out dot println within brackets and double quotes We have created a class with 2 variables and 1 method.
06:10 Thus, We have created the class student.
06:20 Now, let me save the file by pressing Control and S keys simultaneously.
06:26 Let me Run the program by pressing Control and F11 keys simultaneously.
06:33 We get the output as :We have created a class with 2 variables and 1 method,
06:38 just as we had typed in the main method.
06:46 Thus we have successfully created a class.
06:50 So, in this tutorial, we learnt about the class in java and how to create a class in java.
06:59 For self assessment, create a class named Employee with variables emp underscore number and emp underscore name .
07:10 And method printEmployee which displays the employee information.
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07:48 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
07:55 More information on this mission is available at [2].
08:04 Thus, we come to the end of this tutorial.
08:07 This is Arya Ratish from IIT Bomaby, signing off. Thanks for joining us.

Contributors and Content Editors

Gaurav, PoojaMoolya, Sandhya.np14, Sneha