Abstract read at class
When you defining a class,You actually defining new data type through that the object can be created for additional requirements.New class can be defined by the word “class” .Inside the class you’ll be able to define different variables and method having property of accessibility.
In java when we aren’t specifying access property it’s by default as public.So that outside that class ,object can access class property easily.
Syntax for defining category
class class_name
You can say that class is the combination of methods and instance variable.If you wish to define a class named “box” then you’ll be able to define it like this
class box
Inside it you’ll be able to simply defines its variable and methods.
Sample of class
Closer look at objects
As we’ve got mentioned that once you create a class it usually creating one data type through which the object of specific data type are often defined.In easy words objects are instance of class ,Lets have a glance syntax to declare objects
Syntax to declare objects
Class_name object_name=new class_name();
This is the direct way through that you’ll be able to simply create object using new operator.Suppose we’ve got class named box that we’ve got used above.Then we are able to create object like this
box obj=new box();
To access the variable named width of box class then we can do it by
obj.width;
Consider that when you are creating a class then you’re assigning all the property to that specific object’s memory location.It may be interesting when you will execute your first java program having oop concept of class-object.
Problem–Execute a java program having class-object idea
Code–
class box{
int width;
int height;
int depth;
}
class boxdemo{
public static void main(String args[])
{
box obj=new box();
obj.width=10;
obj.height=20;
obj.depth=30;
int volume;
volume=(obj.width*obj.height*obj.depth);
System.out.println(“Volume of box= “+volume);
}
}
Output
Volume of box=6000
We have simply accessed all variable of box category and then calculated volume of that box using object.If you’ve got any question relating to this subject then contact us or mention it in comment box!