abstract class
- We can create abstract class by using abstract keyword.
- A class which is declared as abstract is known as abstract class.
- abstract class can contains,
- constructor
- variables
- abstract methods
- non abstract methods
- sub class
- abstract methods will be implemented in sub class of abstract class.
- If sub class didn't provide the implementation for abstract method then we need to declare that sub class as abstract class.
- If any class extends this sub class then that sub class will provide the implementation for abstract methods.
- object creation is not possible for abstract class.
abstract class NameOfTheAbstractClass
{
It can contains variables, abstract or non abstract methods;
}
Fun point
Nagi : Hari, in abstract class we learn implemented and unimplemented methods,
Fun point
Nagi : Hari, in abstract class we learn implemented and unimplemented methods,
- Do we have concepts like,
- implemented and unimplemented variables?
- implemented and unimplemented constructors ?
- implemented and unimplemented blocks ?
- Both we will sit and develop these things and ll the keep name as Bisket coding language.
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Program : abstract class
Program name : Test1.java
Output :
This is method1
This is method2
abstract class Demo1
{
public void method1()
{
System.out.println("This is method1");
}
public abstract void method2();
}
class Demo2 extends Demo1
{
public void method2()
{
System.out.println("This is method2");
}
}
class Test1
{
public static void main(String args[])
{
Demo2 demo2 = new Demo2();
demo2.method1();
demo2.method2();
}
}
Compile : javac Test1.java
Run : java Test1
Output :
This is method1
This is method2
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Program : abstract class
Program name : Test2.java
Output :
This is method1
This is method2
This is method3
This is method1
This is method2
This is method3
abstract class Demo1
{
public void method1()
{
System.out.println("This is method1");
}
public abstract void method2();
public abstract void method3();
}
abstract class Demo2 extends Demo1
{
public void method2()
{
System.out.println("This is method2");
}
}
class Demo3 extends Demo2
{
public void method3()
{
System.out.println("This is method3");
}
}
class Test2
{
public static void main(String args[])
{
Demo3 demo3 = new Demo3();
demo3.method1();
demo3.method2();
demo3.method3();
demo3.method3();
}
}
Compile : javac Test2.java
Run : java Test2
Output :
This is method1
This is method2
This is method3
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This is method3
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Thanks for your time.
Nireekshan