Skip to main content

Inheritance-4

Example10:-


class Student
{
Student()
{
System.out.println("This is super class Zero argument constructor");
}
Student(String s)
{
System.out.println("This is super class One argument constructor");
}
}
class Test extends Student
{
Test()
{
super(null);
System.out.println("This is sub class Zero argument constructor");
}
public static void main(String[]args)
{
Test t=new Test();
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test

This is super class One argument constructor
This is sub class Zero argument constructor

Example11:-


class Student
{
Student()
{
System.out.println("This is super class Zero argument constructor");
}
Student(String s)
{
System.out.println("This is super class One argument constructor");
}
}
class Test extends Student
{
Test()
{
super();
super(null);
System.out.println("This is sub class Zero argument constructor");
}
public static void main(String[]args)
{
Test t=new Test();
}
}

Output:-

C:\JAVATECH>javac Test.java

Test.java:17: error: call to super must be first statement in constructor
super(null);
     ^
1 error


Example12:-


class Student
{
Student()
{
System.out.println("This is super class Zero argument constructor");
}
Student(String s)
{
System.out.println("This is super class One argument constructor");
}
}
class Test extends Student
{
Test()
{
System.out.println("This is sub class Zero argument constructor");
}
Test(String s)
{
System.out.println("This is sub class One argument constructor");
}
public static void main(String[]args)
{
Test t1=new Test();
Test t2=new Test(null);
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test

This is super class Zero argument constructor
This is sub class Zero argument constructor
This is super class Zero argument constructor
This is sub class One argument constructor


Example:-13


class Student
{
Student()
{
System.out.println("This is super class Zero argument constructor");
}
Student(String s)
{
System.out.println("This is super class One argument constructor");
}
}
class Test extends Student
{
Test()
{
super(null);
System.out.println("This is sub class Zero argument constructor");
}
Test(String s)
{
super(null);
System.out.println("This is sub class One argument constructor");
}
public static void main(String[]args)
{
Test t1=new Test();
Test t2=new Test(null);
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test

This is super class One argument constructor
This is sub class Zero argument constructor
This is super class One argument constructor
This is sub class One argument constructor


Multilevel inheritance: - Multilevel inheritance is a collection of single inheritance or collection of more single inheritance.

class A{}
class B extends A{}
class C extends B{}
or
class A{}
class B extends A{}
class C extends B{}
class D extends C{}


Example14:-


class A
{
void A()
{
System.out.println("A class Method");
}
}
class B extends A
{
void B()
{
System.out.println("B class Method");
}
}
class C extends B
{
void C()
{
System.out.println("C class Method");
}
}
class Test
{
public static void main(String[]args)
{
C object=new C();
object.A();
object.B();
object.C();
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test

A class Method
B class Method
C class Method


Example15:-


class A
{
int a;
}
class B extends A
{
int b;
}
class C extends B
{
void setData()
{
a=10;
b=100;
}
void getData()
{
System.out.println("sum="+(a+b));
}
}
class Test
{
public static void main(String[]args)
{
C object=new C();
object.setData();
object.getData();
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test

sum=110



Comments

Popular posts from this blog

inheritance

INHERITANCE:- Inheritance is the process of code re-usability, using this property software or applications can develop in less time or can develop rapidly. Inheritance increases the readability of code and decrease redundancy or repetition of code or reduces size of code. Use of previously developed code in future any number of times is called inheritance. Through inheritance variables and methods of class can inherited. Types of Inheritance:- 1)         Single or Single level inheritance 2)         Multilevel inheritance 3)         Hierarchical inheritance Java does not support to multiple inheritance. Single or single level inheritance:- In a single inheritance a class is inherited by a single class. In a single or single level inheritance a sub class having only one super class directly or indirectly. Syntax: -        class Subclass ex...

Abstraction,Encapsulation And Inheritance

Abstraction  is a one of the great feature of Oops,in this feature hide entire details of product, show only requirement specifications(what product will do). The main purpose behind abstraction is to increase productivity or use of product without knowledge of product implementation. in this case the person don't know how product  was implemented but know how product works or action of product. In java abstraction is achieved by abstract class and interface,here interface provide 100% abstraction and abstract class provide partial abstraction. For example: - ATM machine is example of abstraction.  every technical and non-technical person use facility of ATM without knowing the entire process. they know if they click on withdraw button then they can withdraw money from ATM machine but they don't know when they click on withdraw button the request is send to the server and after go into database and so on. Here ATM machine show only requirement specificat...