Skip to main content

Abstract class-2

Example7:-Test.java

abstract class Student
{
abstract void disp();
}
class Test extends Student
{
void disp()
{
System.out.println("Implemented abstract method");
}
public static void main(String[]args)
{
Test t=new Test();
t.disp();
System.out.println("Well-Come Friends");
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test
Implemented abstract method
Well-Come Friends

Example8:-Test.java

abstract class Student
{
public abstract void disp();
}
class Test extends Student
{
void disp()
{
System.out.println("Implemented abstract method");
}
public static void main(String[]args)
{
Test t=new Test();
t.disp();
System.out.println("Well-Come Friends");
}
}

Output:-

C:\JAVATECH>javac Test.java
Test.java:7: error: disp() in Test cannot override disp() in Student
void disp()
     ^
  attempting to assign weaker access privileges; was public
1 error

Example9:-

abstract class Student
{
public abstract void disp();
}
class Test extends Student
{
public void disp()
{
System.out.println("public to public Implemented abstract method");
}
public static void main(String[]args)
{
Test t=new Test();
t.disp();
System.out.println("Well-Come Friends");
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test
Public to public Implemented abstract method
Well-Come Friends

Example10:-

abstract class Student
{
abstract void disp();
}
class Test extends Student
{
public void disp()
{
System.out.println("Default to public Implemented abstract method");
}
public static void main(String[]args)
{
Test t=new Test();
t.disp();
System.out.println("Well-Come Friends");
}
}

Output:-

C:\JAVATECH>javac Test.java
C:\JAVATECH>java Test
Default to public Implemented abstract method
Well-Come Friends


Example11:-

abstract class Student
{
abstract void disp();
abstract void set();
abstract void get();
}
class Test extends Student
{
public void disp()
{
System.out.println(" Implemented abstract disp method");
}
public void set()
{
System.out.println(" Implemented abstract set method");
}
public void get()
{
System.out.println(" Implemented abstract get method");
}
public static void main(String[]args)
{
Test t=new Test();
System.out.println("Well-Come Friends on Demo of Abstract class");
t.disp();
t.set();
t.get();
}
}

Output:-

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

Well-Come Friends on Demo of Abstract class
 Implemented abstract disp method
 Implemented abstract set method
 Implemented abstract get method

Example12:-TestMain.java

abstract class Student
{
abstract void disp();
abstract void set();
abstract void get();
}
class Test extends Student
{
public void disp()
{
System.out.println(" Implemented abstract disp method");
}
public void set()
{
System.out.println(" Implemented abstract set method");
}
}
class TestMain
{
public void get()
{
System.out.println(" Implemented abstract get method");
}
public static void main(String[]args)
{
TestMain t=new TestMain();
System.out.println("Well-Come Friends on Demo of Abstract class");
t.disp();
t.set();
t.get();
}
}

Output:-

C:\JAVATECH>javac Test.java
Test.java:7: error: Test is not abstract and does not override abstract method get() in Student
class Test extends Student
^
1 error

Example13:-TestMain.java

abstract class Student
{
abstract void disp();
abstract void set();
abstract void get();
}
abstract class Test extends Student
{
public void disp()
{
System.out.println(" Implemented abstract disp method");
}
public void set()
{
System.out.println(" Implemented abstract set method");
}
}
class TestMain extends Test
{
public void get()
{
System.out.println(" Implemented abstract get method");
}
public static void main(String[]args)
{
TestMain t=new TestMain();
System.out.println("Well-Come Friends on Demo of Abstract class");
t.disp();
t.set();
t.get();
}
}

Output:-

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

Well-Come Friends on Demo of Abstract class
 Implemented abstract disp method
 Implemented abstract set method
 Implemented abstract get method


Comments

Post a Comment

Popular posts from this blog

Inner classes

Inner Classes:- class inside class or interface called inner class or nested class. Advantage of inner classes is grouping multiple classes and interfaces into a single class. Another big advantage of inner class is that inner class can happily access all the data or variables of outer class directly. Types of Nested classes:- There are two types of nested classes static and non-static nested classes. (A)Non –static inner classes:- 1)     Member inner class 2)     Anonymous inner class 3)     Local inner class (B)Static nested class Example1:-Outer.java class Outer { class Inner { void disp() { System.out.println("Hello This is Inner class Method"); } } public static void main(String[]args) { Inner in=new Inner(); in.disp(); } } Output:- C:\JAVATECH>javac Outer.java Outer.java:12: error: non-static variable this cannot be referenced from a static context Inner in=new Inner(); ...
Post a Comment
Read more

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 su...
Post a Comment
Read more

Small concept about OOPs

Some small concept about OOPs:- In many books and website write about OOPs concepts as hundred percent object oriented, pure object oriented and partial object oriented language. Hundred percent object oriented:- In the hundred percent object oriented movie hero is object, without object program is incomplete that means can not execute program without object. Without class and object programming or application development is not possible. Example of hundred percent object oriented language is  Smalltalk . Pure object oriented:- In the object oriented cinema obviously object is the hero. In pure object oriented language object having same importance but in this having some relax that is without creating object we can successfully execute our application. So in the object oriented programming without class we cannot create or run our application, class is must. Example of pure object oriented language is  Java . Partial object oriented:- In this type of la...
Post a Comment
Read more