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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


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