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Inheritance-3

Example6:-Constructor-1

class Student
{
Student()
{
System.out.println("This is super class Zero argument constructor");
}
}
class Test extends Student
{
Test()
{
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 Zero argument constructor
This is sub class Zero argument constructor

Example7:-

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");
}
public static void main(String[]args)
{
Test t=new Test();
}
}

Output:-

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

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

Above example shows that constructor is not inherited because super class contains two constructors but one argument constructor of super class is not executed. When zero argument constructor of sub class Execute then it gives first priority to zero argument constructor of super class (implicitly call super class default or zero argument class).

Example8:-


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();
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 Zero argument constructor
This is sub class Zero argument constructor


Example9:-


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()
{
new Student(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 Zero argument constructor
This is super class One argument constructor
This is sub class Zero argument constructor


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