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Constructor-2

Applicable access modifiers for constructor.

Example1:- Single constructor with private modifier.

class Student
{
private Student()
{
System.out.println("This is private constructor");
}
public static void main(String[]args)
{
Student s1=new Student(); 
}
}

Output:-
 C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student

This is private constructor

Example2:- Single constructor with public modifier but more object created.

class Student
{
public Student()
{
System.out.println("This is public constructor");
}
public static void main(String[]args)
{
Student s1=new Student(); 
Student s2=new Student(); 
Student s3=new Student(); 
}
}

Output:-
C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student

This is public constructor
This is public constructor
This is public constructor


Example3:- Single constructor with protected modifier but more object created.

class Student
{
static int i=0;
protected Student()
{
i++;
System.out.println(i+" Object created in protected Constructor");
}
public static void main(String[]args)
{
Student s1=new Student();
Student s2=new Student();
Student s3=new Student();
}
}

Output:-
C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student

1 Object created  in protected Constructor
2 Object created  in protected Constructor
3 Object created  in protected Constructor


Example4:-Multiple Constructor-1.

class Student
{

private Student()
{
System.out.println("Zero argument private Constructor");
}
protected Student(int a)
{
System.out.println("Parameterized protected Constructor");
}
public static void main(String[]args)
{
Student s1=new Student();
Student s2=new Student(10);
}
}

Output:-

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

Zero argument private Constructor
Parameterized protected Constructor

Example5:-Multiple Constructor-2.

class Student
{

public Student()
{
System.out.println("Zero argument public Constructor");
}
private Student(int a)
{
System.out.println("Parameterised  private Constructor");
}
protected Student(Student t)
{
System.out.println("Parameterised protected Copy Constructor");
}
public static void main(String[]args)
{
Student s1=new Student();
Student s2=new Student(10);
Student s3=new Student(s2);
}
}

Output:-

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

Zero argument public Constructor
Parameterised private Constructor

Parameterised protected Copy Constructor


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