Constructor - Basic Java Programming

constructor is a spacial member function of class. member function name and class name should be same is called constructor. it execute when object is initialize for that class.


Eg:

class A
{
void A()
{
System.out.println("constructor called");
}
public static void main(String[] args)
{
A a=new A();
}
}

output:
constructor called

From the above Java code contains one class named as "A".then the class have two member functions one is "A()" and another one is "main()".Now the Member Function name and class name should be same its called as constructor.We initialize the object for class A inside the main method.then the constructor automatically executed.

Types Of Constructor

1.Simple Constructor

2. Parameterized Constructor

Simple Contractor

The Constructor Does Not Pass Parameters.

Parameterized Constructor

The Constructor Pass Parameters.

eg:

class A

{

void A(int a)

{

System.out.println("Parameterized Constructor : "+a);

}

public static void main(String[] args)

{

A a=new A();

a(20);

}

}

Constructor Overloading
Same Constructor Name With Different Set Of Parameters.