Example 1: Java program to demonstrate the use of constructor
GD.java
class GD
{
    int i=0;
    public GD()
    {
        i=i+1;
        System.out.println(i);
    }
    public static void main(String args[])
    {
        GD g=new GD();
        GD k1=new GD();
        GD k2=new GD();
    }
}
Output
godarda@gd:~$ javac GD.java
godarda@gd:~$ java GD
1
1
1
godarda@gd:~$
Example 2: Java program to demonstrate the use of constructor
GD.java
class GD
{
    int a=20;
    GD(int a)
    {
        a=a;
        System.out.println(a);
    }
    public static void main(String args[])
    {
        GD g=new GD(10);
    }
}
Output
godarda@gd:~$ javac GD.java
godarda@gd:~$ java GD
10
godarda@gd:~$
Example 3: Java program to demonstrate the use of constructor
GD.java
class GD
{
    int a;
    GD()
    {
        this(30);
    }
    GD(int a)
    {
        this.a=a;
        System.out.println(a);
    }
    public static void main(String args[])
    {
        GD k1=new GD();
    }
}
Output
godarda@gd:~$ javac GD.java
godarda@gd:~$ java GD
30
godarda@gd:~$
Example 4: Java program to demonstrate the use of constructor
GD.java
class Shape
{
    public Shape()
    {
        System.out.println("1");
        new Shape(10);
        System.out.println("2");
    }
    public Shape(int side)
    {
        System.out.println("3");
        new Shape(10,20);
        System.out.println("4");
    }
    public Shape(int width, int breadth)
    {
        System.out.println("5");
    }
}
class GD
{
    public static void main(String args[])
    {
        Shape s=new Shape();
    }
}
Output
godarda@gd:~$ javac GD.java
godarda@gd:~$ java GD
1
3
5
4
2
godarda@gd:~$
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