Inheritance of Interface: An upbeat program

interface P
{
	final int p = 1;
	void p_method();
}

interface P1 extends P
{
	final int p1 = 2;
	
	void p1_method();
}

interface P2 extends P
{
	final int p2 = 3;
	
	 void p2_method();
}

interface P12 extends P1, P2
{
	final int p12 = 4;
	
	 void p12_method();
}

class Class implements P12
{
	public void p_method()
	{
		System.out.println("Hello from P");
		System.out.println("P => " + p);
	}
	public void p1_method()
	{
		System.out.println("Hello from P1");
		System.out.println("P1 => " + p1);
	}
	public void p2_method()
	{
		System.out.println("Hello from P2");
		System.out.println("P2 => " + p2);
	}
	public void p12_method()
	{
		System.out.println("Hello from P12");
		System.out.println("P12 => " + p12);
	}
}

public class Practical17
{
	public static void main(String[] args)
	{
		P12 pr = new Class();
		pr.p_method();
		pr.p1_method();
		pr.p2_method();
		pr.p12_method();
	}
}