import tester.Tester;

// some grocery items 
interface IItem 
{ 
	// is this the same IItem as other? 
	boolean same(IItem x); 
	// is this Coffee? 
	boolean isCoffee(); 
	// convert this to Coffee (if feasible) 
	Coffee toCoffee(); 
	// is this Tea? 
	boolean isTea(); 
	// convert this to Tea (if feasible) 
	Tea toTea(); 
} 


class Coffee implements IItem 
{ 
	private String origin; 
	private int price; 
	Coffee(String origin, int price) 
	{ 
		this.origin = origin; 
		this.price = price; 
	} 
	public boolean isCoffee() 
	{ 
		return true; 
	} 
	public boolean isTea() 
	{ 
		return false; 
	} 
	public Coffee toCoffee() 
	{ 
		return this; 
	} 
	public Tea toTea() 
	{ 
		throw new RuntimeException("not a tea"); 
	} 
	public boolean same(IItem other) 
	{ 
		return (other.isCoffee()) 
		&& other.toCoffee().same(this); 
	} 
	// is this the same Coffee as other? 
	private boolean same(Coffee other) 
	{ 
		return 
		this.origin.equals(other.origin) 
		&& this.price == other.price; 
	} 
} 
class Tea implements IItem 
{ 
	private String kind; 
	private int price; 
	Tea(String kind, int price) 
	{ 
		this.kind = kind; 
		this.price = price; 
	} 
	public boolean isTea() 
	{ 
		return true; 
	} 
	public boolean isCoffee() 
	{ 
		return false; 
	} 
	public Tea toTea() 
	{ 
		return this; 
	} 
	public Coffee toCoffee() 
	{ 
		throw new RuntimeException("not a coffee"); 
	} 
	public boolean same(IItem other) 
	{ 
		return other.isTea() 
		&& other.toTea().same(this); 
	} 
	// is this the same Tea as other? 
	private boolean same(Tea other) 
	{ 
		return 
		this.kind.equals(other.kind) 
		&& this.price == other.price; 
	} 
} 

class Examples{
	Examples(){}
	
	IItem tea1 = new Tea("Oolong", 200);
	IItem tea2 = new Tea("Oolong", 300);
	IItem coffee1 = new Tea("Kona", 300);
	IItem coffee2 = new Tea("Java", 200);
	
	boolean t1t2 = tea1.same(tea2);
	boolean c1c2 = coffee1.same(coffee2);	
	boolean tc() {return tea1.same(coffee1);}	
	boolean ct() {return coffee1.same(tea2);}	

	
	public static void main(String[] argv){
		Examples e = new Examples();
		System.out.println(e.t1t2);
		System.out.println(e.c1c2);
		try{
		System.out.println(e.tc());
		} catch(RuntimeException ex){
			System.out.println(ex.getMessage());
		}
		try{
			System.out.println(e.ct());
			} catch(RuntimeException ex){
				System.out.println(ex.getMessage());
			}
	}
}