this piece of code is for expert java developers

import java.io.IOException; public clbum Arcane1 { 
    public static void main(String[] args) { 
        try { 
            System.out.println("Hello world"); 
        } catch (IOException e) { 
            System.out.println("I've never seen println fail!"); 
        } 
    } 
} 
public clbum Arcane2 { 
    public static void main(String[] args) { 
        try { 
            // If you have nothing nice to say, say nothing 
        } catch (Exception e) { 
            System.out.println("This can't happen"); 
        } 
    } 
} 
interface Type1 { 
    void f() throws CloneNotSupportedException; 
} 
interface Type2 { 
    void f() throws InterruptedException; 
} 
interface Type3 extends Type1, Type2 { 
} 
public clbum Arcane3 implements Type3 { 
    public void f() { 
        System.out.println("Hello world"); 
    } 
    public static void main(String[] args) { 
        Type3 t3 = new Arcane3(); 
        t3.f(); 
    } 
} 

what does it do and why?