//
// a first try at implementing Cloneable
//

class Try1 implements Cloneable {

        int single ;
        int[] pair = new int[2] ;

        Try1(int a, int b, int c) {
                single = a ;
                pair[0] = b ;
                pair[1] = c ;
        }

        // override this method of Object class to provide nice
        //      printing
        public String toString() {
                return single + " " + pair[0] + " " + pair[1] ;
        }

        // provide this method to implement Cloneable
        public Object clone() {
                try {
                        // use Object class clone()
                        return super.clone() ;
                }
                catch (CloneNotSupportedException e) {
                        throw new Error("This should not happen!") ;
                }
        }
}

//
// a second (better) try at implementing Cloneable
//
class Try2 implements Cloneable {

        int single ;
        int[] pair = new int[2] ;

        Try2(int a, int b, int c) {
                single = a ;
                pair[0] = b ;
                pair[1] = c ;
        }

        // override this method of Object class to provide nice
        //      printing
        public String toString() {
                return single + " " + pair[0] + " " + pair[1] ;
        }

        // provide this method to implement Cloneable
        public Object clone() {
                try {
                        // note typecasts
                        Try2 copy = (Try2) super.clone() ; 
                        copy.pair = (int [])pair.clone() ;
                        return copy ;
                }
                catch (CloneNotSupportedException e) {
                        throw new Error("This should not happen!") ;
                }
        }
}

public class Clones {

        public static void main(String[] args) {

                // try the first way

                System.out.println("First try at cloning:") ;
                Try1 x1 = new Try1(1, 2, 3) ;
                Try1 x2 = (Try1) x1.clone() ;   // note typecast

                System.out.println("x1 = " + x1) ;
                System.out.println("x2 (clone of x1) = " + x2) ;

                System.out.println("Changing x1") ;
                x1.single = 10 ;
                x1.pair[0] = 20 ;

                System.out.println("x1 = " + x1) ;
                System.out.println("x2 = " + x2) ;

                // try the second way

                System.out.println("") ;
                System.out.println("Second try at cloning:") ;
                Try2 y1 = new Try2(1, 2, 3) ;
                Try2 y2 = (Try2) y1.clone() ;   // note typecast

                System.out.println("y1 = " + y1) ;
                System.out.println("y2 (clone of y1) = " + y2) ;

                System.out.println("Changing y1") ;
                y1.single = 10 ;
                y1.pair[0] = 20 ;

                System.out.println("y1 = " + y1) ;
                System.out.println("y2 = " + y2) ;

        }
}