// Example 122 from page 93

//

import java.util.*;

// A constraint may involve type parameters

// A type may have multiple constraints

class ComparablePair<T extends Comparable<T>, U extends Comparable<U>>

implements Comparable<ComparablePair<T,U>>

{

public final T fst;

public final U snd;

public ComparablePair(T fst, U snd) {

this.fst = fst; this.snd = snd;

}

// Lexicographic ordering

@Override

public int compareTo(ComparablePair<T,U> that) {

int firstCmp = this.fst.compareTo(that.fst);

return firstCmp != 0 ? firstCmp : this.snd.compareTo(that.snd);

}

@Override

public String toString() {

return "(" + fst + ", " + snd + ")";

}

}

// Sorting soccer world champions by country and year

class Example122 {

public static void main(String[] args) {

ArrayList<ComparablePair<String,Integer>> lst

= new ArrayList<ComparablePair<String,Integer>>();

lst.add(new ComparablePair<String,Integer>("Brazil", 2002));

lst.add(new ComparablePair<String,Integer>("Italy", 1982));

lst.add(new ComparablePair<String,Integer>("Argentina", 1978 ));

lst.add(new ComparablePair<String,Integer>("Argentina", 1986 ));

lst.add(new ComparablePair<String,Integer>("Germany", 1990));

lst.add(new ComparablePair<String,Integer>("Brazil", 1994));

lst.add(new ComparablePair<String,Integer>("France", 1998));

Collections.sort(lst);

for (ComparablePair<String,Integer> pair : lst)

System.out.println(pair);

}

}