Set

import java.util.*;

class SetType{
    int i;
    public SetType(int n){ this.i = n;}
    public boolean equals(Object o){
        return o instanceof SetType && (this.i == ((SetType)o).i);
    }
    @Override
    public String toString() {
        return Integer.toString(i);
    }
    
}
class HashType extends SetType{
    public HashType(int n) {super(n);}
    public int hashCode(){return i;}
}
class TreeType extends SetType implements Comparable<TreeType>{
    public TreeType(int n){super(n);}
    
    public int compareTo(TreeType o){
        return (o.i<i?-1: (o.i ==i ?0:1));
}
}

public class TypesForSets {
    static <T> Set<T>  fill(Set<T> set,Class<T> type)
    {
        try{
            for(int i=0;i<10;i++){
                //下面代码什么鬼？
                set.add(type.getConstructor(int.class).newInstance(i));
            }
        }catch(Exception e){
            throw new RuntimeException(e);
        }
        
        return set;
        
    }
    static <T> void test(Set<T> set,Class<T> type ){
        fill(set,type);
        fill(set,type); //try to add duplicates
        fill(set,type);
        System.out.println(set);
    }
    
    public static void main(String[] args) {
        //test(new HashSet<HashType>(),HashType.class);
        //test(new LinkedHashSet<HashType>(),HashType.class);
        //test(new TreeSet<TreeType>(),TreeType.class);
        
        //Things that don't work:
        //test(new HashSet<SetType>(),HashType.class);
        
        Set<String> set = new LinkedHashSet<String>();
        set.add("Bob");
        set.add("Allen");
        set.add("Carb");
        
        System.out.println(set);
        
    }

}