java泛型元组

package generics;
class Amphibian{};
class Vehicle{};
public class TupleTest {
static TwoTuple<String ,Integer> f(){
return new TwoTuple<String, Integer>("hi", 47);
}
static ThreeTuple<Amphibian,String ,Integer> g(){
return new ThreeTuple<Amphibian,String, Integer>(new Amphibian(),"hi", 47);
}
static FourTuple<Vehicle,Amphibian,String ,Integer> h(){
return new FourTuple<Vehicle,Amphibian,String, Integer>(new Vehicle(),new Amphibian(),"hi", 47);
}
static FiveTuple<Vehicle,Amphibian,String ,Integer,Double> k(){
return new FiveTuple <Vehicle,Amphibian,String, Integer,Double>(new Vehicle(),new Amphibian(),"hi", 47,11.1);
}
public static void main(String[] args) {
TwoTuple<String, Integer> ttsi=f();
System.out.println(ttsi);

}
}