OnJava8-Examples/generics/LostInformation.java at master · CSapprenticeWT/OnJava8-Examples · GitHub

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// generics/LostInformation.java

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

import java.util.*;

class Frob {}

class Fnorkle {}

class Quark<Q> {}

class Particle<POSITION, MOMENTUM> {}

public class LostInformation {

public static void main(String[] args) {

List<Frob> list = new ArrayList<>();

Map<Frob, Fnorkle> map = new HashMap<>();

Quark<Fnorkle> quark = new Quark<>();

Particle<Long, Double> p = new Particle<>();

System.out.println(Arrays.toString(

list.getClass().getTypeParameters()));

System.out.println(Arrays.toString(

map.getClass().getTypeParameters()));

System.out.println(Arrays.toString(

quark.getClass().getTypeParameters()));

System.out.println(Arrays.toString(

p.getClass().getTypeParameters()));

}

/* Output:

[E]

[K, V]

[Q]

[POSITION, MOMENTUM]