// reflection/pets/Creator.java

// (c)2021 MindView LLC: see Copyright.txt

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

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

// Creates random Pets

package reflection.pets;

import java.lang.reflect.InvocationTargetException;

import java.util.ArrayList;

import java.util.List;

import java.util.Random;

import java.util.function.Supplier;

import java.util.stream.Collectors;

import java.util.stream.Stream;

public abstract class Creator implements Supplier<reflection.pets.Pet> {

private Random rand = new Random(47);

// The different types of Pet to create:

public abstract List<Class<? extends reflection.pets.Pet>> types();

@Override

public reflection.pets.Pet get() { // Create one random Pet

int n = rand.nextInt(types().size());

try {

return types().get(n)

.getConstructor().newInstance();

} catch (InstantiationException |

NoSuchMethodException |

InvocationTargetException |

IllegalAccessException e) {

throw new RuntimeException(e);

}

}

public Stream<reflection.pets.Pet> stream() {

return Stream.generate(this);

}

public reflection.pets.Pet[] array(int size) {

return stream().limit(size).toArray(reflection.pets.Pet[]::new);

}

public List<reflection.pets.Pet> list(int size) {

return stream().limit(size)

.collect(Collectors.toCollection(ArrayList::new));

}

}