// patterns/ShapeFactory3.java
// (c)2017 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.
// Polymorphic factory methods
import java.util.*;
import java.util.function.*;
import java.util.stream.*;
import patterns.shapes.*;

interface PolymorphicFactory {
 Shape create();
}

class RandomShapes implements Supplier<Shape> {
 private final PolymorphicFactory[] factories;
 private Random rand = new Random(42);
 RandomShapes(PolymorphicFactory... factories) {
 this.factories = factories;
 }
 public Shape get() {
 return factories[
 rand.nextInt(factories.length)].create();
 }
}

public class ShapeFactory3 {
 public static void main(String[] args) {
 RandomShapes rs = new RandomShapes(
 Circle::new, Square::new, Triangle::new
 );
 Stream.generate(rs)
 .limit(6)
 .peek(Shape::draw)
 .peek(Shape::erase)
 .count();
 }
}
/* Output:
Triangle[0] draw
Triangle[0] erase
Circle[1] draw
Circle[1] erase
Circle[2] draw
Circle[2] erase
Triangle[3] draw
Triangle[3] erase
Circle[4] draw
Circle[4] erase
Square[5] draw
Square[5] erase
*/