A.java

package p;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;

import edu.cuny.hunter.streamrefactoring.annotations.*;
import p.A.Widget.Color;

public class A {

	static class Widget {
		enum Color {
			RED, BLUE, GREEN, PINK, ORANGE, YELLOW
		};

		public Color getColor() {
			return this.getColor();
		}
	}

	/**
	 * P11 in table 3
	 */
	@EntryPoint
	void m() {
		Collection<Widget> orderedWidgets = new ArrayList<>();
		Map<Color, Set<Widget>> widgetsByColor = orderedWidgets.parallelStream()
				.collect(Collectors.groupingBy(Widget::getColor, HashMap::new, Collectors.toSet()));
	}
}