added flyweight sample

flyweight/src/main/java/com/iluwatar/PotionFactory.java

@@ -0,0 +1,39 @@
+package com.iluwatar;
+
+import java.util.EnumMap;
+
+public class PotionFactory {
+
+	private EnumMap<PotionType, Potion> potions;
+	
+	public PotionFactory() {
+		potions = new EnumMap<>(PotionType.class);
+	}
+	
+	Potion createPotion(PotionType type) {
+		Potion potion = potions.get(type);
+		if (potion == null) {
+			switch (type) {
+			case HEALING:
+				potion = new HealingPotion();
+				break;
+			case HOLY_WATER:
+				potion = new HolyWaterPotion();
+				break;
+			case INVISIBILITY:
+				potion = new InvisibilityPotion();
+				break;
+			case POISON:
+				potion = new PoisonPotion();
+				break;
+			case STRENGTH:
+				potion = new StrengthPotion();
+				break;
+			default:
+				break;
+			}
+		}
+		return potion;
+	}
+	
+}