Refactored to extract common code

Added standard item to cucumber features

Java/src/main/java/com/gildedrose/AbstractItemQualityUpdater.java

@@ -0,0 +1,21 @@
+package com.gildedrose;
+
+public abstract class AbstractItemQualityUpdater implements ItemQualityUpdater {
+
+   protected Item item;
+
+   public AbstractItemQualityUpdater(Item item) {
+      this.item = item;
+   }
+
+   /**
+    * Decrease quality of an item, but never go below 0
+    * @param decrementValue Value the quality should be decreased by
+    */
+   void decreaseQuality(int decrementValue) {
+      item.quality = item.quality - decrementValue;
+      if (item.quality < 0) {
+         item.quality = 0;
+      }
+   }
+}

Java/src/main/java/com/gildedrose/BackstageQualityUpdater.java

@@ -1,10 +1,10 @@
 package com.gildedrose;
 
-public class BackstageBrieQualityUpdater implements ItemQualityUpdater {
+public class BackstageQualityUpdater implements ItemQualityUpdater {
 
    private final Item item;
 
-   public BackstageBrieQualityUpdater(Item item) {
+   public BackstageQualityUpdater(Item item) {
       this.item = item;
    }
 

Java/src/main/java/com/gildedrose/ConjuredQualityUpdater.java

@@ -1,30 +1,22 @@
 package com.gildedrose;
 
-public class ConjuredQualityUpdater implements ItemQualityUpdater {
+public class ConjuredQualityUpdater extends AbstractItemQualityUpdater {
 
-   private final Item item;
-   private final int normalDailyQualityDegradation = 2;
+   private final int dailyQualityDegradation = 2;
 
    public ConjuredQualityUpdater(Item item) {
-      this.item = item;
+      super(item);
    }
 
 
    @Override
    public void updateQuality() {
-      decreaseQuality(normalDailyQualityDegradation);
+      decreaseQuality(dailyQualityDegradation);
 
       item.sellIn = item.sellIn - 1;
 
       if (item.sellIn < 0) {
-         decreaseQuality(normalDailyQualityDegradation);
-      }
-   }
-
-   void decreaseQuality(int decrementValue) {
-      item.quality = item.quality - decrementValue;
-      if (item.quality < 0) {
-         item.quality = 0;
+         decreaseQuality(dailyQualityDegradation);
       }
    }
 }

Java/src/main/java/com/gildedrose/DefaultQualityUpdater.java

@@ -1,25 +1,20 @@
 package com.gildedrose;
 
-public class DefaultQualityUpdater implements ItemQualityUpdater {
-
-   private final Item item;
+public class DefaultQualityUpdater extends AbstractItemQualityUpdater {
+   private final int dailyQualityDegradation = 1;
 
    public DefaultQualityUpdater(Item item) {
-      this.item = item;
+      super(item);
    }
 
    @Override
    public void updateQuality() {
-      if (item.quality > 0) {
-         item.quality = item.quality - 1;
-      }
+      decreaseQuality(dailyQualityDegradation);
 
       item.sellIn = item.sellIn - 1;
 
       if (item.sellIn < 0) {
-         if (item.quality > 0) {
-            item.quality = item.quality - 1;
-         }
+         decreaseQuality(dailyQualityDegradation);
       }
    }
 }

Java/src/main/java/com/gildedrose/ItemQualityUpdateStrategyFactory.java

@@ -5,7 +5,7 @@ public class ItemQualityUpdateStrategyFactory {
       switch (item.name) {
          case "Sulfuras, Hand of Ragnaros": return new SulfrasQualityUpdater(item);
          case "Aged Brie": return new AgedBrieQualityUpdater(item);
-         case "Backstage passes to a TAFKAL80ETC concert": return new BackstageBrieQualityUpdater(item);
+         case "Backstage passes to a TAFKAL80ETC concert": return new BackstageQualityUpdater(item);
          case "Conjured": return new ConjuredQualityUpdater(item);
          default: return new DefaultQualityUpdater(item);
       }

Java/src/test/java/com/gildedrose/ItemQualityUpdateStrategyFactoryTest.java

@@ -10,7 +10,7 @@ class ItemQualityUpdateStrategyFactoryTest {
    void itemQualityUpdaterFor() {
       testFactoryFor("Sulfuras, Hand of Ragnaros", SulfrasQualityUpdater.class);
       testFactoryFor("Aged Brie", AgedBrieQualityUpdater.class);
-      testFactoryFor("Backstage passes to a TAFKAL80ETC concert", BackstageBrieQualityUpdater.class);
+      testFactoryFor("Backstage passes to a TAFKAL80ETC concert", BackstageQualityUpdater.class);
       testFactoryFor("xyz", DefaultQualityUpdater.class);
       testFactoryFor("Conjured", ConjuredQualityUpdater.class);
    }

Java/src/test/resources/com/gildedrose/conjured_quality_update.feature

@@ -11,4 +11,34 @@ Feature: Conjured items quality update
       | Conjured      | 3       | 2      | 1          | 1         |
       | Conjured      | 1       | 1      | 0          | 0         |
       | Conjured      | 6       | 0      | 2          | -1        |
-      | Conjured      | 4       | 0      | 0          | -1        |
+      | Conjured      | 4       | 0      | 0          | -1        |
+
+
+  Scenario Outline: Standard items quality degrades by 1 each day,
+  but degrade by 2 when sellIn is negative
+    Given name is "<name>", quality is "<quality>" and sellIn is "<sellIn>"
+    When I calculateQuality
+    Then I should have new quality "<newQuality>" and new sellIn "<newSellIn>"
+
+    Examples:
+      | name         | quality | sellIn  | newQuality | newSellIn |
+      | foo          | 0       | -1      | 0          | -2        |
+      | foo          | 1       | -1      | 0          | -2        |
+      | foo          | 49      | -1      | 47         | -2        |
+      | foo          | 50      | -1      | 48         | -2        |
+      | foo          | 0       | 0       | 0          | -1        |
+      | foo          | 1       | 0       | 0          | -1        |
+      | foo          | 49      | 0       | 47         | -1        |
+      | foo          | 50      | 0       | 48         | -1        |
+      | foo          | 0       | 5       | 0          | 4         |
+      | foo          | 1       | 5       | 0          | 4         |
+      | foo          | 49      | 5       | 48         | 4         |
+      | foo          | 50      | 5       | 49         | 4         |
+      | foo          | 0       | 6       | 0          | 5         |
+      | foo          | 1       | 6       | 0          | 5         |
+      | foo          | 49      | 6       | 48         | 5         |
+      | foo          | 50      | 6       | 49         | 5         |
+      | foo          | 0       | 11      | 0          | 10        |
+      | foo          | 1       | 11      | 0          | 10        |
+      | foo          | 49      | 11      | 48         | 10        |
+      | foo          | 50      | 11      | 49         | 10        |