Restructured and fixed application logic

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

@@ -1,62 +1,23 @@
 package com.gildedrose;
 
+import com.gildedrose.SellInUpdater;
+import com.gildedrose.QualityUpdater;
+
 class GildedRose {
     Item[] items;
+    SellInUpdater sellInUpdater = new SellInUpdater();
+    QualityUpdater qualityUpdater = new QualityUpdater();
 
     public GildedRose(Item[] items) {
         this.items = items;
     }
 
-    public void updateQuality() {
-        for (int i = 0; i < items.length; i++) {
-            if (!items[i].name.equals("Aged Brie")
-                    && !items[i].name.equals("Backstage passes to a TAFKAL80ETC concert")) {
-                if (items[i].quality > 0) {
-                    if (!items[i].name.equals("Sulfuras, Hand of Ragnaros")) {
-                        items[i].quality = items[i].quality - 1;
-                    }
-                }
-            } else {
-                if (items[i].quality < 50) {
-                    items[i].quality = items[i].quality + 1;
-
-                    if (items[i].name.equals("Backstage passes to a TAFKAL80ETC concert")) {
-                        if (items[i].sellIn < 11) {
-                            if (items[i].quality < 50) {
-                                items[i].quality = items[i].quality + 1;
-                            }
-                        }
-
-                        if (items[i].sellIn < 6) {
-                            if (items[i].quality < 50) {
-                                items[i].quality = items[i].quality + 1;
-                            }
-                        }
-                    }
-                }
-            }
-
-            if (!items[i].name.equals("Sulfuras, Hand of Ragnaros")) {
-                items[i].sellIn = items[i].sellIn - 1;
-            }
-
-            if (items[i].sellIn < 0) {
-                if (!items[i].name.equals("Aged Brie")) {
-                    if (!items[i].name.equals("Backstage passes to a TAFKAL80ETC concert")) {
-                        if (items[i].quality > 0) {
-                            if (!items[i].name.equals("Sulfuras, Hand of Ragnaros")) {
-                                items[i].quality = items[i].quality - 1;
-                            }
-                        }
-                    } else {
-                        items[i].quality = items[i].quality - items[i].quality;
-                    }
-                } else {
-                    if (items[i].quality < 50) {
-                        items[i].quality = items[i].quality + 1;
-                    }
-                }
-            }
+    //For each item update the SellIn value and adjust quality accordingly
+    public void updateQuality() throws Exception {
+        for (Item item : items) {
+            sellInUpdater.updateSellInValue(item);
+            qualityUpdater.updateQualityForItem(item);
         }
     }
+
 }

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

@@ -0,0 +1,106 @@
+package com.gildedrose;
+
+public class QualityUpdater {
+
+    //Find items with exceptional quality rules
+    public void updateQualityForItem(Item item) throws Exception {
+        switch(item.name.substring(0,9)) {
+            case "Aged Brie":
+                updateNonDegradingItemQuality(item);
+                break;
+            case "Sulfuras,":
+                updateLegendaryItemQuality(item);
+                break;
+            case "Backstage":
+                updateBackstagePassQuality(item);
+                break;
+            case "Conjured ":
+                updateConjuredItemQuality(item);
+                break;
+            default:
+                updateRegularItemQuality(item);
+        }
+    }
+
+    //Increase quality of items which cannot degrade
+    private void updateNonDegradingItemQuality(Item item) throws Exception {
+        if (item.sellIn >= 0) {
+            adjustQuality(item, "increase",1);
+        }
+        else {
+            adjustQuality(item, "increase",2);
+        }
+        makeSureQualityIsInRange(item, 50,0);
+    }
+
+    //Set legendary item quality to 80 as it can never be different
+    private void updateLegendaryItemQuality(Item item) {
+        makeSureQualityIsInRange(item, 80,80);
+    }
+
+    //Increase quality of backstage passes as the concert date nears, after the concert quality drops to 0
+    private void updateBackstagePassQuality(Item item) throws Exception {
+        if (item.sellIn > 10) {
+            adjustQuality(item, "increase",1);
+        }
+        if (item.sellIn <= 10 && item.sellIn > 5) {
+            adjustQuality(item, "increase",2);
+        }
+        if (item.sellIn <= 5 && item.sellIn >= 0) {
+            adjustQuality(item, "increase",3);
+        }
+        if (item.sellIn < 0) {
+            adjustQuality(item, "set",0);
+        }
+        makeSureQualityIsInRange(item, 50,0);
+    }
+
+    //Decrease quality of conjured items fast
+    private void updateConjuredItemQuality(Item item) throws Exception {
+        if (item.sellIn >= 0) {
+            adjustQuality(item, "decrease",2);
+        }
+        else {
+            adjustQuality(item, "decrease",4);
+        }
+        makeSureQualityIsInRange(item, 50,0);
+    }
+
+    //Decrease quality of item types not specified above
+    private void updateRegularItemQuality(Item item) throws Exception {
+        if (item.sellIn >= 0) {
+            adjustQuality(item, "decrease",1);
+        }
+        else {
+            adjustQuality(item, "decrease",2);
+        }
+        makeSureQualityIsInRange(item, 50,0);
+    }
+
+    //Adjust the item quality with previously specified value
+    private void adjustQuality(Item item, String adjustment , int value) throws Exception {
+        switch (adjustment) {
+            case "increase":
+                item.quality = item.quality + value;
+                break;
+            case "decrease":
+                item.quality = item.quality - value;
+                break;
+            case "set":
+                item.quality = value;
+                break;
+            default:
+                throw new Exception("Unknown quality adjustment: "+adjustment);
+        }
+    }
+
+    //Make sure the quality never goes beyond the set boundaries
+    private void makeSureQualityIsInRange(Item item, int qualityIsNeverAbove, int qualityIsNeverBelow) {
+        if (item.quality > qualityIsNeverAbove) {
+            item.quality = qualityIsNeverAbove;
+        }
+        if (item.quality < qualityIsNeverBelow) {
+            item.quality = qualityIsNeverBelow;
+        }
+    }
+}

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

@@ -0,0 +1,20 @@
+package com.gildedrose;
+
+public class SellInUpdater {
+
+    //Decrease the sellIn date of non-legendary items with every passing day
+    public void updateSellInValue(Item item) {
+        if (isNoLegendaryItem(item)) {
+            item.sellIn = item.sellIn - 1;
+        }
+    }
+
+    //Check if the item isn't legendary
+    private boolean isNoLegendaryItem(Item item) {
+        if (item.name.startsWith("Sulfuras,")) {
+            return false;
+        } else {
+            return true;
+        }
+    }
+}

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

@@ -1,7 +1,7 @@
 package com.gildedrose;
 
 public class TexttestFixture {
-    public static void main(String[] args) {
+    public static void main(String[] args) throws Exception {
         System.out.println("OMGHAI!");
 
         Item[] items = new Item[] {
@@ -18,7 +18,7 @@ public class TexttestFixture {
 
         GildedRose app = new GildedRose(items);
 
-        int days = 2;
+        int days = 100;
         if (args.length > 0) {
             days = Integer.parseInt(args[0]) + 1;
         }