Add support for spawners with entities on 1.13+

Essentials/src/com/earth2me/essentials/items/FlatItemDb.java

@@ -8,11 +8,11 @@ import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
 import net.ess3.api.IEssentials;
 import org.bukkit.Material;
+import org.bukkit.entity.EntityType;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.Damageable;
 import org.bukkit.inventory.meta.ItemMeta;
 import org.bukkit.inventory.meta.PotionMeta;
-import org.bukkit.inventory.meta.Repairable;
 import org.bukkit.potion.PotionData;
 
 import java.util.*;
@@ -24,10 +24,8 @@ import static com.earth2me.essentials.I18n.tl;
 
 public class FlatItemDb extends AbstractItemDb {
     protected static final Logger LOGGER = Logger.getLogger("Essentials");
-    private final transient IEssentials ess;
-
     private static Gson gson = new Gson();
-
+    private final transient IEssentials ess;
     // Maps primary name to ItemData
     private final transient Map<String, ItemData> items = new HashMap<>();
 
@@ -57,9 +55,9 @@ public class FlatItemDb extends AbstractItemDb {
         this.reset();
 
         String json = file.getLines().stream()
-                .filter(line -> !line.startsWith("#"))
-                .collect(Collectors.joining());
-        
+            .filter(line -> !line.startsWith("#"))
+            .collect(Collectors.joining());
+
         this.loadJSON(String.join("\n", json));
     }
 
@@ -108,12 +106,12 @@ public class FlatItemDb extends AbstractItemDb {
             throw new Exception(tl("unknownItemName", id));
         }
 
-        PotionData potionData = data.getPotionData();
         Material material = data.getMaterial();
 
         ItemStack stack = new ItemStack(material);
         stack.setAmount(material.getMaxStackSize());
 
+        PotionData potionData = data.getPotionData();
         ItemMeta meta = stack.getItemMeta();
 
         if (potionData != null && meta instanceof PotionMeta) {
@@ -130,6 +128,13 @@ public class FlatItemDb extends AbstractItemDb {
 
         stack.setItemMeta(meta);
 
+        // The spawner provider will update the meta again, so we need to call it after
+        // setItemMeta to prevent a race condition
+        EntityType entity = data.getEntity();
+        if (entity != null && material.toString().contains("SPAWNER")) {
+            ess.getSpawnerProvider().setEntityType(stack, entity);
+        }
+
         return stack;
     }
 
@@ -161,14 +166,7 @@ public class FlatItemDb extends AbstractItemDb {
 
     @Override
     public String name(ItemStack item) {
-        Material type = item.getType();
-        PotionData potion = null;
-
-        if (MaterialUtil.isPotion(type) && item.getItemMeta() instanceof PotionMeta) {
-            potion = ((PotionMeta) item.getItemMeta()).getBasePotionData();
-        }
-
-        ItemData data = new ItemData(type, potion);
+        ItemData data = lookup(item);
 
         for (Map.Entry<String, ItemData> entry : items.entrySet()) {
             if (entry.getValue().equals(data)) {
@@ -185,20 +183,44 @@ public class FlatItemDb extends AbstractItemDb {
         throw new UnsupportedOperationException("Legacy IDs aren't supported on this version.");
     }
 
+    public ItemData lookup(ItemStack item) {
+        Material type = item.getType();
+
+        if (MaterialUtil.isPotion(type) && item.getItemMeta() instanceof PotionMeta) {
+            PotionData potion = ((PotionMeta) item.getItemMeta()).getBasePotionData();
+            return new ItemData(type, potion);
+        } else if (type.toString().contains("SPAWNER")) {
+            EntityType entity = ess.getSpawnerProvider().getEntityType(item);
+            return new ItemData(type, entity);
+        } else {
+            return new ItemData(type);
+        }
+    }
+
     @Override
     public Collection<String> listNames() {
         return Collections.unmodifiableSet(allAliases);
     }
 
     public static class ItemData {
-        private Material material;
-        private PotionData potionData;
+        private final Material material;
+        private PotionData potionData = null;
+        private EntityType entity = null;
+
+        public ItemData(Material material) {
+            this.material = material;
+        }
 
         public ItemData(Material material, PotionData potionData) {
             this.material = material;
             this.potionData = potionData;
         }
 
+        public ItemData(Material material, EntityType entity) {
+            this.material = material;
+            this.entity = entity;
+        }
+
         @Override
         public int hashCode() {
             return (31 * material.hashCode()) ^ potionData.hashCode();
@@ -213,7 +235,7 @@ public class FlatItemDb extends AbstractItemDb {
                 return false;
             }
             ItemData that = (ItemData) o;
-            return this.material == that.getMaterial() && potionDataEquals(that);
+            return this.material == that.getMaterial() && potionDataEquals(that) && entityEquals(that);
         }
 
         public Material getMaterial() {
@@ -224,6 +246,10 @@ public class FlatItemDb extends AbstractItemDb {
             return this.potionData;
         }
 
+        public EntityType getEntity() {
+            return this.entity;
+        }
+
         private boolean potionDataEquals(ItemData o) {
             if (this.potionData == null && o.getPotionData() == null) {
                 return true;
@@ -233,5 +259,15 @@ public class FlatItemDb extends AbstractItemDb {
                 return false;
             }
         }
+
+        private boolean entityEquals(ItemData o) {
+            if (this.entity == null && o.getEntity() == null) { // neither have an entity
+                return true;
+            } else if (this.entity != null && o.getEntity() != null) { // both have an entity; check if it's the same one
+                return this.entity.equals(o.getEntity());
+            } else { // one has an entity but the other doesn't, so they can't be equal
+                return false;
+            }
+        }
     }
 }