Improved sql.

src/main/java/com/songoda/ultimatestacker/database/DataManager.java

@@ -51,14 +51,11 @@ public class DataManager {
 
     public void updateSpawner(SpawnerStack spawnerStack) {
         this.async(() -> this.databaseConnector.connect(connection -> {
-            String updateSpawner = "UPDATE " + this.getTablePrefix() + "spawners SET amount = ? WHERE world = ? AND x = ? AND y = ? and z = ?";
+            String updateSpawner = "UPDATE " + this.getTablePrefix() + "spawners SET amount = ? WHERE id = ?";
             try (PreparedStatement statement = connection.prepareStatement(updateSpawner)) {
                 statement.setInt(1, spawnerStack.getAmount());
 
-                statement.setString(2, spawnerStack.getWorld().getName());
+                statement.setInt(2, spawnerStack.getId());
-                statement.setInt(3, spawnerStack.getX());
-                statement.setInt(4, spawnerStack.getY());
-                statement.setInt(5, spawnerStack.getZ());
                 statement.executeUpdate();
             }
         }));
@@ -67,6 +64,7 @@ public class DataManager {
 
     public void createSpawner(SpawnerStack spawnerStack) {
         this.async(() -> this.databaseConnector.connect(connection -> {
+
             String createSpawner = "INSERT INTO " + this.getTablePrefix() + "spawners (amount, world, x, y, z) VALUES (?, ?, ?, ?, ?)";
             try (PreparedStatement statement = connection.prepareStatement(createSpawner)) {
                 statement.setInt(1, spawnerStack.getAmount());
@@ -77,17 +75,16 @@ public class DataManager {
                 statement.setInt(5, spawnerStack.getZ());
                 statement.executeUpdate();
             }
+            int spawnerId = this.lastInsertedId(connection);
+            this.sync(() -> spawnerStack.setId(spawnerId));
         }));
     }
 
     public void deleteSpawner(SpawnerStack spawnerStack) {
         this.async(() -> this.databaseConnector.connect(connection -> {
-            String deleteSpawner = "DELETE FROM " + this.getTablePrefix() + "spawners WHERE world = ? AND x = ? AND y = ? and z = ?";
+            String deleteSpawner = "DELETE FROM " + this.getTablePrefix() + "spawners WHERE id = ?";
             try (PreparedStatement statement = connection.prepareStatement(deleteSpawner)) {
-                statement.setString(1, spawnerStack.getWorld().getName());
+                statement.setInt(1, spawnerStack.getId());
-                statement.setInt(2, spawnerStack.getX());
-                statement.setInt(3, spawnerStack.getY());
-                statement.setInt(4, spawnerStack.getZ());
                 statement.executeUpdate();
             }
         }));
@@ -103,6 +100,8 @@ public class DataManager {
                 ResultSet result = statement.executeQuery(selectSpawners);
                 while (result.next()) {
 
+                    int spawnerId = result.getInt("id");
+
                     int amount = result.getInt("amount");
 
                     String world = result.getString("world");
@@ -112,6 +111,7 @@ public class DataManager {
                     Location location = new Location(Bukkit.getWorld(world), x, y, z);
 
                     SpawnerStack spawnerStack = new SpawnerStack(location, amount);
+                    spawnerStack.setId(spawnerId);
                     spawners.put(location, spawnerStack);
                 }
             }

src/main/java/com/songoda/ultimatestacker/database/migrations/_1_InitialMigration.java

@@ -21,6 +21,7 @@ public class _1_InitialMigration extends DataMigration {
         // Create plugin settings table
         try (Statement statement = connection.createStatement()) {
             statement.execute("CREATE TABLE " + tablePrefix + "spawners (" +
+                    "id INTEGER PRIMARY KEY" + autoIncrement + ", " +
                     "amount INTEGER NOT NULL," +
                     "world TEXT NOT NULL, " +
                     "x DOUBLE NOT NULL, " +

src/main/java/com/songoda/ultimatestacker/spawner/SpawnerStack.java

@@ -13,6 +13,8 @@ import java.util.Random;
 
 public class SpawnerStack {
 
+    private int id;
+
     private final Location location;
     private int amount = 1;
 
@@ -46,6 +48,23 @@ public class SpawnerStack {
         }, 1L);
     }
 
+    public int calculateSpawnCount() {
+        Random random = new Random();
+        int count = 0;
+        for (int i = 0; i < getAmount(); i ++) {
+            count += random.nextInt(3 - 1 + 1) + 1;
+        }
+        return count;
+    }
+
+    public int getId() {
+        return this.id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
     public Location getLocation() {
         return location.clone();
     }
@@ -78,13 +97,4 @@ public class SpawnerStack {
                 + "}"
                 + "}";
     }
-
-    public int calculateSpawnCount() {
-        Random random = new Random();
-        int count = 0;
-        for (int i = 0; i < getAmount(); i ++) {
-            count += random.nextInt(3 - 1 + 1) + 1;
-        }
-        return count;
-    }
 }