Fixed stupid memory lag. Managers are now using Singleton-pattern!

src/main/java/de/skate702/craftingkeys/CraftingKeys.java

@@ -107,7 +107,7 @@ public class CraftingKeys {
 
             if (currentScreen instanceof GuiCrafting) {
 
-                ContainerManager con = new CraftingManager(
+                ContainerManager con = CraftingManager.getInstance(
                         ((GuiCrafting) currentScreen).inventorySlots);
                 con.acceptKey();
 

src/main/java/de/skate702/craftingkeys/manager/ContainerManager.java

@@ -21,7 +21,7 @@ public abstract class ContainerManager {
      *
      * @param container The container to work with
      */
-    public ContainerManager(Container container) {
+    protected ContainerManager(Container container) {
         this.container = container;
     }
 

src/main/java/de/skate702/craftingkeys/manager/CraftingManager.java

@@ -12,15 +12,32 @@ import org.lwjgl.input.Keyboard;
 
 public class CraftingManager extends ContainerManager {
 
+    private static CraftingManager instance = null;
+
     /**
      * Creates a new Crafting Manager with the given container.
      *
      * @param container The container from a crafting GUI
      */
-    public CraftingManager(Container container) {
+    private CraftingManager(Container container) {
         super(container);
     }
 
+    /**
+     * Returns a Crafting Manager Instance operating on the given container
+     *
+     * @param container A container from a GUI
+     * @return manager-singleton
+     */
+    public static CraftingManager getInstance(Container container) {
+        if (instance == null) {
+            instance = new CraftingManager(container);
+        } else {
+            instance.container = container;
+        }
+        return instance;
+    }
+
     @Override
     public void acceptKey() {