Fix facade recipes. Hopefully the last null check fix.

src/main/java/appeng/recipes/Ingredient.java

@@ -24,6 +24,7 @@ import java.util.List;
 import com.google.common.base.Preconditions;
 
 import net.minecraft.block.Block;
+import net.minecraft.init.Items;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
@@ -167,7 +168,7 @@ public class Ingredient implements IIngredient
 		if( blk != null )
 		{
 			final Item it = Item.getItemFromBlock( blk );
-			if( it != null )
+			if( it != Items.AIR )
 			{
 				return this.makeItemStack( it, this.qty, this.meta, this.nbt );
 			}

src/main/java/appeng/recipes/game/DisassembleRecipe.java

@@ -78,7 +78,7 @@ public final class DisassembleRecipe implements IRecipe
 	@Override
 	public boolean matches( final InventoryCrafting inv, final World w )
 	{
-		return this.getOutput( inv ) != null;
+		return !this.getOutput( inv ).isEmpty();
 	}
 
 	@Nullable
@@ -111,7 +111,7 @@ public final class DisassembleRecipe implements IRecipe
 						final IItemList<IAEItemStack> list = cellInv.getAvailableItems( StorageChannel.ITEMS.createList() );
 						if( !list.isEmpty() )
 						{
-							return null;
+							return ItemStack.EMPTY;
 						}
 					}
 

src/main/java/appeng/recipes/game/FacadeRecipe.java

@@ -51,7 +51,7 @@ public final class FacadeRecipe implements IRecipe
 	@Override
 	public boolean matches( final InventoryCrafting inv, final World w )
 	{
-		return this.getOutput( inv, false ) != null;
+		return !this.getOutput( inv, false ).isEmpty();
 	}
 
 	@Nullable
@@ -62,7 +62,7 @@ public final class FacadeRecipe implements IRecipe
 			if( this.anchor.isSameAs( inv.getStackInSlot( 1 ) ) && this.anchor.isSameAs( inv.getStackInSlot( 3 ) ) && this.anchor.isSameAs( inv.getStackInSlot( 5 ) ) && this.anchor.isSameAs( inv.getStackInSlot( 7 ) ) )
 			{
 				final ItemStack facades = facade.createFacadeForItem( inv.getStackInSlot( 4 ), !createFacade );
-				if( facades != null && createFacade )
+				if( !facades.isEmpty() && createFacade )
 				{
 					facades.setCount( 4 );
 				}
@@ -70,7 +70,7 @@ public final class FacadeRecipe implements IRecipe
 			}
 		}
 
-		return null;
+		return ItemStack.EMPTY;
 	}
 
 	@Override

src/main/java/appeng/recipes/handlers/Smelt.java

@@ -21,6 +21,7 @@ package appeng.recipes.handlers;
 
 import java.util.List;
 
+import net.minecraft.init.Items;
 import net.minecraft.item.ItemStack;
 import net.minecraftforge.fml.common.registry.GameRegistry;
 
@@ -59,12 +60,12 @@ public class Smelt implements ICraftHandler, IWebsiteSerializer
 	@Override
 	public void register() throws RegistrationError, MissingIngredientError
 	{
-		if( this.in.getItemStack().getItem() == null )
+		if( this.in.getItemStack().getItem() == Items.AIR )
 		{
 			throw new RegistrationError( this.in.toString() + ": Smelting Input is not a valid item." );
 		}
 
-		if( this.out.getItemStack().getItem() == null )
+		if( this.out.getItemStack().getItem() == Items.AIR )
 		{
 			throw new RegistrationError( this.out.toString() + ": Smelting Output is not a valid item." );
 		}

src/main/java/appeng/recipes/ores/OreDictionaryHandler.java

@@ -43,7 +43,7 @@ public class OreDictionaryHandler
 	@SubscribeEvent
 	public void onOreDictionaryRegister( final OreDictionary.OreRegisterEvent event )
 	{
-		if( event.getName() == null || event.getOre() == null )
+		if( event.getName() == null || event.getOre().isEmpty() )
 		{
 			return;
 		}
@@ -111,7 +111,7 @@ public class OreDictionaryHandler
 			{
 				for( final ItemStack item : OreDictionary.getOres( name ) )
 				{
-					if( item != null )
+					if( !item.isEmpty() )
 					{
 						n.oreRegistered( name, item );
 					}