Fix facade recipes. Hopefully the last null check fix.

src/main/java/appeng/util/InWorldToolOperationResult.java

@@ -58,7 +58,7 @@ public class InWorldToolOperationResult
 
 		for( final ItemStack l : items )
 		{
-			if( b == null )
+			if( b.isEmpty() )
 			{
 				final Block bl = Block.getBlockFromItem( l.getItem() );
 

src/main/java/appeng/util/Platform.java

@@ -681,7 +681,7 @@ public class Platform
 			return new ArrayList();
 		}
 
-		ItemStack itemStack = null;
+		ItemStack itemStack = ItemStack.EMPTY;
 		if( o instanceof AEItemStack )
 		{
 			final AEItemStack ais = (AEItemStack) o;
@@ -724,7 +724,7 @@ public class Platform
 			return "** Null";
 		}
 
-		ItemStack itemStack = null;
+		ItemStack itemStack = ItemStack.EMPTY;
 		if( o instanceof AEItemStack )
 		{
 			final String n = ( (AEItemStack) o ).getDisplayName();

src/main/java/appeng/util/helpers/ItemComparisonHelper.java

@@ -26,6 +26,7 @@ import java.util.Set;
 
 import javax.annotation.Nullable;
 
+import net.minecraft.init.Items;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTBase;
@@ -140,7 +141,7 @@ public class ItemComparisonHelper
 		 */
 
 		// test damageable items..
-		if( a.getItem() != null && b.getItem() != null && a.getItem().isDamageable() && a.getItem() == b.getItem() )
+		if( a.getItem() != Items.AIR && b.getItem() != Items.AIR && a.getItem().isDamageable() && a.getItem() == b.getItem() )
 		{
 			try
 			{
@@ -379,11 +380,11 @@ public class ItemComparisonHelper
 	 */
 	private boolean hasSameNbtTag( final ItemStack a, final ItemStack b )
 	{
-		if( a == null && b == null )
+		if( a.isEmpty() && b.isEmpty() )
 		{
 			return true;
 		}
-		if( a == null || b == null )
+		if( a.isEmpty() || b.isEmpty() )
 		{
 			return false;
 		}

src/main/java/appeng/util/item/AEItemStack.java

@@ -31,6 +31,7 @@ import javax.annotation.Nullable;
 
 import io.netty.buffer.ByteBuf;
 
+import net.minecraft.init.Items;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.CompressedStreamTools;
@@ -68,14 +69,14 @@ public final class AEItemStack extends AEStack<IAEItemStack> implements IAEItemS
 		}
 
 		final Item item = is.getItem();
-		if( item == null )
+		if( item == Items.AIR )
 		{
 			throw new InvalidParameterException( "Contained item is null, thus not a valid ItemStack for AEItemStack." );
 		}
 
 		this.setDefinition( new AEItemDef( item ) );
 
-		if( this.getDefinition().getItem() == null )
+		if( this.getDefinition().getItem() == Items.AIR )
 		{
 			throw new InvalidParameterException( "This ItemStack is bad, it has a null item." );
 		}

src/main/java/appeng/util/item/AESharedNBT.java

@@ -22,6 +22,7 @@ package appeng.util.item;
 import java.lang.ref.WeakReference;
 import java.util.WeakHashMap;
 
+import net.minecraft.init.Items;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
@@ -81,7 +82,7 @@ public class AESharedNBT extends NBTTagCompound implements IAETagCompound
 
 		final Item item = s.getItem();
 		int meta = -1;
-		if( s.getItem() != null && s.isItemStackDamageable() && s.getHasSubtypes() )
+		if( s.getItem() != Items.AIR && s.isItemStackDamageable() && s.getHasSubtypes() )
 		{
 			meta = s.getItemDamage();
 		}

src/main/java/appeng/util/item/OreReference.java

@@ -26,6 +26,7 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.Set;
 
+import net.minecraft.init.Items;
 import net.minecraft.item.ItemStack;
 
 import appeng.api.storage.data.IAEItemStack;
@@ -54,7 +55,7 @@ public class OreReference
 			{
 				for( final ItemStack is : OreHelper.INSTANCE.getCachedOres( oreName ) )
 				{
-					if( is.getItem() != null )
+					if( is.getItem() != Items.AIR )
 					{
 						this.aeOtherOptions.add( AEItemStack.create( is ) );
 					}