Even more null fixes.

src/main/java/appeng/block/storage/BlockChest.java

@@ -109,7 +109,7 @@ public class BlockChest extends AEBaseTileBlock
 			else
 			{
 				final ItemStack cell = tg.getStackInSlot( 1 );
-				if( cell != null )
+				if( !cell.isEmpty() )
 				{
 					final ICellHandler ch = AEApi.instance().registries().cell().getHandler( cell );
 

src/main/java/appeng/integration/modules/jei/JEIPlugin.java

@@ -128,7 +128,7 @@ public class JEIPlugin extends BlankModPlugin
 
 		ItemStack grindstone = definitions.blocks().grindstone().maybeStack( 1 ).orElse( ItemStack.EMPTY );
 
-		if( grindstone == null )
+		if( grindstone.isEmpty() )
 		{
 			return;
 		}
@@ -143,24 +143,24 @@ public class JEIPlugin extends BlankModPlugin
 	{
 
 		ItemStack condenser = definitions.blocks().condenser().maybeStack( 1 ).orElse( ItemStack.EMPTY );
-		if( condenser == null )
+		if( condenser.isEmpty() )
 		{
 			return;
 		}
 
 		ItemStack matterBall = definitions.materials().matterBall().maybeStack( 1 ).orElse( ItemStack.EMPTY );
-		if( matterBall != null )
+		if( !matterBall.isEmpty() )
 		{
 			registry.addRecipes( ImmutableList.of( CondenserOutput.MATTER_BALLS ) );
 		}
 
 		ItemStack singularity = definitions.materials().singularity().maybeStack( 1 ).orElse( ItemStack.EMPTY );
-		if( singularity != null )
+		if( !singularity.isEmpty() )
 		{
 			registry.addRecipes( ImmutableList.of( CondenserOutput.SINGULARITY ) );
 		}
 
-		if( matterBall != null || singularity != null )
+		if( !matterBall.isEmpty() || !singularity.isEmpty() )
 		{
 			registry.addRecipeCategories( new CondenserCategory( registry.getJeiHelpers().getGuiHelper() ) );
 			registry.addRecipeCategoryCraftingItem( condenser, CondenserCategory.UID );

src/main/java/appeng/parts/p2p/PartP2PTunnel.java

@@ -261,11 +261,11 @@ public abstract class PartP2PTunnel<T extends PartP2PTunnel> extends PartBasicSt
 				 */
 
 				default:
-					newType = null;
+					newType = ItemStack.EMPTY;
 					break;
 			}
 
-			if( newType != null && !Platform.itemComparisons().isEqualItem( newType, this.getItemStack() ) )
+			if( !newType.isEmpty() && !Platform.itemComparisons().isEqualItem( newType, this.getItemStack() ) )
 			{
 				final boolean oldOutput = this.isOutput();
 				final long myFreq = this.getFrequency();

src/main/java/appeng/tile/storage/TileChest.java

@@ -108,7 +108,7 @@ public class TileChest extends AENetworkPowerTile implements IMEChest, ITerminal
 	private final AppEngInternalInventory inv = new AppEngInternalInventory( this, 2 );
 	private final BaseActionSource mySrc = new MachineSource( this );
 	private final IConfigManager config = new ConfigManager( this );
-	private ItemStack storageType;
+	private ItemStack storageType = ItemStack.EMPTY;
 	private long lastStateChange = 0;
 	private int priority = 0;
 	private int state = 0;

src/main/java/appeng/tile/storage/TileIOPort.java

@@ -242,7 +242,7 @@ public class TileIOPort extends AENetworkInvTile implements IUpgradeableHost, IC
 		{
 			for( int x = 0; x < 6; x++ )
 			{
-				if( this.cells.getStackInSlot( x ) != null )
+				if( !this.cells.getStackInSlot( x ).isEmpty() )
 				{
 					return true;
 				}
@@ -572,7 +572,7 @@ public class TileIOPort extends AENetworkInvTile implements IUpgradeableHost, IC
 		{
 			final ItemStack stackInSlot = this.upgrades.getStackInSlot( upgradeIndex );
 
-			if( stackInSlot != null )
+			if( !stackInSlot.isEmpty() )
 			{
 				drops.add( stackInSlot );
 			}