Fixed NPE bugs in API by returning empty, rather than null, and updat…

…ed the method descriptions accordingly.

src/main/java/mod/chiselsandbits/api/IBitAccess.java

@@ -98,7 +98,7 @@ void commitChanges(
 	 *            or if it is portable, cross world NBT is larger and slower,
 	 *            you should only request cross world NBT if you specifically
 	 *            need it.
-	 * @return an Item for bits, null if there are no bits.
+	 * @return an Item for bits, which is empty if there are no bits.
 	 */
 	ItemStack getBitsAsItem(
 			EnumFacing side,
@@ -116,7 +116,7 @@ ItemStack getBitsAsItem(
 	 *            angle the player is looking at, can be null.
 	 * @param type
 	 *            what type of item to give.
-	 * @return an Item for bits, null if there are no bits.
+	 * @return an Item for bits, which is empty if there are no bits.
 	 */
 	@Deprecated
 	ItemStack getBitsAsItem(

src/main/java/mod/chiselsandbits/api/IBitBrush.java

@@ -25,16 +25,15 @@ public interface IBitBrush
 	IBlockState getState();
 
 	/**
-	 * Get the ItemStack for a bit, returns null for air.
+	 * Get the ItemStack for a bit, which is empty for air.
 	 *
 	 * VERY IMPORTANT: C&B lets you disable bits, if this happens the Item in
 	 * this ItemStack WILL BE NULL, if you put this item in an inventory, drop
 	 * it on the ground, or anything else.. CHECK THIS!!!!!
 	 *
 	 * @param count
-	 * @return ItemStack, or null for air.
+	 * @return ItemStack, which is empty for air.
 	 */
-	@Nullable
 	ItemStack getItemStack(
 			int count );
 

src/main/java/mod/chiselsandbits/core/api/BitAccess.java

@@ -140,13 +140,13 @@ public ItemStack getBitsAsItem(
 	{
 		if ( type == null )
 		{
-			return null;
+			return ModUtil.getEmptyStack();
 		}
 
 		final BlobStats cb = blob.getVoxelStats();
 		if ( cb.mostCommonState == 0 )
 		{
-			return null;
+			return ModUtil.getEmptyStack();
 		}
 
 		final NBTBlobConverter c = new NBTBlobConverter();
@@ -164,7 +164,7 @@ public ItemStack getBitsAsItem(
 
 			if ( blk == null )
 			{
-				return null;
+				return ModUtil.getEmptyStack();
 			}
 
 			itemstack = new ItemStack( blk, 1 );

src/main/java/mod/chiselsandbits/core/api/BitBrush.java

@@ -20,12 +20,12 @@ public BitBrush(
 	}
 
 	@Override
-	public @Nullable ItemStack getItemStack(
+	public ItemStack getItemStack(
 			final int count )
 	{
 		if ( stateID == 0 )
 		{
-			return null;
+			return ModUtil.getEmptyStack();
 		}
 
 		return ItemChiseledBit.createStack( stateID, count, true );