make the specimen slot work and some small improvements

src/main/java/storagecraft/container/ContainerDrive.java

@@ -2,7 +2,7 @@ package storagecraft.container;
 
 import net.minecraft.entity.player.EntityPlayer;
 import storagecraft.SCItems;
-import storagecraft.inventory.slot.SlotItemFilter;
+import storagecraft.container.slot.SlotItemFilter;
 import storagecraft.tile.TileDrive;
 
 public class ContainerDrive extends ContainerSC {

src/main/java/storagecraft/container/ContainerImporter.java

@@ -1,7 +1,7 @@
 package storagecraft.container;
 
 import net.minecraft.entity.player.EntityPlayer;
-import storagecraft.inventory.slot.SlotSpecimen;
+import storagecraft.container.slot.SlotSpecimen;
 import storagecraft.tile.TileImporter;
 
 public class ContainerImporter extends ContainerSC {

src/main/java/storagecraft/container/ContainerSC.java

@@ -4,6 +4,7 @@ import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.inventory.Container;
 import net.minecraft.inventory.Slot;
 import net.minecraft.item.ItemStack;
+import storagecraft.container.slot.SlotSpecimen;
 
 public class ContainerSC extends Container {
 	private EntityPlayer player;
@@ -34,6 +35,23 @@ public class ContainerSC extends Container {
 		}
 	}
 
+	@Override
+	public ItemStack slotClick(int id, int clickedButton, int mode, EntityPlayer player) {
+		Slot slot = id >= 0 ? getSlot(id) : null;
+
+		if (slot instanceof SlotSpecimen) {
+			if (clickedButton == 2) {
+				slot.putStack(null);
+			} else {
+				slot.putStack(player.inventory.getItemStack() == null ? null : player.inventory.getItemStack().copy());
+			}
+
+			return player.inventory.getItemStack();
+		}
+
+		return super.slotClick(id, clickedButton, mode, player);
+	}
+
 	@Override
 	public ItemStack transferStackInSlot(EntityPlayer player, int slotIndex) {
 		return null;

src/main/java/storagecraft/container/slot/SlotItemFilter.java

@@ -0,0 +1,21 @@
+package storagecraft.container.slot;
+
+import net.minecraft.inventory.IInventory;
+import net.minecraft.inventory.Slot;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
+
+public class SlotItemFilter extends Slot {
+	private Item item;
+
+	public SlotItemFilter(IInventory inventory, int id, int x, int y, Item item) {
+		super(inventory, id, x, y);
+
+		this.item = item;
+	}
+
+	@Override
+	public boolean isItemValid(ItemStack item) {
+		return item.getItem() == this.item;
+	}
+}

src/main/java/storagecraft/container/slot/SlotSpecimen.java

@@ -0,0 +1,31 @@
+package storagecraft.container.slot;
+
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.inventory.IInventory;
+import net.minecraft.inventory.Slot;
+import net.minecraft.item.ItemStack;
+
+public class SlotSpecimen extends Slot {
+	public SlotSpecimen(IInventory inventory, int id, int x, int y) {
+		super(inventory, id, x, y);
+	}
+
+	@Override
+	public boolean canTakeStack(EntityPlayer player) {
+		return false;
+	}
+
+	@Override
+	public boolean isItemValid(ItemStack stack) {
+		return true;
+	}
+
+	@Override
+	public void putStack(ItemStack stack) {
+		if (stack != null) {
+			stack.stackSize = 1;
+		}
+
+		super.putStack(stack);
+	}
+}