Make fields final if possible to ensure immutability

src/main/java/appeng/container/slot/AppEngCraftingSlot.java

@@ -21,7 +21,7 @@ public class AppEngCraftingSlot extends AppEngSlot
 	private final IInventory craftMatrix;
 
 	/** The player that is using the GUI where this slot resides. */
-	private EntityPlayer thePlayer;
+	private final EntityPlayer thePlayer;
 
 	/**
 	 * The number of items that have been crafted so far. Gets passed to ItemStack.onCrafting before being reset.

src/main/java/appeng/container/slot/AppEngSlot.java

@@ -33,7 +33,8 @@ public class AppEngSlot extends Slot
 
 	public int IIcon = -1;
 	public hasCalculatedValidness isValid;
-	public int defX, defY;
+	public final int defX;
+	public final int defY;
 
 	@Override
 	public boolean func_111238_b()

src/main/java/appeng/container/slot/OptionalSlotFake.java

@@ -6,14 +6,14 @@ import net.minecraft.item.ItemStack;
 public class OptionalSlotFake extends SlotFake
 {
 
-	int invSlot;
+	final int invSlot;
 	final int groupNum;
-	IOptionalSlotHost host;
+	final IOptionalSlotHost host;
 
 	public boolean renderDisabled = true;
 
-	public int srcX;
-	public int srcY;
+	public final int srcX;
+	public final int srcY;
 
 	public OptionalSlotFake(IInventory inv, IOptionalSlotHost containerBus, int idx, int x, int y, int offX, int offY, int groupNum) {
 		super( inv, idx, x + offX * 18, y + offY * 18 );

src/main/java/appeng/container/slot/OptionalSlotNormal.java

@@ -6,7 +6,7 @@ public class OptionalSlotNormal extends AppEngSlot
 {
 
 	final int groupNum;
-	IOptionalSlotHost host;
+	final IOptionalSlotHost host;
 
 	public OptionalSlotNormal(IInventory inv, IOptionalSlotHost containerBus, int slot, int xPos, int yPos, int groupNum) {
 		super( inv, slot, xPos, yPos );

src/main/java/appeng/container/slot/OptionalSlotRestrictedInput.java

@@ -7,7 +7,7 @@ public class OptionalSlotRestrictedInput extends SlotRestrictedInput
 {
 
 	final int groupNum;
-	IOptionalSlotHost host;
+	final IOptionalSlotHost host;
 
 	public OptionalSlotRestrictedInput(PlacableItemType valid, IInventory i, IOptionalSlotHost host, int slotIndex, int x, int y, int grpNum,
 			InventoryPlayer invPlayer) {

src/main/java/appeng/container/slot/SlotCraftingMatrix.java

@@ -7,7 +7,7 @@ import net.minecraft.item.ItemStack;
 public class SlotCraftingMatrix extends AppEngSlot
 {
 
-	Container c;
+	final Container c;
 
 	public SlotCraftingMatrix(Container c, IInventory par1iInventory, int par2, int par3, int par4) {
 		super( par1iInventory, par2, par3, par4 );

src/main/java/appeng/container/slot/SlotFake.java

@@ -7,7 +7,7 @@ import net.minecraft.item.ItemStack;
 public class SlotFake extends AppEngSlot
 {
 
-	int invSlot;
+	final int invSlot;
 
 	public SlotFake(IInventory inv, int idx, int x, int y) {
 		super( inv, idx, x, y );

src/main/java/appeng/container/slot/SlotMACPattern.java

@@ -7,7 +7,7 @@ import appeng.container.implementations.ContainerMAC;
 public class SlotMACPattern extends AppEngSlot
 {
 
-	ContainerMAC mac;
+	final ContainerMAC mac;
 
 	public SlotMACPattern(ContainerMAC mac, IInventory i, int slotIdx, int x, int y) {
 		super( i, slotIdx, x, y );

src/main/java/appeng/container/slot/SlotPatternTerm.java

@@ -16,8 +16,8 @@ import appeng.helpers.IContainerCraftingPacket;
 public class SlotPatternTerm extends SlotCraftingTerm
 {
 
-	int groupNum;
-	IOptionalSlotHost host;
+	final int groupNum;
+	final IOptionalSlotHost host;
 
 	public SlotPatternTerm(EntityPlayer player, BaseActionSource mySrc, IEnergySource energySrc, IStorageMonitorable storage, IInventory cMatrix,
 			IInventory secondMatrix, IInventory output, int x, int y, IOptionalSlotHost h, int groupNumber, IContainerCraftingPacket c)

src/main/java/appeng/container/slot/SlotRestrictedInput.java

@@ -68,10 +68,10 @@ public class SlotRestrictedInput extends AppEngSlot
 		return true;
 	}
 
-	public PlacableItemType which;
+	public final PlacableItemType which;
 	public boolean allowEdit = true;
 	public int stackLimit = -1;
-	private InventoryPlayer p;
+	private final InventoryPlayer p;
 
 	@Override
 	public boolean canTakeStack(EntityPlayer par1EntityPlayer)