Finalize fields where possible (#1021)

src/main/java/me/ryanhamshire/GriefPrevention/events/AccrueClaimBlocksEvent.java

@@ -26,7 +26,7 @@ public class AccrueClaimBlocksEvent extends Event
         return handlers;
     }
 
-    private Player player;
+    private final Player player;
     private int blocksToAccrue;
     private boolean isIdle = false;
     private boolean cancelled = false;

src/main/java/me/ryanhamshire/GriefPrevention/events/ClaimDeletedEvent.java

@@ -21,7 +21,7 @@ public class ClaimDeletedEvent extends Event
         return handlers;
     }
 
-    private Claim claim;
+    private final Claim claim;
 
     public ClaimDeletedEvent(Claim claim)
     {

src/main/java/me/ryanhamshire/GriefPrevention/events/ClaimModifiedEvent.java

@@ -24,7 +24,7 @@ public class ClaimModifiedEvent extends Event implements Cancellable
 
     private final Claim from;
     private final Claim to;
-    private CommandSender modifier;
+    private final CommandSender modifier;
     private boolean cancelled;
 
     public ClaimModifiedEvent(Claim from, Claim to, CommandSender modifier)

src/main/java/me/ryanhamshire/GriefPrevention/events/PlayerKickBanEvent.java

@@ -25,10 +25,10 @@ public class PlayerKickBanEvent extends Event
         return handlers;
     }
 
-    private Player player;
-    private String reason;
-    private String source;
-    private boolean ban;
+    private final Player player;
+    private final String reason;
+    private final String source;
+    private final boolean ban;
     private boolean cancelled = false;
 
     /**

src/main/java/me/ryanhamshire/GriefPrevention/events/PreventBlockBreakEvent.java

@@ -10,7 +10,7 @@ public class PreventBlockBreakEvent extends Event implements Cancellable
 {
     private static final HandlerList handlers = new HandlerList();
     private boolean cancelled = false;
-    private BlockBreakEvent innerEvent;
+    private final BlockBreakEvent innerEvent;
 
     public static HandlerList getHandlerList()
     {