Starting on cleaning up null checks & type casting

src/main/java/com/gmail/nossr50/skills/acrobatics/Acrobatics.java

@@ -5,7 +5,9 @@ import java.util.Random;
 import com.gmail.nossr50.config.AdvancedConfig;
 
 public class Acrobatics {
-    static AdvancedConfig advancedConfig = AdvancedConfig.getInstance();
+    private static AdvancedConfig advancedConfig = AdvancedConfig.getInstance();
+    private static Random random = new Random();
+
     public static final int DODGE_MAX_CHANCE = advancedConfig.getDodgeChanceMax();
     public static final int DODGE_MAX_BONUS_LEVEL = advancedConfig.getDodgeMaxBonusLevel();
     public static final int DODGE_XP_MODIFIER = advancedConfig.getDodgeXPModifier();
@@ -18,9 +20,7 @@ public class Acrobatics {
     public static final int ROLL_XP_MODIFIER = advancedConfig.getRollXPModifier();
     public static final int FALL_XP_MODIFIER = advancedConfig.getFallXPModifier();
 
-    private static Random random = new Random();
+    protected static Random getRandom() {
-
-    public static Random getRandom() {
         return random;
     }
 }

src/main/java/com/gmail/nossr50/skills/acrobatics/AcrobaticsEventHandler.java

@@ -3,6 +3,8 @@ package com.gmail.nossr50.skills.acrobatics;
 import org.bukkit.entity.Player;
 import org.bukkit.event.entity.EntityDamageEvent;
 
+import com.gmail.nossr50.util.Misc;
+
 public abstract class AcrobaticsEventHandler {
     protected AcrobaticsManager manager;
     protected Player player;
@@ -51,14 +53,10 @@ public abstract class AcrobaticsEventHandler {
      * @return true if the damage is fatal, false otherwise
      */
     protected boolean isFatal(int damage) {
-        if(player == null)
+        if (Misc.isCitizensNPC(player) || player.getHealth() - damage < 1) {
-            return true;
-
-        if (player.getHealth() - damage < 1) {
             return true;
         }
-        else {
+
         return false;
     }
-    }
 }

src/main/java/com/gmail/nossr50/skills/acrobatics/AcrobaticsManager.java

@@ -6,10 +6,13 @@ import org.bukkit.event.entity.EntityDamageEvent;
 import com.gmail.nossr50.config.Config;
 import com.gmail.nossr50.datatypes.PlayerProfile;
 import com.gmail.nossr50.datatypes.SkillType;
+import com.gmail.nossr50.util.Misc;
 import com.gmail.nossr50.util.Permissions;
 import com.gmail.nossr50.util.Users;
 
 public class AcrobaticsManager {
+    private static Config config = Config.getInstance();
+
     private Player player;
     private PlayerProfile profile;
     private int skillLevel;
@@ -26,29 +29,28 @@ public class AcrobaticsManager {
      * @param event The event to check
      */
     public void rollCheck(EntityDamageEvent event) {
-        if(player == null)
+        if (Misc.isCitizensNPC(player) || !Permissions.roll(player)) {
-            return;
-
-        if (!Permissions.roll(player)) {
             return;
         }
 
-        if(Config.getInstance().getAcrobaticsAFKDisabled() && player.isInsideVehicle())
+        if (config.getAcrobaticsAFKDisabled() && player.isInsideVehicle()) {
             return;
+        }
 
         RollEventHandler eventHandler = new RollEventHandler(this, event);
 
         int randomChance = 100;
-
         if (Permissions.luckyAcrobatics(player)) {
             randomChance = (int) (randomChance * 0.75);
         }
 
-        float chance = (float) (((double) Acrobatics.ROLL_MAX_CHANCE / (double) Acrobatics.ROLL_MAX_BONUS_LEVEL) * skillLevel);
+        float chance;
-        if (chance > Acrobatics.ROLL_MAX_CHANCE) chance = Acrobatics.ROLL_MAX_CHANCE;
+
         if (eventHandler.isGraceful) {
-        	chance = (float) (((double) Acrobatics.GRACEFUL_MAX_CHANCE / (double) Acrobatics.GRACEFUL_MAX_BONUS_LEVEL) * skillLevel);
+            chance = ((float) Acrobatics.GRACEFUL_MAX_CHANCE / Acrobatics.GRACEFUL_MAX_BONUS_LEVEL) * eventHandler.skillModifier;
-        	if (chance > Acrobatics.GRACEFUL_MAX_CHANCE) chance = Acrobatics.GRACEFUL_MAX_CHANCE;
+        }
+        else {
+            chance = ((float) Acrobatics.ROLL_MAX_CHANCE / Acrobatics.ROLL_MAX_BONUS_LEVEL) * eventHandler.skillModifier;
         }
 
         if (chance > Acrobatics.getRandom().nextInt(randomChance) && !eventHandler.isFatal(eventHandler.modifiedDamage)) {
@@ -67,23 +69,18 @@ public class AcrobaticsManager {
      * @param event The event to check
      */
     public void dodgeCheck(EntityDamageEvent event) {
-        if(player == null)
+        if (Misc.isCitizensNPC(player) || !Permissions.dodge(player)) {
-            return;
-
-        if (!Permissions.dodge(player)) {
             return;
         }
 
         DodgeEventHandler eventHandler = new DodgeEventHandler(this, event);
 
         int randomChance = 100;
-
         if (Permissions.luckyAcrobatics(player)) {
             randomChance = (int) (randomChance * 0.75);
         }
 
-        float chance = (float) (((double) Acrobatics.DODGE_MAX_CHANCE / (double) Acrobatics.DODGE_MAX_BONUS_LEVEL) * skillLevel);
+        float chance = ((float) Acrobatics.DODGE_MAX_CHANCE / Acrobatics.DODGE_MAX_BONUS_LEVEL) * eventHandler.skillModifier;
-        if (chance > Acrobatics.DODGE_MAX_CHANCE) chance = Acrobatics.DODGE_MAX_CHANCE;
 
         if (chance > Acrobatics.getRandom().nextInt(randomChance) && !eventHandler.isFatal(eventHandler.modifiedDamage)) {
             eventHandler.modifyEventDamage();

src/main/java/com/gmail/nossr50/skills/acrobatics/DodgeEventHandler.java

@@ -39,20 +39,14 @@ public class DodgeEventHandler extends AcrobaticsEventHandler {
 
     @Override
     protected void sendAbilityMessage() {
-        if(player == null)
-            return;
-
         player.sendMessage(LocaleLoader.getString("Acrobatics.Combat.Proc"));
     }
 
     @Override
     protected void processXPGain(int xp) {
-        if(player == null)
-            return;
-
         PlayerProfile profile = manager.getProfile();
 
-        if (System.currentTimeMillis() >= profile.getRespawnATS() + 5) {
+        if (System.currentTimeMillis() >= profile.getRespawnATS() + Misc.PLAYER_RESPAWN_COOLDOWN_SECONDS) {
             Skills.xpProcessing(player, profile, SkillType.ACROBATICS, xp);
         }
     }

src/main/java/com/gmail/nossr50/skills/acrobatics/RollEventHandler.java

@@ -56,9 +56,6 @@ public class RollEventHandler extends AcrobaticsEventHandler {
 
     @Override
     protected void sendAbilityMessage() {
-        if(player == null)
-            return;
-
         if (isGraceful) {
             player.sendMessage(LocaleLoader.getString("Acrobatics.Ability.Proc"));
         }
@@ -70,9 +67,6 @@ public class RollEventHandler extends AcrobaticsEventHandler {
 
     @Override
     protected void processXPGain(int xpGain) {
-        if(player == null)
-            return;
-
         Skills.xpProcessing(player, manager.getProfile(), SkillType.ACROBATICS, xpGain);
     }
 
@@ -80,9 +74,6 @@ public class RollEventHandler extends AcrobaticsEventHandler {
      * Check if this is a graceful roll.
      */
     private void isGracefulRoll() {
-        if(player == null)
-            return;
-
         if (Permissions.gracefulRoll(player)) {
             this.isGraceful = player.isSneaking();
         }

src/main/java/com/gmail/nossr50/skills/mining/MiningManager.java

@@ -63,8 +63,7 @@ public class MiningManager {
             return;
         }
 
-        MiningManager manager = new MiningManager(player);
+        SuperBreakerEventHandler eventHandler = new SuperBreakerEventHandler(this, block);
-        SuperBreakerEventHandler eventHandler = new SuperBreakerEventHandler(manager, block);
 
         if (eventHandler.tierCheck()) {
             return;

src/main/java/com/gmail/nossr50/util/Misc.java

@@ -23,6 +23,11 @@ public class Misc {
     private static Random random = new Random();
 
     public static final int TOOL_DURABILITY_LOSS = Config.getInstance().getAbilityToolDamage();
+    public static final int PLAYER_RESPAWN_COOLDOWN_SECONDS = 5;
+
+    public static boolean isCitizensNPC(Player player) {
+        return player.hasMetadata("NPC");
+    }
 
     /**
      * Gets a capitalized version of the target string.