diff --git a/pom.xml b/pom.xml
index f7d86c3..c4063b2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -14,8 +14,8 @@
 
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
+        <maven.compiler.source>16</maven.compiler.source>
+        <maven.compiler.target>16</maven.compiler.target>
 	</properties>
 
 	<repositories>
@@ -33,7 +33,7 @@
 		<dependency>
 			<groupId>org.spigotmc</groupId>
 			<artifactId>spigot-api</artifactId>
-			<version>1.16.5-R0.1-SNAPSHOT</version>
+			<version>1.17.1-R0.1-SNAPSHOT</version>
 		</dependency>
 		<dependency>
 			<groupId>net.milkbowl.vault</groupId>
@@ -48,8 +48,8 @@
         </dependency>
         <dependency>
             <groupId>com.github.seeseemelk</groupId>
-            <artifactId>MockBukkit-v1.16</artifactId>
-            <version>0.24.0</version>
+            <artifactId>MockBukkit-v1.17</artifactId>
+            <version>1.7.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
@@ -58,6 +58,12 @@
             <version>19.0.0</version>
             <scope>compile</scope>
         </dependency>
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<version>4.13.1</version>
+			<scope>test</scope>
+		</dependency>
 	</dependencies>
 
 	<build>
diff --git a/src/main/java/net/knarcraft/stargate/RelativeBlockVector.java b/src/main/java/net/knarcraft/stargate/RelativeBlockVector.java
index 8bf2624..15c17ab 100644
--- a/src/main/java/net/knarcraft/stargate/RelativeBlockVector.java
+++ b/src/main/java/net/knarcraft/stargate/RelativeBlockVector.java
@@ -10,9 +10,9 @@ package net.knarcraft.stargate;
  */
 public class RelativeBlockVector {
 
-    private int right;
-    private int depth;
-    private int distance;
+    private final int right;
+    private final int depth;
+    private final int distance;
 
     /**
      * Instantiates a new relative block vector
diff --git a/src/main/java/net/knarcraft/stargate/Stargate.java b/src/main/java/net/knarcraft/stargate/Stargate.java
index 5037c61..23cfe82 100644
--- a/src/main/java/net/knarcraft/stargate/Stargate.java
+++ b/src/main/java/net/knarcraft/stargate/Stargate.java
@@ -6,7 +6,7 @@ import net.knarcraft.stargate.event.StargateAccessEvent;
 import net.knarcraft.stargate.listener.BlockEventListener;
 import net.knarcraft.stargate.listener.BungeeCordListener;
 import net.knarcraft.stargate.listener.EntityEventListener;
-import net.knarcraft.stargate.listener.PlayerEventsListener;
+import net.knarcraft.stargate.listener.PlayerEventListener;
 import net.knarcraft.stargate.listener.PluginEventListener;
 import net.knarcraft.stargate.listener.VehicleEventListener;
 import net.knarcraft.stargate.listener.WorldEventListener;
@@ -67,13 +67,13 @@ public class Stargate extends JavaPlugin {
     // Used for debug
     public static boolean debug = false;
     public static boolean permDebug = false;
-    public static ConcurrentLinkedQueue<Portal> activeList = new ConcurrentLinkedQueue<>();
+    public static final ConcurrentLinkedQueue<Portal> activeList = new ConcurrentLinkedQueue<>();
     // Used for populating gate open/closed material.
-    public static Queue<BloxPopulator> blockPopulatorQueue = new LinkedList<>();
+    public static final Queue<BloxPopulator> blockPopulatorQueue = new LinkedList<>();
     // HashMap of player names for Bungee support
-    public static Map<String, String> bungeeQueue = new HashMap<>();
+    public static final Map<String, String> bungeeQueue = new HashMap<>();
     // World names that contain stargates
-    public static HashSet<String> managedWorlds = new HashSet<>();
+    public static final HashSet<String> managedWorlds = new HashSet<>();
     private static String pluginVersion;
     private static String portalFolder;
     private static String gateFolder;
@@ -535,7 +535,7 @@ public class Stargate extends JavaPlugin {
         log.info(pluginDescriptionFile.getName() + " v." + pluginDescriptionFile.getVersion() + " is enabled.");
 
         // Register events before loading gates to stop weird things happening.
-        pm.registerEvents(new PlayerEventsListener(), this);
+        pm.registerEvents(new PlayerEventListener(), this);
         pm.registerEvents(new BlockEventListener(), this);
 
         pm.registerEvents(new VehicleEventListener(), this);
@@ -656,7 +656,7 @@ public class Stargate extends JavaPlugin {
         File newFile = new File(portalFolder, getServer().getWorlds().get(0).getName() + ".db");
         if (!newFile.exists()) {
             if (!newFile.getParentFile().mkdirs()) {
-                log.severe("Unable to create portal directory");
+                log.severe("Unable to create portal database folder: " + newFile.getParentFile().getPath());
             }
         }
     }
diff --git a/src/main/java/net/knarcraft/stargate/TwoTuple.java b/src/main/java/net/knarcraft/stargate/TwoTuple.java
index 6167fac..438590d 100644
--- a/src/main/java/net/knarcraft/stargate/TwoTuple.java
+++ b/src/main/java/net/knarcraft/stargate/TwoTuple.java
@@ -8,8 +8,8 @@ package net.knarcraft.stargate;
  */
 public class TwoTuple<K, L> {
 
-    private K firstValue;
-    private L secondValue;
+    private final K firstValue;
+    private final L secondValue;
 
     /**
      * Instantiate a new TwoTuple
diff --git a/src/main/java/net/knarcraft/stargate/command/CommandReload.java b/src/main/java/net/knarcraft/stargate/command/CommandReload.java
index 3147062..2d4ea4d 100644
--- a/src/main/java/net/knarcraft/stargate/command/CommandReload.java
+++ b/src/main/java/net/knarcraft/stargate/command/CommandReload.java
@@ -12,7 +12,7 @@ import org.jetbrains.annotations.NotNull;
  */
 public class CommandReload implements CommandExecutor {
 
-    private Stargate plugin;
+    private final Stargate plugin;
 
     /**
      * Instantiates the reload command
diff --git a/src/main/java/net/knarcraft/stargate/command/CommandStarGate.java b/src/main/java/net/knarcraft/stargate/command/CommandStarGate.java
index bcc86ab..182e4c8 100644
--- a/src/main/java/net/knarcraft/stargate/command/CommandStarGate.java
+++ b/src/main/java/net/knarcraft/stargate/command/CommandStarGate.java
@@ -15,7 +15,7 @@ import org.jetbrains.annotations.NotNull;
  */
 public class CommandStarGate implements CommandExecutor {
 
-    private Stargate plugin;
+    private final Stargate plugin;
 
     /**
      * Instantiates the stargate command
diff --git a/src/main/java/net/knarcraft/stargate/listener/BungeeCordListener.java b/src/main/java/net/knarcraft/stargate/listener/BungeeCordListener.java
index 700fda4..0d58dda 100644
--- a/src/main/java/net/knarcraft/stargate/listener/BungeeCordListener.java
+++ b/src/main/java/net/knarcraft/stargate/listener/BungeeCordListener.java
@@ -23,7 +23,7 @@ public class BungeeCordListener implements PluginMessageListener {
      * @param message <p>The message received from the plugin</p>
      */
     @Override
-    public void onPluginMessageReceived(@NotNull String channel, @NotNull Player unused, @NotNull byte[] message) {
+    public void onPluginMessageReceived(@NotNull String channel, @NotNull Player unused, byte[] message) {
         //Ignore plugin messages if bungee support is not enabled or some other plugin message is received
         if (!Stargate.enableBungee || !channel.equals("BungeeCord")) {
             return;
diff --git a/src/main/java/net/knarcraft/stargate/listener/PlayerEventsListener.java b/src/main/java/net/knarcraft/stargate/listener/PlayerEventListener.java
similarity index 98%
rename from src/main/java/net/knarcraft/stargate/listener/PlayerEventsListener.java
rename to src/main/java/net/knarcraft/stargate/listener/PlayerEventListener.java
index 108470a..298464a 100644
--- a/src/main/java/net/knarcraft/stargate/listener/PlayerEventsListener.java
+++ b/src/main/java/net/knarcraft/stargate/listener/PlayerEventListener.java
@@ -31,7 +31,7 @@ import java.util.Objects;
  * This listener listens to any player-related events related to stargates
  */
 @SuppressWarnings("unused")
-public class PlayerEventsListener implements Listener {
+public class PlayerEventListener implements Listener {
 
     private static long eventTime;
     private static PlayerInteractEvent previousEvent;
@@ -208,10 +208,7 @@ public class PlayerEventsListener implements Listener {
      * @return <p>True if the player should be denied</p>
      */
     private boolean cannotAccessPortal(Player player, Portal portal) {
-        boolean deny = false;
-        if (!Stargate.canAccessNetwork(player, portal.getNetwork())) {
-            deny = true;
-        }
+        boolean deny = !Stargate.canAccessNetwork(player, portal.getNetwork());
 
         if (!Stargate.canAccessPortal(player, portal, deny)) {
             Stargate.sendMessage(player, Stargate.getString("denyMsg"));
diff --git a/src/main/java/net/knarcraft/stargate/portal/Gate.java b/src/main/java/net/knarcraft/stargate/portal/Gate.java
index cd1afb4..3f43583 100644
--- a/src/main/java/net/knarcraft/stargate/portal/Gate.java
+++ b/src/main/java/net/knarcraft/stargate/portal/Gate.java
@@ -28,13 +28,13 @@ public class Gate {
     //Gate materials
     private Material portalOpenBlock;
     private Material portalClosedBlock;
-    private Material portalButton;
+    private final Material portalButton;
 
     // Economy information
-    private int useCost;
-    private int createCost;
-    private int destroyCost;
-    private boolean toOwner;
+    private final int useCost;
+    private final int createCost;
+    private final int destroyCost;
+    private final boolean toOwner;
 
     /**
      * Instantiates a new gate
diff --git a/src/main/java/net/knarcraft/stargate/portal/GateHandler.java b/src/main/java/net/knarcraft/stargate/portal/GateHandler.java
index 1e47965..2840f6d 100644
--- a/src/main/java/net/knarcraft/stargate/portal/GateHandler.java
+++ b/src/main/java/net/knarcraft/stargate/portal/GateHandler.java
@@ -25,9 +25,9 @@ public class GateHandler {
     private static final Character EXIT = '*';
     private static final Character CONTROL_BLOCK = '-';
 
-    private static Material defaultPortalBlockOpen = Material.NETHER_PORTAL;
-    private static Material defaultPortalBlockClosed = Material.AIR;
-    private static Material defaultButton = Material.STONE_BUTTON;
+    private static final Material defaultPortalBlockOpen = Material.NETHER_PORTAL;
+    private static final Material defaultPortalBlockClosed = Material.AIR;
+    private static final Material defaultButton = Material.STONE_BUTTON;
 
     private static final HashMap<String, Gate> gates = new HashMap<>();
     private static final HashMap<Material, List<Gate>> controlBlocks = new HashMap<>();
@@ -162,7 +162,7 @@ public class GateHandler {
         int useCost = readConfig(config, fileName, "usecost", -1);
         int createCost = readConfig(config, fileName, "createcost", -1);
         int destroyCost = readConfig(config, fileName, "destroycost", -1);
-        boolean toOwner = (config.containsKey("toowner") ? Boolean.valueOf(config.get("toowner")) : EconomyHandler.toOwner);
+        boolean toOwner = (config.containsKey("toowner") ? Boolean.parseBoolean(config.get("toowner")) : EconomyHandler.toOwner);
 
         Gate gate = new Gate(fileName, new GateLayout(layout), types, portalOpenBlock, portalClosedBlock, portalButton, useCost,
                 createCost, destroyCost, toOwner);
diff --git a/src/main/java/net/knarcraft/stargate/portal/GateLayout.java b/src/main/java/net/knarcraft/stargate/portal/GateLayout.java
index c0a103f..61e31a3 100644
--- a/src/main/java/net/knarcraft/stargate/portal/GateLayout.java
+++ b/src/main/java/net/knarcraft/stargate/portal/GateLayout.java
@@ -16,7 +16,7 @@ import java.util.List;
  */
 public class GateLayout {
 
-    private Character [][] layout;
+    private final Character [][] layout;
     private final List<RelativeBlockVector> exits = new ArrayList<>();
     private RelativeBlockVector[] entrances = new RelativeBlockVector[0];
     private RelativeBlockVector[] border = new RelativeBlockVector[0];
diff --git a/src/main/java/net/knarcraft/stargate/portal/Portal.java b/src/main/java/net/knarcraft/stargate/portal/Portal.java
index 2b816d8..ba44784 100644
--- a/src/main/java/net/knarcraft/stargate/portal/Portal.java
+++ b/src/main/java/net/knarcraft/stargate/portal/Portal.java
@@ -64,11 +64,11 @@ public class Portal {
     private String destination;
     private String lastDestination = "";
     private String network;
-    private String ownerName;
+    private final String ownerName;
     private UUID ownerUUID;
     private boolean verified;
     private boolean fixed;
-    private Map<PortalOption, Boolean> options;
+    private final Map<PortalOption, Boolean> options;
 
     // In-use information
     private Player player;
diff --git a/src/main/java/net/knarcraft/stargate/portal/PortalHandler.java b/src/main/java/net/knarcraft/stargate/portal/PortalHandler.java
index d3b420e..cb61cbd 100644
--- a/src/main/java/net/knarcraft/stargate/portal/PortalHandler.java
+++ b/src/main/java/net/knarcraft/stargate/portal/PortalHandler.java
@@ -931,7 +931,7 @@ public class PortalHandler {
             }
         }
         PortalHandler.unregisterPortal(portal, false);
-        Stargate.log.info(Stargate.getString("prefix") + "Destroying stargate at " + portal.toString());
+        Stargate.log.info(Stargate.getString("prefix") + "Destroying stargate at " + portal);
     }
 
     /**