Adds a new StargateTeleportEvent to combine some duplicated code

src/main/java/net/knarcraft/stargate/event/StargateEntityPortalEvent.java

@@ -12,7 +12,7 @@ import org.jetbrains.annotations.NotNull;
  * <p>This event can be used to overwrite the location the entity is teleported to.</p>
  */
 @SuppressWarnings("unused")
-public class StargateEntityPortalEvent extends StargateEvent {
+public class StargateEntityPortalEvent extends StargateEvent implements StargateTeleportEvent {
 
     private static final HandlerList handlers = new HandlerList();
     final Entity travellingEntity;
@@ -58,6 +58,7 @@ public class StargateEntityPortalEvent extends StargateEvent {
      *
      * @return <p>Location of the exit point</p>
      */
+    @Override
     public Location getExit() {
         return exit;
     }

src/main/java/net/knarcraft/stargate/event/StargatePlayerPortalEvent.java

@@ -12,7 +12,7 @@ import org.jetbrains.annotations.NotNull;
  * <p>This event can be used to overwrite the location the player is teleported to.</p>
  */
 @SuppressWarnings("unused")
-public class StargatePlayerPortalEvent extends StargatePlayerEvent {
+public class StargatePlayerPortalEvent extends StargatePlayerEvent implements StargateTeleportEvent {
 
     private static final HandlerList handlers = new HandlerList();
     private final Portal destination;
@@ -47,6 +47,7 @@ public class StargatePlayerPortalEvent extends StargatePlayerEvent {
      *
      * @return <p>Location of the exit point</p>
      */
+    @Override
     public Location getExit() {
         return exit;
     }

src/main/java/net/knarcraft/stargate/event/StargateTeleportEvent.java

@@ -0,0 +1,18 @@
+package net.knarcraft.stargate.event;
+
+import org.bukkit.Location;
+import org.bukkit.event.Cancellable;
+
+/**
+ * A generic teleportation event
+ */
+public interface StargateTeleportEvent extends Cancellable {
+
+    /**
+     * Return the location of the players exit point
+     *
+     * @return <p>Location of the exit point</p>
+     */
+    Location getExit();
+
+}