API: add ClaimTransferEvent (#1641)

src/main/java/me/ryanhamshire/GriefPrevention/DataStore.java

@@ -23,6 +23,7 @@ import me.ryanhamshire.GriefPrevention.events.ClaimCreatedEvent;
 import me.ryanhamshire.GriefPrevention.events.ClaimDeletedEvent;
 import me.ryanhamshire.GriefPrevention.events.ClaimExtendEvent;
 import me.ryanhamshire.GriefPrevention.events.ClaimModifiedEvent;
+import me.ryanhamshire.GriefPrevention.events.ClaimTransferEvent;
 import org.bukkit.Bukkit;
 import org.bukkit.ChatColor;
 import org.bukkit.Chunk;
@@ -410,16 +411,23 @@ public abstract class DataStore
             ownerData = this.getPlayerData(claim.ownerID);
         }
 
+        //call event
+        ClaimTransferEvent event = new ClaimTransferEvent(claim, newOwnerID);
+        Bukkit.getPluginManager().callEvent(event);
+
+        //return if event is cancelled
+        if (event.isCancelled()) return;
+
         //determine new owner
         PlayerData newOwnerData = null;
 
-        if (newOwnerID != null)
+        if (event.getNewOwner() != null)
         {
-            newOwnerData = this.getPlayerData(newOwnerID);
+            newOwnerData = this.getPlayerData(event.getNewOwner());
         }
 
         //transfer
-        claim.ownerID = newOwnerID;
+        claim.ownerID = event.getNewOwner();
         this.saveClaim(claim);
 
         //adjust blocks and other records

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

@@ -0,0 +1,84 @@
+package me.ryanhamshire.GriefPrevention.events;
+
+import me.ryanhamshire.GriefPrevention.Claim;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.Event;
+import org.bukkit.event.HandlerList;
+
+import java.util.UUID;
+
+/**
+ * This Event is thrown when a claim is being transferred. If it is cancelled the claim will not be transferred.
+ * <p>
+ * Created by bertek41 on 30/10/2021.
+ */
+
+public class ClaimTransferEvent extends Event implements Cancellable
+{
+
+    private static final HandlerList handlers = new HandlerList();
+
+    public static HandlerList getHandlerList()
+    {
+        return handlers;
+    }
+
+    private final Claim claim;
+
+    private UUID newOwner;
+
+    private boolean cancelled = false;
+
+    public ClaimTransferEvent(Claim claim, UUID newOwner) {
+        this.claim = claim;
+        this.newOwner = newOwner;
+    }
+
+    @Override
+    public HandlerList getHandlers()
+    {
+        return handlers;
+    }
+
+    @Override
+    public boolean isCancelled()
+    {
+        return cancelled;
+    }
+
+    @Override
+    public void setCancelled(boolean cancelled)
+    {
+        this.cancelled = cancelled;
+    }
+
+    /**
+     * The Claim
+     *
+     * @return {@link Claim}
+     */
+    public Claim getClaim()
+    {
+        return claim;
+    }
+
+    /**
+     * New owner of the claim
+     *
+     * @return the {@link java.util.UUID} of new owner or null
+     */
+    public UUID getNewOwner()
+    {
+        return newOwner;
+    }
+
+    /**
+     * Sets the new owner of the claim
+     *
+     * @param {@link java.util.UUID} newOwner can be null
+     */
+    public void setNewOwner(UUID newOwner)
+    {
+        this.newOwner = newOwner;
+    }
+}