Forcibly disconnect players even if no server target was set in the JavaTransferEvent

api/src/main/java/org/geysermc/geyser/api/event/java/ServerTransferEvent.java

@@ -26,15 +26,22 @@
 package org.geysermc.geyser.api.event.java;
 
 import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.common.value.qual.IntRange;
 import org.geysermc.geyser.api.connection.GeyserConnection;
 import org.geysermc.geyser.api.event.connection.ConnectionEvent;
 
 import java.util.Map;
 
+/**
+ * Fired when the Java server sends a transfer request to a different Java server.
+ * Geyser Extensions can listen to this event and set a target server ip/port for Bedrock players to be transferred to.
+ */
 public class ServerTransferEvent extends ConnectionEvent {
 
     private final String host;
     private final int port;
+    private String bedrockHost;
+    private int bedrockPort;
     private final Map<String, byte[]> cookies;
 
     public ServerTransferEvent(@NonNull GeyserConnection connection, String host, int port, Map<String, byte[]> cookies) {
@@ -42,10 +49,13 @@ public class ServerTransferEvent extends ConnectionEvent {
         this.host = host;
         this.port = port;
         this.cookies = cookies;
+        this.bedrockHost = null;
+        this.bedrockPort = -1;
     }
 
     /**
      * The host that the Java server requests a transfer to.
+     *
      * @return the host
      */
     public String host() {
@@ -54,14 +64,56 @@ public class ServerTransferEvent extends ConnectionEvent {
 
     /**
      * The port that the Java server requests a transfer to.
+     *
      * @return the port
      */
     public int port() {
         return this.port;
     }
 
+    /**
+     * The host that the Bedrock player should try and connect to.
+     * If this is not set, the Bedrock player will just be disconnected.
+     *
+     * @return the host where the Bedrock client will be transferred to, or null if not set.
+     */
+    public String bedrockHost() {
+        return this.bedrockHost;
+    }
+
+    /**
+     * The port that the Bedrock player should try and connect to.
+     * If this is not set, the Bedrock player will just be disconnected.
+     *
+     * @return the port where the Bedrock client will be transferred to, or -1 if not set.
+     */
+    public int bedrockPort() {
+        return this.bedrockPort;
+    }
+
+    /**
+     * Sets the host for the Bedrock player to be transferred to
+     */
+    public void bedrockHost(@NonNull String host) {
+        if (host == null || host.isBlank()) {
+            throw new IllegalArgumentException("Server address cannot be null or blank");
+        }
+        this.bedrockHost = host;
+    }
+
+    /**
+     * Sets the port for the Bedrock player to be transferred to
+     */
+    public void bedrockPort(@IntRange(from = 0, to = 65535) int port) {
+        if (port < 0 || port > 65535) {
+            throw new IllegalArgumentException("Server port must be between 0 and 65535, was " + port);
+        }
+        this.bedrockPort = port;
+    }
+
     /**
      * Gets a map of the sessions current cookies.
+     *
      * @return the connections cookies
      */
     public @NonNull Map<String, byte[]> cookies() {

core/src/main/java/org/geysermc/geyser/translator/protocol/java/entity/player/JavaCookieRequestTranslator.java

@@ -27,9 +27,11 @@ package org.geysermc.geyser.translator.protocol.java.entity.player;
 
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.translator.protocol.PacketTranslator;
+import org.geysermc.geyser.translator.protocol.Translator;
 import org.geysermc.mcprotocollib.protocol.packet.common.clientbound.ClientboundCookieRequestPacket;
 import org.geysermc.mcprotocollib.protocol.packet.common.clientbound.ServerboundCookieResponsePacket;
 
+@Translator(packet = ClientboundCookieRequestPacket.class)
 public class JavaCookieRequestTranslator extends PacketTranslator<ClientboundCookieRequestPacket> {
     @Override
     public void translate(GeyserSession session, ClientboundCookieRequestPacket packet) {

core/src/main/java/org/geysermc/geyser/translator/protocol/java/entity/player/JavaStoreCookieTranslator.java

@@ -27,8 +27,10 @@ package org.geysermc.geyser.translator.protocol.java.entity.player;
 
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.translator.protocol.PacketTranslator;
+import org.geysermc.geyser.translator.protocol.Translator;
 import org.geysermc.mcprotocollib.protocol.packet.common.clientbound.ClientboundStoreCookiePacket;
 
+@Translator(packet = ClientboundStoreCookiePacket.class)
 public class JavaStoreCookieTranslator extends PacketTranslator<ClientboundStoreCookiePacket> {
     @Override
     public void translate(GeyserSession session, ClientboundStoreCookiePacket packet) {

core/src/main/java/org/geysermc/geyser/translator/protocol/java/entity/player/JavaTransferPacketTranslator.java

@@ -28,16 +28,27 @@ package org.geysermc.geyser.translator.protocol.java.entity.player;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.api.event.java.ServerTransferEvent;
 import org.geysermc.geyser.session.GeyserSession;
+import org.geysermc.geyser.text.MinecraftLocale;
 import org.geysermc.geyser.translator.protocol.PacketTranslator;
+import org.geysermc.geyser.translator.protocol.Translator;
 import org.geysermc.mcprotocollib.protocol.packet.common.clientbound.ClientboundTransferPacket;
 
+@Translator(packet = ClientboundTransferPacket.class)
 public class JavaTransferPacketTranslator extends PacketTranslator<ClientboundTransferPacket> {
     @Override
     public void translate(GeyserSession session, ClientboundTransferPacket packet) {
-        GeyserImpl.getInstance().eventBus().fire(new ServerTransferEvent(
+        ServerTransferEvent event = new ServerTransferEvent(
                 session,
                 packet.getHost(),
                 packet.getPort(),
-                session.getCookies()));
+                session.getCookies());
+
+        GeyserImpl.getInstance().eventBus().fire(event);
+
+        if (event.bedrockHost() != null && !event.bedrockHost().isBlank() && event.bedrockPort() != -1) {
+            session.transfer(event.bedrockHost(), event.bedrockPort());
+        } else {
+            session.disconnect(MinecraftLocale.getLocaleString("disconnect.transfer", session.locale()));
+        }
     }
 }