Start work on inventory/item translators

api/src/main/java/org/geysermc/api/Connector.java

@@ -29,6 +29,8 @@ import org.geysermc.api.command.CommandMap;
 import org.geysermc.api.logger.Logger;
 import org.geysermc.api.plugin.PluginManager;
 
+import java.util.concurrent.ScheduledExecutorService;
+
 public interface Connector {
 
     /**
@@ -52,6 +54,13 @@ public interface Connector {
      */
     PluginManager getPluginManager();
 
+    /**
+     * Returns the general thread pool
+     *
+     * @return the general thread pool
+     */
+    ScheduledExecutorService getGeneralThreadPool();
+
     /**
      * Shuts down the connector
      */

api/src/main/java/org/geysermc/api/Geyser.java

@@ -29,6 +29,8 @@ import org.geysermc.api.command.CommandMap;
 import org.geysermc.api.logger.Logger;
 import org.geysermc.api.plugin.PluginManager;
 
+import java.util.concurrent.ScheduledExecutorService;
+
 public class Geyser {
 
     private static Connector connector;
@@ -77,4 +79,8 @@ public class Geyser {
     public static CommandMap getCommandMap() {
         return connector.getCommandMap();
     }
+
+    public static ScheduledExecutorService getGeneralThreadPool() {
+        return connector.getGeneralThreadPool();
+    }
 }

connector/src/main/java/org/geysermc/connector/inventory/Inventory.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.inventory;
+
+import com.github.steveice10.mc.protocol.data.game.entity.metadata.ItemStack;
+import com.github.steveice10.mc.protocol.data.game.window.WindowType;
+import lombok.Getter;
+import lombok.Setter;
+
+public class Inventory {
+
+    @Getter
+    private int id;
+
+    @Getter
+    @Setter
+    private boolean open;
+
+    @Getter
+    private WindowType windowType;
+
+    @Getter
+    private int size;
+
+    @Getter
+    @Setter
+    private String title;
+
+    @Getter
+    @Setter
+    private ItemStack[] items;
+
+    public Inventory(int id, WindowType windowType, int size) {
+        this.id = id;
+        this.windowType = windowType;
+        this.size = size;
+
+        this.title = "Inventory";
+        this.items = new ItemStack[size];
+    }
+}

connector/src/main/java/org/geysermc/connector/network/session/GeyserSession.java

@@ -50,6 +50,7 @@ import org.geysermc.api.RemoteServer;
 import org.geysermc.api.session.AuthData;
 import org.geysermc.api.window.FormWindow;
 import org.geysermc.connector.GeyserConnector;
+import org.geysermc.connector.network.session.cache.InventoryCache;
 import org.geysermc.connector.network.session.cache.WindowCache;
 import org.geysermc.connector.network.translators.Registry;
 import org.geysermc.connector.utils.Toolbox;
@@ -70,6 +71,9 @@ public class GeyserSession implements PlayerSession, Player {
     @Getter
     private AuthData authenticationData;
 
+    @Getter
+    private InventoryCache inventoryCache;
+
     @Getter
     private WindowCache windowCache;
 
@@ -82,6 +86,7 @@ public class GeyserSession implements PlayerSession, Player {
         this.connector = connector;
         this.upstream = bedrockServerSession;
 
+        this.inventoryCache = new InventoryCache(this);
         this.windowCache = new WindowCache(this);
 
         this.loggedIn = false;

connector/src/main/java/org/geysermc/connector/network/session/cache/InventoryCache.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.session.cache;
+
+import com.github.steveice10.packetlib.packet.Packet;
+import lombok.Getter;
+import lombok.Setter;
+import org.geysermc.connector.inventory.Inventory;
+import org.geysermc.connector.network.session.GeyserSession;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class InventoryCache {
+
+    private GeyserSession session;
+
+    @Getter
+    @Setter
+    private Inventory openInventory;
+
+    @Getter
+    private Map<Integer, Inventory> inventories = new HashMap<Integer, Inventory>();
+
+    @Getter
+    private Map<Integer, List<Packet>> cachedPackets = new HashMap<Integer, List<Packet>>();
+
+    public InventoryCache(GeyserSession session) {
+        this.session = session;
+
+        // This is the player's inventory
+        inventories.put(0, new Inventory(0, null, 45));
+    }
+
+    public Inventory getPlayerInventory() {
+        return inventories.get(0);
+    }
+
+    public void cacheInventory(Inventory inventory) {
+        inventories.put(inventory.getId(), inventory);
+    }
+
+    public void uncacheInventory(int id) {
+        inventories.remove(id);
+    }
+
+    public void cachePacket(int id, Packet packet) {
+        List<Packet> packets = cachedPackets.getOrDefault(id, new ArrayList<Packet>());
+        packets.add(packet);
+        cachedPackets.put(id, packets);
+    }
+}

connector/src/main/java/org/geysermc/connector/network/session/cache/WindowCache.java

@@ -1,3 +1,28 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
 package org.geysermc.connector.network.session.cache;
 
 import com.nukkitx.protocol.bedrock.packet.ModalFormRequestPacket;
@@ -12,13 +37,13 @@ public class WindowCache {
 
     private GeyserSession session;
 
+    @Getter
+    private Map<Integer, FormWindow> windows = new HashMap<Integer, FormWindow>();
+
     public WindowCache(GeyserSession session) {
         this.session = session;
     }
 
-    @Getter
-    private Map<Integer, FormWindow> windows = new HashMap<Integer, FormWindow>();
-
     public void addWindow(FormWindow window) {
         windows.put(windows.size() + 1, window);
     }

connector/src/main/java/org/geysermc/connector/network/translators/Registry.java

@@ -50,9 +50,12 @@ public class Registry<T> {
 
     public <P extends T> void translate(Class<? extends P> clazz, P packet, GeyserSession session) {
         try {
-            ((PacketTranslator<P>) MAP.get(clazz)).translate(packet, session);
+            if (MAP.containsKey(clazz)) {
+                ((PacketTranslator<P>) MAP.get(clazz)).translate(packet, session);
+            }
         } catch (NullPointerException ex) {
             GeyserLogger.DEFAULT.debug("Could not translate packet " + packet.getClass().getSimpleName());
+            ex.printStackTrace();
         }
     }
 }

connector/src/main/java/org/geysermc/connector/network/translators/TranslatorsInit.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.connector.network.translators;
 
+import com.github.steveice10.mc.protocol.data.game.window.WindowType;
 import com.github.steveice10.mc.protocol.packet.ingame.server.ServerChatPacket;
 import com.github.steveice10.mc.protocol.packet.ingame.server.ServerJoinGamePacket;
 import com.github.steveice10.mc.protocol.packet.ingame.server.ServerTitlePacket;
@@ -32,6 +33,9 @@ import com.github.steveice10.mc.protocol.packet.ingame.server.entity.ServerEntit
 import com.github.steveice10.mc.protocol.packet.ingame.server.entity.ServerEntityPositionRotationPacket;
 import com.github.steveice10.mc.protocol.packet.ingame.server.entity.ServerEntityTeleportPacket;
 import com.github.steveice10.mc.protocol.packet.ingame.server.entity.ServerEntityVelocityPacket;
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerOpenWindowPacket;
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerSetSlotPacket;
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerWindowItemsPacket;
 import com.github.steveice10.mc.protocol.packet.ingame.server.world.ServerNotifyClientPacket;
 import com.github.steveice10.mc.protocol.packet.ingame.server.world.ServerUpdateTimePacket;
 import com.nukkitx.nbt.CompoundTagBuilder;
@@ -41,9 +45,13 @@ import com.nukkitx.nbt.tag.CompoundTag;
 import com.nukkitx.protocol.bedrock.packet.AnimatePacket;
 import com.nukkitx.protocol.bedrock.packet.CommandRequestPacket;
 import com.nukkitx.protocol.bedrock.packet.TextPacket;
+import lombok.Getter;
 import org.geysermc.connector.network.translators.bedrock.BedrockAnimateTranslator;
 import org.geysermc.connector.network.translators.bedrock.BedrockCommandRequestTranslator;
 import org.geysermc.connector.network.translators.bedrock.BedrockTextTranslator;
+import org.geysermc.connector.network.translators.inventory.GenericInventoryTranslator;
+import org.geysermc.connector.network.translators.inventory.InventoryTranslator;
+import org.geysermc.connector.network.translators.item.ItemTranslator;
 import org.geysermc.connector.network.translators.java.JavaChatTranslator;
 import org.geysermc.connector.network.translators.java.JavaEntityPositionRotationTranslator;
 import org.geysermc.connector.network.translators.java.JavaEntityPositionTranslator;
@@ -51,14 +59,25 @@ import org.geysermc.connector.network.translators.java.JavaEntityTeleportTransla
 import org.geysermc.connector.network.translators.java.JavaEntityVelocityTranslator;
 import org.geysermc.connector.network.translators.java.JavaJoinGameTranslator;
 import org.geysermc.connector.network.translators.java.JavaNotifyClientTranslator;
+import org.geysermc.connector.network.translators.java.JavaOpenWindowTranslator;
+import org.geysermc.connector.network.translators.java.JavaSetSlotTranslator;
 import org.geysermc.connector.network.translators.java.JavaTitleTranslator;
 import org.geysermc.connector.network.translators.java.JavaUpdateTimeTranslator;
+import org.geysermc.connector.network.translators.java.JavaWindowItemsTranslator;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
 
 public class TranslatorsInit {
 
+    @Getter
+    private static ItemTranslator itemTranslator;
+
+    @Getter
+    private static Map<WindowType, InventoryTranslator> inventoryTranslators = new HashMap<WindowType, InventoryTranslator>();
+
     private static final CompoundTag EMPTY_TAG = CompoundTagBuilder.builder().buildRootTag();
     public static final byte[] EMPTY_LEVEL_CHUNK_DATA;
 
@@ -86,9 +105,25 @@ public class TranslatorsInit {
         Registry.registerJava(ServerEntityTeleportPacket.class, new JavaEntityTeleportTranslator());
         Registry.registerJava(ServerEntityVelocityPacket.class, new JavaEntityVelocityTranslator());
         Registry.registerJava(ServerNotifyClientPacket.class, new JavaNotifyClientTranslator());
+        Registry.registerJava(ServerWindowItemsPacket.class, new JavaWindowItemsTranslator());
+        Registry.registerJava(ServerOpenWindowPacket.class, new JavaOpenWindowTranslator());
+        Registry.registerJava(ServerSetSlotPacket.class, new JavaSetSlotTranslator());
 
         Registry.registerBedrock(AnimatePacket.class, new BedrockAnimateTranslator());
         Registry.registerBedrock(CommandRequestPacket.class, new BedrockCommandRequestTranslator());
         Registry.registerBedrock(TextPacket.class, new BedrockTextTranslator());
+
+        itemTranslator = new ItemTranslator();
+
+        registerInventoryTranslators();
+    }
+
+    private static void registerInventoryTranslators() {
+        inventoryTranslators.put(WindowType.GENERIC_9X1, new GenericInventoryTranslator());
+        inventoryTranslators.put(WindowType.GENERIC_9X2, new GenericInventoryTranslator());
+        inventoryTranslators.put(WindowType.GENERIC_9X3, new GenericInventoryTranslator());
+        inventoryTranslators.put(WindowType.GENERIC_9X4, new GenericInventoryTranslator());
+        inventoryTranslators.put(WindowType.GENERIC_9X5, new GenericInventoryTranslator());
+        inventoryTranslators.put(WindowType.GENERIC_9X6, new GenericInventoryTranslator());
     }
 }

connector/src/main/java/org/geysermc/connector/network/translators/inventory/GenericInventoryTranslator.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.inventory;
+
+import com.flowpowered.math.vector.Vector3i;
+import com.nukkitx.protocol.bedrock.data.ContainerId;
+import com.nukkitx.protocol.bedrock.data.ItemData;
+import com.nukkitx.protocol.bedrock.packet.ContainerOpenPacket;
+import com.nukkitx.protocol.bedrock.packet.InventoryContentPacket;
+import com.nukkitx.protocol.bedrock.packet.InventorySlotPacket;
+import org.geysermc.connector.inventory.Inventory;
+import org.geysermc.connector.network.session.GeyserSession;
+import org.geysermc.connector.network.translators.TranslatorsInit;
+import org.geysermc.connector.utils.InventoryUtils;
+
+public class GenericInventoryTranslator extends InventoryTranslator {
+
+    @Override
+    public void prepareInventory(GeyserSession session, Inventory inventory) {
+        // TODO: Add code here
+    }
+
+    @Override
+    public void openInventory(GeyserSession session, Inventory inventory) {
+        ContainerOpenPacket containerOpenPacket = new ContainerOpenPacket();
+        containerOpenPacket.setWindowId((byte) inventory.getId());
+        containerOpenPacket.setType((byte) 0);
+        containerOpenPacket.setBlockPosition(new Vector3i(0, 0, 0));
+        session.getUpstream().sendPacket(containerOpenPacket);
+    }
+
+    @Override
+    public void updateInventory(GeyserSession session, Inventory inventory) {
+        ContainerId containerId = InventoryUtils.getContainerId(inventory.getId());
+        if (containerId == null)
+            return;
+
+        ItemData[] bedrockItems = new ItemData[inventory.getItems().length];
+        for (int i = 0; i < bedrockItems.length; i++) {
+            bedrockItems[i] = TranslatorsInit.getItemTranslator().translateToBedrock(inventory.getItems()[i]);
+        }
+
+        InventoryContentPacket contentPacket = new InventoryContentPacket();
+        contentPacket.setContainerId(containerId);
+        contentPacket.setContents(bedrockItems);
+        session.getUpstream().sendPacket(contentPacket);
+    }
+
+    @Override
+    public void updateSlot(GeyserSession session, Inventory inventory, int slot) {
+        ContainerId containerId = InventoryUtils.getContainerId(inventory.getId());
+        if (containerId == null)
+            return;
+
+        InventorySlotPacket slotPacket = new InventorySlotPacket();
+        slotPacket.setContainerId(containerId);
+        slotPacket.setSlot(TranslatorsInit.getItemTranslator().translateToBedrock(inventory.getItems()[slot]));
+        slotPacket.setInventorySlot(slot);
+        session.getUpstream().sendPacket(slotPacket);
+    }
+}

connector/src/main/java/org/geysermc/connector/network/translators/inventory/InventoryTranslator.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.inventory;
+
+import org.geysermc.connector.inventory.Inventory;
+import org.geysermc.connector.network.session.GeyserSession;
+
+public abstract class InventoryTranslator {
+
+    public abstract void prepareInventory(GeyserSession session, Inventory inventory);
+    public abstract void openInventory(GeyserSession session, Inventory inventory);
+    public abstract void updateInventory(GeyserSession session, Inventory inventory);
+    public abstract void updateSlot(GeyserSession session, Inventory inventory, int slot);
+
+}

connector/src/main/java/org/geysermc/connector/network/translators/item/BedrockItem.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.item;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@Getter
+@AllArgsConstructor
+public class BedrockItem {
+
+    private String identifier;
+    private int id;
+    private int data;
+}

connector/src/main/java/org/geysermc/connector/network/translators/item/ItemTranslator.java

@@ -0,0 +1,324 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.item;
+
+import com.github.steveice10.mc.protocol.data.game.entity.metadata.ItemStack;
+import com.github.steveice10.opennbt.tag.builtin.ByteArrayTag;
+import com.github.steveice10.opennbt.tag.builtin.ByteTag;
+import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
+import com.github.steveice10.opennbt.tag.builtin.DoubleTag;
+import com.github.steveice10.opennbt.tag.builtin.FloatTag;
+import com.github.steveice10.opennbt.tag.builtin.IntArrayTag;
+import com.github.steveice10.opennbt.tag.builtin.IntTag;
+import com.github.steveice10.opennbt.tag.builtin.ListTag;
+import com.github.steveice10.opennbt.tag.builtin.LongArrayTag;
+import com.github.steveice10.opennbt.tag.builtin.LongTag;
+import com.github.steveice10.opennbt.tag.builtin.ShortTag;
+import com.github.steveice10.opennbt.tag.builtin.StringTag;
+import com.github.steveice10.opennbt.tag.builtin.Tag;
+import com.nukkitx.protocol.bedrock.data.ItemData;
+import com.nukkitx.protocol.bedrock.packet.StartGamePacket;
+import org.geysermc.connector.utils.Toolbox;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class ItemTranslator {
+
+    private static Map<String, String> identifiers = new HashMap<String, String>();
+
+    static {
+        // Key: java translation
+        // Value: bedrock translation
+        identifiers.put("grass_block", "grass");
+        identifiers.put("granite", "stone:1");
+        identifiers.put("polished_granite", "stone:2");
+        identifiers.put("diorite", "stone:3");
+        identifiers.put("polished_diorite", "stone:4");
+        identifiers.put("andesite", "stone:5");
+        identifiers.put("polished_andesite", "stone:6");
+        identifiers.put("spurce_log", "log:1");
+        identifiers.put("birch_log", "log:2");
+        identifiers.put("jungle_log", "log:3");
+        identifiers.put("acacia_log", "log:4");
+        identifiers.put("dark_oak_log", "log:5");
+    }
+
+    public ItemStack translateToJava(ItemData data) {
+        JavaItem javaItem = getJavaItem(data);
+
+        if (data.getTag() == null) {
+            return new ItemStack(javaItem.getId(), data.getCount());
+        }
+        return new ItemStack(javaItem.getId(), data.getCount(), translateToJavaNBT(data.getTag()));
+    }
+
+    public ItemData translateToBedrock(ItemStack stack) {
+        // Most likely air if null
+        if (stack == null) {
+            return ItemData.AIR;
+        }
+
+        BedrockItem bedrockItem = getBedrockItem(stack);
+        if (stack.getNBT() == null) {
+            return ItemData.of(bedrockItem.getId(), (short) bedrockItem.getData(), stack.getAmount());
+        }
+        return ItemData.of(bedrockItem.getId(), (short) bedrockItem.getData(), stack.getAmount(), translateToBedrockNBT(stack.getNBT()));
+    }
+
+    public BedrockItem getBedrockItem(ItemStack stack) {
+       for (Map.Entry<String, JavaItem> javaItems : Toolbox.JAVA_ITEMS.entrySet()) {
+           if (javaItems.getValue().getId() != stack.getId())
+               continue;
+
+           JavaItem javaItem = javaItems.getValue();
+           String identifier = getBedrockIdentifier(javaItem.getIdentifier().replace("minecraft:", ""));
+           if (!Toolbox.BEDROCK_ITEMS.containsKey(identifier))
+                continue;
+
+           return Toolbox.BEDROCK_ITEMS.get(identifier);
+       }
+
+       return new BedrockItem("minecraft:air", 0, 0);
+    }
+
+    public JavaItem getJavaItem(ItemData data) {
+        for (Map.Entry<String, BedrockItem> bedrockItems : Toolbox.BEDROCK_ITEMS.entrySet()) {
+            if (bedrockItems.getValue().getId() != data.getId())
+                continue;
+
+            String identifier = getJavaIdentifier(bedrockItems.getKey().replace("minecraft:", ""));
+            if (!Toolbox.JAVA_ITEMS.containsKey(identifier))
+                continue;
+
+            return Toolbox.JAVA_ITEMS.get(identifier);
+        }
+
+        return new JavaItem("minecraft:air", 0);
+    }
+
+    public String getBedrockIdentifier(String javaIdentifier) {
+        if (!identifiers.containsKey(javaIdentifier))
+            return "minecraft:" + javaIdentifier;
+
+        return "minecraft:" + identifiers.get(javaIdentifier);
+    }
+
+    public String getJavaIdentifier(String bedrockIdentifier) {
+        for (Map.Entry<String, String> entry : identifiers.entrySet()) {
+            if (entry.getValue().equals(bedrockIdentifier)) {
+                return "minecraft:" + entry.getKey();
+            }
+        }
+
+        return "minecraft:" + bedrockIdentifier;
+    }
+
+    private CompoundTag translateToJavaNBT(com.nukkitx.nbt.tag.CompoundTag tag) {
+        CompoundTag javaTag = new CompoundTag(tag.getName());
+        Map<String, Tag> javaValue = javaTag.getValue();
+        if (tag.getValue() != null && !tag.getValue().isEmpty()) {
+            for (String str : tag.getValue().keySet()) {
+                com.nukkitx.nbt.tag.Tag bedrockTag = tag.get(str);
+                Tag translatedTag = translateToJavaNBT(bedrockTag);
+                if (translatedTag == null)
+                    continue;
+
+                javaValue.put(str, translatedTag);
+            }
+        }
+
+        return javaTag;
+    }
+
+    private Tag translateToJavaNBT(com.nukkitx.nbt.tag.Tag tag) {
+        if (tag instanceof com.nukkitx.nbt.tag.ByteArrayTag) {
+            com.nukkitx.nbt.tag.ByteArrayTag byteArrayTag = (com.nukkitx.nbt.tag.ByteArrayTag) tag;
+            return new ByteArrayTag(byteArrayTag.getName(), byteArrayTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.ByteTag) {
+            com.nukkitx.nbt.tag.ByteTag byteTag = (com.nukkitx.nbt.tag.ByteTag) tag;
+            return new ByteTag(byteTag.getName(), byteTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.DoubleTag) {
+            com.nukkitx.nbt.tag.DoubleTag doubleTag = (com.nukkitx.nbt.tag.DoubleTag) tag;
+            return new DoubleTag(doubleTag.getName(), doubleTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.FloatTag) {
+            com.nukkitx.nbt.tag.FloatTag floatTag = (com.nukkitx.nbt.tag.FloatTag) tag;
+            return new FloatTag(floatTag.getName(), floatTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.IntArrayTag) {
+            com.nukkitx.nbt.tag.IntArrayTag intArrayTag = (com.nukkitx.nbt.tag.IntArrayTag) tag;
+            return new IntArrayTag(intArrayTag.getName(), intArrayTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.IntTag) {
+            com.nukkitx.nbt.tag.IntTag intTag = (com.nukkitx.nbt.tag.IntTag) tag;
+            return new IntTag(intTag.getName(), intTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.LongArrayTag) {
+            com.nukkitx.nbt.tag.LongArrayTag longArrayTag = (com.nukkitx.nbt.tag.LongArrayTag) tag;
+            return new LongArrayTag(longArrayTag.getName(), longArrayTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.LongTag) {
+            com.nukkitx.nbt.tag.LongTag longTag = (com.nukkitx.nbt.tag.LongTag) tag;
+            return new LongTag(longTag.getName(), longTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.ShortTag) {
+            com.nukkitx.nbt.tag.ShortTag shortTag = (com.nukkitx.nbt.tag.ShortTag) tag;
+            return new ShortTag(shortTag.getName(), shortTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.StringTag) {
+            com.nukkitx.nbt.tag.StringTag stringTag = (com.nukkitx.nbt.tag.StringTag) tag;
+            return new StringTag(stringTag.getName(), stringTag.getValue());
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.ListTag) {
+            com.nukkitx.nbt.tag.ListTag listTag = (com.nukkitx.nbt.tag.ListTag) tag;
+
+            List<Tag> tags = new ArrayList<Tag>();
+            for (Object value : listTag.getValue()) {
+                if (!(value instanceof com.nukkitx.nbt.tag.Tag))
+                    continue;
+
+                com.nukkitx.nbt.tag.Tag tagValue = (com.nukkitx.nbt.tag.Tag) value;
+                Tag javaTag = translateToJavaNBT(tagValue);
+                if (javaTag != null)
+                    tags.add(javaTag);
+            }
+            return new ListTag(listTag.getName(), tags);
+        }
+
+        if (tag instanceof com.nukkitx.nbt.tag.CompoundTag) {
+            return translateToJavaNBT((com.nukkitx.nbt.tag.CompoundTag) tag);
+        }
+
+        return null;
+    }
+
+    private com.nukkitx.nbt.tag.CompoundTag translateToBedrockNBT(CompoundTag tag) {
+        Map<String, com.nukkitx.nbt.tag.Tag<?>> javaValue = new HashMap<String, com.nukkitx.nbt.tag.Tag<?>>();
+        if (tag.getValue() != null && !tag.getValue().isEmpty()) {
+            for (String str : tag.getValue().keySet()) {
+                Tag javaTag = tag.get(str);
+                com.nukkitx.nbt.tag.Tag translatedTag = translateToBedrockNBT(javaTag);
+                if (translatedTag == null)
+                    continue;
+
+                javaValue.put(str, translatedTag);
+            }
+        }
+
+        com.nukkitx.nbt.tag.CompoundTag bedrockTag = new com.nukkitx.nbt.tag.CompoundTag(tag.getName(), javaValue);
+        return bedrockTag;
+    }
+
+    private com.nukkitx.nbt.tag.Tag translateToBedrockNBT(Tag tag) {
+        if (tag instanceof ByteArrayTag) {
+            ByteArrayTag byteArrayTag = (ByteArrayTag) tag;
+            return new com.nukkitx.nbt.tag.ByteArrayTag(byteArrayTag.getName(), byteArrayTag.getValue());
+        }
+
+        if (tag instanceof ByteTag) {
+            ByteTag byteTag = (ByteTag) tag;
+            return new com.nukkitx.nbt.tag.ByteTag(byteTag.getName(), byteTag.getValue());
+        }
+
+        if (tag instanceof DoubleTag) {
+            DoubleTag doubleTag = (DoubleTag) tag;
+            return new com.nukkitx.nbt.tag.DoubleTag(doubleTag.getName(), doubleTag.getValue());
+        }
+
+        if (tag instanceof FloatTag) {
+            FloatTag floatTag = (FloatTag) tag;
+            return new com.nukkitx.nbt.tag.FloatTag(floatTag.getName(), floatTag.getValue());
+        }
+
+        if (tag instanceof IntArrayTag) {
+            IntArrayTag intArrayTag = (IntArrayTag) tag;
+            return new com.nukkitx.nbt.tag.IntArrayTag(intArrayTag.getName(), intArrayTag.getValue());
+        }
+
+        if (tag instanceof IntTag) {
+            IntTag intTag = (IntTag) tag;
+            return new com.nukkitx.nbt.tag.IntTag(intTag.getName(), intTag.getValue());
+        }
+
+        if (tag instanceof LongArrayTag) {
+            LongArrayTag longArrayTag = (LongArrayTag) tag;
+            return new com.nukkitx.nbt.tag.LongArrayTag(longArrayTag.getName(), longArrayTag.getValue());
+        }
+
+        if (tag instanceof LongTag) {
+            LongTag longTag = (LongTag) tag;
+            return new com.nukkitx.nbt.tag.LongTag(longTag.getName(), longTag.getValue());
+        }
+
+        if (tag instanceof ShortTag) {
+            ShortTag shortTag = (ShortTag) tag;
+            return new com.nukkitx.nbt.tag.ShortTag(shortTag.getName(), shortTag.getValue());
+        }
+
+        if (tag instanceof StringTag) {
+            StringTag stringTag = (StringTag) tag;
+            return new com.nukkitx.nbt.tag.StringTag(stringTag.getName(), stringTag.getValue());
+        }
+
+        if (tag instanceof ListTag) {
+            ListTag listTag = (ListTag) tag;
+
+            List<com.nukkitx.nbt.tag.Tag> tags = new ArrayList<com.nukkitx.nbt.tag.Tag>();
+            for (Object value : listTag.getValue()) {
+                if (!(value instanceof Tag))
+                    continue;
+
+                Tag tagValue = (Tag) value;
+                com.nukkitx.nbt.tag.Tag bedrockTag = translateToBedrockNBT(tagValue);
+                if (bedrockTag != null)
+                    tags.add(bedrockTag);
+            }
+            // TODO: Fix unchecked call here
+            return new com.nukkitx.nbt.tag.ListTag(listTag.getName(), listTag.getElementType(), tags);
+        }
+
+        if (tag instanceof CompoundTag) {
+            return translateToBedrockNBT((CompoundTag) tag);
+        }
+
+        return null;
+    }
+}

connector/src/main/java/org/geysermc/connector/network/translators/item/JavaItem.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.item;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@Getter
+@AllArgsConstructor
+public class JavaItem {
+
+    private String identifier;
+    private int id;
+}

connector/src/main/java/org/geysermc/connector/network/translators/java/JavaOpenWindowTranslator.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.java;
+
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerOpenWindowPacket;
+import org.geysermc.connector.network.session.GeyserSession;
+import org.geysermc.connector.network.translators.PacketTranslator;
+import org.geysermc.connector.utils.InventoryUtils;
+
+public class JavaOpenWindowTranslator extends PacketTranslator<ServerOpenWindowPacket> {
+
+    @Override
+    public void translate(ServerOpenWindowPacket packet, GeyserSession session) {
+        InventoryUtils.openInventory(session, packet);
+    }
+}

connector/src/main/java/org/geysermc/connector/network/translators/java/JavaSetSlotTranslator.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.java;
+
+import com.github.steveice10.mc.protocol.data.game.entity.metadata.ItemStack;
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerSetSlotPacket;
+import org.geysermc.connector.inventory.Inventory;
+import org.geysermc.connector.network.session.GeyserSession;
+import org.geysermc.connector.network.session.cache.InventoryCache;
+import org.geysermc.connector.network.translators.PacketTranslator;
+import org.geysermc.connector.utils.InventoryUtils;
+
+public class JavaSetSlotTranslator extends PacketTranslator<ServerSetSlotPacket> {
+
+    @Override
+    public void translate(ServerSetSlotPacket packet, GeyserSession session) {
+        InventoryCache inventoryCache = session.getInventoryCache();
+        if (!inventoryCache.getInventories().containsKey(packet.getWindowId())) {
+            inventoryCache.cachePacket(packet.getWindowId(), packet);
+            return;
+        }
+
+        Inventory inventory = inventoryCache.getInventories().get(packet.getWindowId());
+        if (packet.getWindowId() != 0 && inventory.getWindowType() == null)
+            return;
+
+        // Player inventory
+        if (packet.getWindowId() == 0) {
+            if (packet.getSlot() >= inventory.getItems().length)
+                return; // Most likely not a player inventory
+
+            ItemStack[] items = inventory.getItems();
+            items[packet.getSlot()] = packet.getItem();
+            inventory.setItems(items);
+
+            InventoryUtils.refreshPlayerInventory(session, inventory);
+
+            if (inventory.isOpen()) {
+                InventoryUtils.updateSlot(session, packet);
+            } else {
+                inventoryCache.cachePacket(packet.getWindowId(), packet);
+            }
+        }
+    }
+}

connector/src/main/java/org/geysermc/connector/network/translators/java/JavaWindowItemsTranslator.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2019 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.connector.network.translators.java;
+
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerWindowItemsPacket;
+import org.geysermc.connector.inventory.Inventory;
+import org.geysermc.connector.network.session.GeyserSession;
+import org.geysermc.connector.network.session.cache.InventoryCache;
+import org.geysermc.connector.network.translators.PacketTranslator;
+import org.geysermc.connector.utils.InventoryUtils;
+
+public class JavaWindowItemsTranslator extends PacketTranslator<ServerWindowItemsPacket> {
+
+    @Override
+    public void translate(ServerWindowItemsPacket packet, GeyserSession session) {
+        InventoryCache inventoryCache = session.getInventoryCache();
+        if (!inventoryCache.getInventories().containsKey(packet.getWindowId())) {
+            inventoryCache.cachePacket(packet.getWindowId(), packet);
+            return;
+        }
+
+        Inventory inventory = inventoryCache.getInventories().get(packet.getWindowId());
+        // Player inventory
+        if (packet.getWindowId() == 0) {
+            inventory.setItems(packet.getItems());
+            InventoryUtils.refreshPlayerInventory(session, inventory);
+            return;
+        }
+
+        InventoryUtils.updateInventory(session, packet);
+    }
+}

connector/src/main/java/org/geysermc/connector/utils/InventoryUtils.java

@@ -0,0 +1,122 @@
+package org.geysermc.connector.utils;
+
+import com.github.steveice10.mc.protocol.data.game.entity.metadata.ItemStack;
+import com.github.steveice10.mc.protocol.packet.ingame.client.window.ClientCloseWindowPacket;
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerOpenWindowPacket;
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerSetSlotPacket;
+import com.github.steveice10.mc.protocol.packet.ingame.server.window.ServerWindowItemsPacket;
+import com.github.steveice10.packetlib.packet.Packet;
+import com.nukkitx.protocol.bedrock.data.ContainerId;
+import com.nukkitx.protocol.bedrock.data.ItemData;
+import com.nukkitx.protocol.bedrock.packet.InventoryContentPacket;
+import org.geysermc.api.Geyser;
+import org.geysermc.connector.inventory.Inventory;
+import org.geysermc.connector.network.session.GeyserSession;
+import org.geysermc.connector.network.translators.TranslatorsInit;
+import org.geysermc.connector.network.translators.inventory.InventoryTranslator;
+
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+public class InventoryUtils {
+
+    public static void refreshPlayerInventory(GeyserSession session, Inventory inventory) {
+        InventoryContentPacket inventoryContentPacket = new InventoryContentPacket();
+        inventoryContentPacket.setContainerId(ContainerId.INVENTORY);
+
+        ItemData[] contents = new ItemData[40];
+        // Inventory
+        for (int i = 9; i < 36; i++) {
+            contents[i] = TranslatorsInit.getItemTranslator().translateToBedrock(inventory.getItems()[i]);
+        }
+
+        // Hotbar
+        for (int i = 36; i < 45; i++) {
+            contents[i - 36] = TranslatorsInit.getItemTranslator().translateToBedrock(inventory.getItems()[i]);
+        }
+
+        // Armor
+        for (int i = 5; i < 9; i++) {
+            contents[i + 31] = TranslatorsInit.getItemTranslator().translateToBedrock(inventory.getItems()[i]);
+        }
+
+        inventoryContentPacket.setContents(contents);
+        session.getUpstream().sendPacket(inventoryContentPacket);
+    }
+
+    public static void openInventory(GeyserSession session, ServerOpenWindowPacket packet) {
+        Inventory inventory = new Inventory(packet.getWindowId(), packet.getType(), 45); // TODO: Find a way to set this value
+        session.getInventoryCache().getInventories().put(packet.getWindowId(), inventory);
+        session.getInventoryCache().setOpenInventory(inventory);
+
+        InventoryTranslator translator = TranslatorsInit.getInventoryTranslators().get(inventory.getWindowType());
+        translator.prepareInventory(session, inventory);
+        Geyser.getGeneralThreadPool().schedule(() -> {
+            List<Packet> packets = session.getInventoryCache().getCachedPackets().get(inventory.getId());
+            packets.forEach(itemPacket -> {
+                if (itemPacket != null) {
+                    if (ServerWindowItemsPacket.class.isAssignableFrom(itemPacket.getClass())) {
+                        updateInventory(session, (ServerWindowItemsPacket) itemPacket);
+                    }
+                }
+            });
+        }, 200, TimeUnit.MILLISECONDS);
+    }
+
+    public static void updateInventory(GeyserSession session, ServerWindowItemsPacket packet) {
+        if (packet.getWindowId() == 0)
+            return;
+
+        if (session.getInventoryCache().getOpenInventory() == null || !session.getInventoryCache().getInventories().containsKey(packet.getWindowId()))
+            return;
+
+        Inventory openInventory = session.getInventoryCache().getOpenInventory();
+        if (packet.getWindowId() != openInventory.getId())
+            return;
+
+        InventoryTranslator translator = TranslatorsInit.getInventoryTranslators().get(openInventory.getWindowType());
+        if (translator == null) {
+            session.getDownstream().getSession().send(new ClientCloseWindowPacket(packet.getWindowId()));
+            return;
+        }
+
+        openInventory.setItems(packet.getItems());
+        translator.updateInventory(session, openInventory);
+    }
+
+    public static void updateSlot(GeyserSession session, ServerSetSlotPacket packet) {
+        if (packet.getWindowId() == 0)
+            return;
+
+        if (session.getInventoryCache().getOpenInventory() == null || !session.getInventoryCache().getInventories().containsKey(packet.getWindowId()))
+            return;
+
+        Inventory openInventory = session.getInventoryCache().getOpenInventory();
+        if (packet.getWindowId() != openInventory.getId())
+            return;
+
+        InventoryTranslator translator = TranslatorsInit.getInventoryTranslators().get(openInventory.getWindowType());
+        if (translator == null) {
+            session.getDownstream().getSession().send(new ClientCloseWindowPacket(packet.getWindowId()));
+            return;
+        }
+
+        if (packet.getSlot() >= openInventory.getSize()) {
+            session.getDownstream().getSession().send(new ClientCloseWindowPacket(packet.getWindowId()));
+            return;
+        }
+
+        ItemStack[] items = openInventory.getItems();
+        items[packet.getSlot()] = packet.getItem();
+        translator.updateSlot(session, openInventory, packet.getSlot());
+    }
+
+    public static ContainerId getContainerId(int id) {
+        for (ContainerId value : ContainerId.values()) {
+            if (value.id() == id)
+                return value;
+        }
+
+        return null;
+    }
+}

connector/src/main/java/org/geysermc/connector/utils/Toolbox.java

@@ -1,11 +1,14 @@
 package org.geysermc.connector.utils;
 
+import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.nukkitx.network.VarInts;
 import com.nukkitx.protocol.bedrock.packet.StartGamePacket;
 import com.nukkitx.protocol.bedrock.v361.BedrockUtils;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
+import org.geysermc.connector.network.translators.item.BedrockItem;
+import org.geysermc.connector.network.translators.item.JavaItem;
 
 import java.io.InputStream;
 import java.util.*;
@@ -23,6 +26,16 @@ public class Toolbox {
             e.printStackTrace();
         }
 
+        Map<String, BedrockItem> bedrockItems = new HashMap<String, BedrockItem>();
+        for (Map<String, Object> e : entries) {
+            BedrockItem bedrockItem = new BedrockItem((String) e.get("name"), (int) e.get("id"), (int) e.get("data"));
+            if (bedrockItem.getData() != 0) {
+                bedrockItems.put(bedrockItem.getIdentifier() + ":" + bedrockItem.getData(), bedrockItem);
+            } else {
+                bedrockItems.put(bedrockItem.getIdentifier(), bedrockItem);
+            }
+        }
+
         ByteBuf b = Unpooled.buffer();
         VarInts.writeUnsignedInt(b, entries.size());
         for (Map<String, Object> e : entries) {
@@ -46,17 +59,43 @@ public class Toolbox {
             e.printStackTrace();
         }
 
-        ArrayList<StartGamePacket.ItemEntry> l = new ArrayList<>();
+        List<StartGamePacket.ItemEntry> l = new ArrayList<>();
         for (HashMap e : s) {
             l.add(new StartGamePacket.ItemEntry((String) e.get("name"), (short) ((int) e.get("id"))));
+            if (!bedrockItems.containsKey(e.get("name"))) {
+                BedrockItem bedrockItem = new BedrockItem((String) e.get("name"), ((int) e.get("id")), 0);
+                bedrockItems.put(bedrockItem.getIdentifier(), bedrockItem);
+            }
         }
 
         ITEMS = l;
+
+        BEDROCK_ITEMS = bedrockItems;
+
+        InputStream javaItemStream = Toolbox.class.getClassLoader().getResourceAsStream("java_items.json");
+        ObjectMapper javaItemMapper = new ObjectMapper();
+        Map<String, HashMap> javaItemList = new HashMap<String, HashMap>();
+        try {
+            javaItemList = javaItemMapper.readValue(javaItemStream, new TypeReference<Map<String, HashMap>>(){});
+        } catch (Exception ex) {
+            ex.printStackTrace();
+        }
+
+        Map<String, JavaItem> javaItems = new HashMap<String, JavaItem>();
+
+        for (String str : javaItemList.keySet()) {
+            javaItems.put(str, new JavaItem(str, (int) javaItemList.get(str).get("protocol_id")));
+        }
+
+        JAVA_ITEMS = javaItems;
     }
 
     public static final Collection<StartGamePacket.ItemEntry> ITEMS;
 
     public static final ByteBuf CACHED_PALLETE;
 
+    public static final Map<String, BedrockItem> BEDROCK_ITEMS;
+    public static final Map<String, JavaItem> JAVA_ITEMS;
+
     //public static final byte[] EMPTY_CHUNK;
 }