SBDevelopment/MapReflectionAPI
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♻️ Merged reflection utility classes

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This commit is contained in:
SBDeveloper 2022-07-01 13:27:07 +02:00
parent e110f0afcc
commit 13573d4add
5 changed files with 300 additions and 417 deletions
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4
src/main/java/tech/sbdevelopment/mapreflectionapi/MapReflectionAPI.java
View file

@ -30,7 +30,7 @@ import org.bukkit.plugin.java.JavaPlugin;
import tech.sbdevelopment.mapreflectionapi.api.MapManager;
import tech.sbdevelopment.mapreflectionapi.listeners.MapListener;
import tech.sbdevelopment.mapreflectionapi.listeners.PacketListener;
import tech.sbdevelopment.mapreflectionapi.utils.ReflectionUtils;
import tech.sbdevelopment.mapreflectionapi.utils.ReflectionUtil;
import java.util.logging.Level;
@ -66,7 +66,7 @@ public class MapReflectionAPI extends JavaPlugin {
getLogger().info("MapReflectionAPI v" + getDescription().getVersion() + "");
getLogger().info("Made by © Copyright SBDevelopment 2022");
if (!ReflectionUtils.supports(12)) {
if (!ReflectionUtil.supports(12)) {
getLogger().severe("MapReflectionAPI only supports Minecraft 1.12 - 1.19!");
Bukkit.getPluginManager().disablePlugin(this);
return;

11
src/main/java/tech/sbdevelopment/mapreflectionapi/api/MapSender.java
View file

@ -27,7 +27,6 @@ import org.bukkit.Bukkit;
import org.bukkit.entity.Player;
import tech.sbdevelopment.mapreflectionapi.MapReflectionAPI;
import tech.sbdevelopment.mapreflectionapi.utils.ReflectionUtil;
import tech.sbdevelopment.mapreflectionapi.utils.ReflectionUtils;
import java.util.ArrayList;
import java.util.List;
@ -73,8 +72,8 @@ public class MapSender {
}, 0, 2);
}
private static final Class<?> packetPlayOutMapClass = ReflectionUtils.getNMSClass("network.protocol.game", "PacketPlayOutMap");
private static final Class<?> worldMapData = ReflectionUtils.supports(17) ? ReflectionUtils.getNMSClass("world.level.saveddata.maps", "WorldMap") : null;
private static final Class<?> packetPlayOutMapClass = ReflectionUtil.getNMSClass("network.protocol.game", "PacketPlayOutMap");
private static final Class<?> worldMapData = ReflectionUtil.supports(17) ? ReflectionUtil.getNMSClass("world.level.saveddata.maps", "WorldMap") : null;
/**
* Send a map to a player
@ -101,7 +100,7 @@ public class MapSender {
final int id = -id0;
Object packet;
if (ReflectionUtils.supports(17)) { //1.17+
if (ReflectionUtil.supports(17)) { //1.17+
Object updateData = ReflectionUtil.callConstructor(worldMapData,
content.minX, //X pos
content.minY, //Y pos
@ -117,7 +116,7 @@ public class MapSender {
new ArrayList<>(), //Icons
updateData
);
} else if (ReflectionUtils.supports(14)) { //1.16-1.14
} else if (ReflectionUtil.supports(14)) { //1.16-1.14
packet = ReflectionUtil.callConstructor(packetPlayOutMapClass,
id, //ID
(byte) 0, //Scale
@ -144,7 +143,7 @@ public class MapSender {
);
}
ReflectionUtils.sendPacket(player, packet);
ReflectionUtil.sendPacket(player, packet);
}
static final class QueuedMap {
private final int id;

53
src/main/java/tech/sbdevelopment/mapreflectionapi/api/MapWrapper.java
View file

@ -32,7 +32,6 @@ import org.bukkit.metadata.FixedMetadataValue;
import tech.sbdevelopment.mapreflectionapi.MapReflectionAPI;
import tech.sbdevelopment.mapreflectionapi.api.exceptions.MapLimitExceededException;
import tech.sbdevelopment.mapreflectionapi.utils.ReflectionUtil;
import tech.sbdevelopment.mapreflectionapi.utils.ReflectionUtils;
import java.util.*;
@ -48,14 +47,14 @@ public class MapWrapper {
this.content = image;
}
private static final Class<?> craftStackClass = ReflectionUtils.getCraftClass("CraftItemStack");
private static final Class<?> setSlotPacketClass = ReflectionUtils.getNMSClass("network.protocol.game", "PacketPlayOutSetSlot");
private static final Class<?> tagCompoundClass = ReflectionUtils.getCraftClass("NBTTagCompound");
private static final Class<?> entityClass = ReflectionUtils.getNMSClass("world.entity", "Entity");
private static final Class<?> dataWatcherClass = ReflectionUtils.getNMSClass("network.syncher", "DataWatcher");
private static final Class<?> entityMetadataPacketClass = ReflectionUtils.getNMSClass("network.protocol.game", "PacketPlayOutEntityMetadata");
private static final Class<?> entityItemFrameClass = ReflectionUtils.getNMSClass("world.entity.decoration", "EntityItemFrame");
private static final Class<?> dataWatcherItemClass = ReflectionUtils.getNMSClass("network.syncher", "DataWatcher$Item");
private static final Class<?> craftStackClass = ReflectionUtil.getCraftClass("CraftItemStack");
private static final Class<?> setSlotPacketClass = ReflectionUtil.getNMSClass("network.protocol.game", "PacketPlayOutSetSlot");
private static final Class<?> tagCompoundClass = ReflectionUtil.getCraftClass("NBTTagCompound");
private static final Class<?> entityClass = ReflectionUtil.getNMSClass("world.entity", "Entity");
private static final Class<?> dataWatcherClass = ReflectionUtil.getNMSClass("network.syncher", "DataWatcher");
private static final Class<?> entityMetadataPacketClass = ReflectionUtil.getNMSClass("network.protocol.game", "PacketPlayOutEntityMetadata");
private static final Class<?> entityItemFrameClass = ReflectionUtil.getNMSClass("world.entity.decoration", "EntityItemFrame");
private static final Class<?> dataWatcherItemClass = ReflectionUtil.getNMSClass("network.syncher", "DataWatcher$Item");
protected MapController controller = new MapController() {
private final Map<UUID, Integer> viewers = new HashMap<>();
@ -142,17 +141,17 @@ public class MapWrapper {
slot = 8 - (slot - 36);
}
Object playerHandle = ReflectionUtils.getHandle(player);
Object inventoryMenu = ReflectionUtil.getField(playerHandle, ReflectionUtils.supports(19) ? "bT" : ReflectionUtils.supports(17) ? "bU" : "defaultContainer");
int windowId = (int) ReflectionUtil.getField(inventoryMenu, ReflectionUtils.supports(17) ? "j" : "windowId");
Object playerHandle = ReflectionUtil.getHandle(player);
Object inventoryMenu = ReflectionUtil.getField(playerHandle, ReflectionUtil.supports(19) ? "bT" : ReflectionUtil.supports(17) ? "bU" : "defaultContainer");
int windowId = (int) ReflectionUtil.getField(inventoryMenu, ReflectionUtil.supports(17) ? "j" : "windowId");
ItemStack stack = new ItemStack(ReflectionUtils.supports(13) ? Material.FILLED_MAP : Material.MAP, 1);
ItemStack stack = new ItemStack(ReflectionUtil.supports(13) ? Material.FILLED_MAP : Material.MAP, 1);
Object nmsStack = ReflectionUtil.callMethod(craftStackClass, "asNMSCopy", stack);
Object packet;
if (ReflectionUtils.supports(17)) { //1.17+
int stateId = (int) ReflectionUtil.callMethod(inventoryMenu, ReflectionUtils.supports(18) ? "j" : "getStateId");
if (ReflectionUtil.supports(17)) { //1.17+
int stateId = (int) ReflectionUtil.callMethod(inventoryMenu, ReflectionUtil.supports(18) ? "j" : "getStateId");
packet = ReflectionUtil.callConstructor(setSlotPacketClass,
windowId,
@ -168,7 +167,7 @@ public class MapWrapper {
);
}
ReflectionUtils.sendPacket(player, packet);
ReflectionUtil.sendPacket(player, packet);
}
@Override
@ -178,7 +177,7 @@ public class MapWrapper {
@Override
public void showInHand(Player player, boolean force) {
if (player.getInventory().getItemInMainHand().getType() != (ReflectionUtils.supports(13) ? Material.FILLED_MAP : Material.MAP) && !force)
if (player.getInventory().getItemInMainHand().getType() != (ReflectionUtil.supports(13) ? Material.FILLED_MAP : Material.MAP) && !force)
return;
showInInventory(player, player.getInventory().getHeldItemSlot(), force);
}
@ -195,7 +194,7 @@ public class MapWrapper {
@Override
public void showInFrame(Player player, ItemFrame frame, boolean force) {
if (frame.getItem().getType() != (ReflectionUtils.supports(13) ? Material.FILLED_MAP : Material.MAP) && !force)
if (frame.getItem().getType() != (ReflectionUtil.supports(13) ? Material.FILLED_MAP : Material.MAP) && !force)
return;
showInFrame(player, frame.getEntityId());
}
@ -209,7 +208,7 @@ public class MapWrapper {
public void showInFrame(Player player, int entityId, String debugInfo) {
if (!isViewing(player)) return;
ItemStack stack = new ItemStack(ReflectionUtils.supports(13) ? Material.FILLED_MAP : Material.MAP, 1);
ItemStack stack = new ItemStack(ReflectionUtil.supports(13) ? Material.FILLED_MAP : Material.MAP, 1);
if (debugInfo != null) {
ItemMeta itemMeta = stack.getItemMeta();
itemMeta.setDisplayName(debugInfo);
@ -239,11 +238,11 @@ public class MapWrapper {
@Override
public ItemFrame getItemFrameById(World world, int entityId) {
Object worldHandle = ReflectionUtils.getHandle(world);
Object nmsEntity = ReflectionUtil.callMethod(worldHandle, ReflectionUtils.supports(18) ? "a" : "getEntity");
Object worldHandle = ReflectionUtil.getHandle(world);
Object nmsEntity = ReflectionUtil.callMethod(worldHandle, ReflectionUtil.supports(18) ? "a" : "getEntity");
if (nmsEntity == null) return null;
if (!ReflectionUtils.supports(17)) {
if (!ReflectionUtil.supports(17)) {
nmsEntity = ReflectionUtil.callMethod(nmsEntity, "getBukkitEntity");
}
@ -253,14 +252,14 @@ public class MapWrapper {
private void sendItemFramePacket(Player player, int entityId, ItemStack stack, int mapId) {
Object nmsStack = ReflectionUtil.callMethod(craftStackClass, "asNMSCopy", stack);
Object nbtObject = ReflectionUtil.callMethod(nmsStack, ReflectionUtils.supports(19) ? "v" : ReflectionUtils.supports(18) ? "u" : ReflectionUtils.supports(13) ? "getOrCreateTag" : "getTag");
Object nbtObject = ReflectionUtil.callMethod(nmsStack, ReflectionUtil.supports(19) ? "v" : ReflectionUtil.supports(18) ? "u" : ReflectionUtil.supports(13) ? "getOrCreateTag" : "getTag");
if (!ReflectionUtils.supports(13) && nbtObject == null) { //1.12 has no getOrCreate, call create if null!
if (!ReflectionUtil.supports(13) && nbtObject == null) { //1.12 has no getOrCreate, call create if null!
Object tagCompound = ReflectionUtil.callConstructor(tagCompoundClass);
ReflectionUtil.callMethod(nbtObject, "setTag", tagCompound);
}
ReflectionUtil.callMethod(nbtObject, ReflectionUtils.supports(18) ? "a" : "setInt", "map", mapId);
ReflectionUtil.callMethod(nbtObject, ReflectionUtil.supports(18) ? "a" : "setInt", "map", mapId);
Object dataWatcher = ReflectionUtil.callConstructor(dataWatcherClass, entityClass.cast(null));
Object packet = ReflectionUtil.callConstructor(entityMetadataPacketClass,
@ -270,12 +269,12 @@ public class MapWrapper {
);
List<Object> list = new ArrayList<>();
Object dataWatcherObject = ReflectionUtil.getDeclaredField(entityItemFrameClass, ReflectionUtils.supports(17) ? "ao" : ReflectionUtils.supports(14) ? "ITEM" : ReflectionUtils.supports(13) ? "e" : "c");
Object dataWatcherObject = ReflectionUtil.getDeclaredField(entityItemFrameClass, ReflectionUtil.supports(17) ? "ao" : ReflectionUtil.supports(14) ? "ITEM" : ReflectionUtil.supports(13) ? "e" : "c");
Object dataWatcherItem = ReflectionUtil.callConstructor(dataWatcherItemClass, dataWatcherObject, nmsStack);
list.add(dataWatcherItem);
ReflectionUtil.setDeclaredField(packet, "b", list);
ReflectionUtils.sendPacket(player, packet);
ReflectionUtil.sendPacket(player, packet);
}
};

267
src/main/java/tech/sbdevelopment/mapreflectionapi/utils/ReflectionUtil.java
View file

@ -23,14 +23,22 @@
package tech.sbdevelopment.mapreflectionapi.utils;
import org.bukkit.World;
import org.bukkit.entity.Player;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import javax.annotation.Nonnull;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Objects;
import java.util.concurrent.CompletableFuture;
/**
* <b>ReflectionUtil</b> - Reflection handler for NMS and CraftBukkit.<br>
@ -47,9 +55,131 @@ import java.util.Arrays;
* @version 2.1
*/
public class ReflectionUtil {
/**
* We use reflection mainly to avoid writing a new class for version barrier.
* The version barrier is for NMS that uses the Minecraft version as the main package name.
* <p>
* E.g. EntityPlayer in 1.15 is in the class {@code net.minecraft.server.v1_15_R1}
* but in 1.14 it's in {@code net.minecraft.server.v1_14_R1}
* In order to maintain cross-version compatibility we cannot import these classes.
* <p>
* Performance is not a concern for these specific statically initialized values.
*/
public static final String VERSION;
/**
* The raw minor version number.
* E.g. {@code v1_17_R1} to {@code 17}
*
* @since 4.0.0
*/
public static final int VER = Integer.parseInt(VERSION.substring(1).split("_")[1]);
/**
* Mojang remapped their NMS in 1.17 https://www.spigotmc.org/threads/spigot-bungeecord-1-17.510208/#post-4184317
*/
public static final String
CRAFTBUKKIT = "org.bukkit.craftbukkit." + VERSION + '.',
NMS = v(17, "net.minecraft.").orElse("net.minecraft.server." + VERSION + '.');
/**
* A nullable public accessible field only available in {@code EntityPlayer}.
* This can be null if the player is offline.
*/
private static final MethodHandle PLAYER_CONNECTION;
/**
* Responsible for getting the NMS handler {@code EntityPlayer} object for the player.
* {@code CraftPlayer} is simply a wrapper for {@code EntityPlayer}.
* Used mainly for handling packet related operations.
* <p>
* This is also where the famous player {@code ping} field comes from!
*/
private static final MethodHandle GET_HANDLE;
private static final MethodHandle GET_HANDLE_WORLD;
/**
* Sends a packet to the player's client through a {@code NetworkManager} which
* is where {@code ProtocolLib} controls packets by injecting channels!
*/
private static final MethodHandle SEND_PACKET;
static { // This needs to be right below VERSION because of initialization order.
// This package loop is used to avoid implementation-dependant strings like Bukkit.getVersion() or Bukkit.getBukkitVersion()
// which allows easier testing as well.
String found = null;
for (Package pack : Package.getPackages()) {
String name = pack.getName();
// .v because there are other packages.
if (name.startsWith("org.bukkit.craftbukkit.v")) {
found = pack.getName().split("\\.")[3];
// Just a final guard to make sure it finds this important class.
// As a protection for forge+bukkit implementation that tend to mix versions.
// The real CraftPlayer should exist in the package.
// Note: Doesn't seem to function properly. Will need to separate the version
// handler for NMS and CraftBukkit for softwares like catmc.
try {
Class.forName("org.bukkit.craftbukkit." + found + ".entity.CraftPlayer");
break;
} catch (ClassNotFoundException e) {
found = null;
}
}
}
if (found == null)
throw new IllegalArgumentException("Failed to parse server version. Could not find any package starting with name: 'org.bukkit.craftbukkit.v'");
VERSION = found;
}
static {
Class<?> entityPlayer = getNMSClass("server.level", "EntityPlayer");
Class<?> worldServer = getNMSClass("server.level", "WorldServer");
Class<?> craftPlayer = getCraftClass("entity.CraftPlayer");
Class<?> craftWorld = getCraftClass("CraftWorld");
Class<?> playerConnection = getNMSClass("server.network", "PlayerConnection");
MethodHandles.Lookup lookup = MethodHandles.lookup();
MethodHandle sendPacket = null, getHandle = null, getHandleWorld = null, connection = null;
try {
connection = lookup.findGetter(entityPlayer,
v(17, "b").orElse("playerConnection"), playerConnection);
getHandle = lookup.findVirtual(craftPlayer, "getHandle", MethodType.methodType(entityPlayer));
getHandleWorld = lookup.findVirtual(craftWorld, "getHandle", MethodType.methodType(worldServer));
sendPacket = lookup.findVirtual(playerConnection,
v(18, "a").orElse("sendPacket"),
MethodType.methodType(void.class, getNMSClass("network.protocol", "Packet")));
} catch (NoSuchMethodException | NoSuchFieldException | IllegalAccessException ex) {
ex.printStackTrace();
}
PLAYER_CONNECTION = connection;
SEND_PACKET = sendPacket;
GET_HANDLE = getHandle;
GET_HANDLE_WORLD = getHandleWorld;
}
private ReflectionUtil() {
}
/**
* This method is purely for readability.
* No performance is gained.
*
* @since 5.0.0
*/
public static <T> VersionHandler<T> v(int version, T handle) {
return new VersionHandler<>(version, handle);
}
/**
* Checks whether the server version is equal or greater than the given version.
*
* @param version the version to compare the server version with.
* @return true if the version is equal or newer, otherwise false.
* @since 4.0.0
*/
public static boolean supports(int version) {
return VER >= version;
}
private static Class<?> wrapperToPrimitive(Class<?> clazz) {
if (clazz == Boolean.class) return boolean.class;
if (clazz == Integer.class) return int.class;
@ -162,4 +292,141 @@ public class ReflectionUtil {
ex.printStackTrace();
}
}
/**
* Get a NMS (net.minecraft.server) class which accepts a package for 1.17 compatibility.
*
* @param newPackage the 1.17 package name.
* @param name the name of the class.
* @return the NMS class or null if not found.
* @since 4.0.0
*/
@javax.annotation.Nullable
public static Class<?> getNMSClass(@Nonnull String newPackage, @Nonnull String name) {
if (supports(17)) name = newPackage + '.' + name;
return getNMSClass(name);
}
/**
* Get a NMS (net.minecraft.server) class.
*
* @param name the name of the class.
* @return the NMS class or null if not found.
* @since 1.0.0
*/
@javax.annotation.Nullable
public static Class<?> getNMSClass(@Nonnull String name) {
try {
return Class.forName(NMS + name);
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
return null;
}
}
/**
* Sends a packet to the player asynchronously if they're online.
* Packets are thread-safe.
*
* @param player the player to send the packet to.
* @param packets the packets to send.
* @return the async thread handling the packet.
* @see #sendPacketSync(Player, Object...)
* @since 1.0.0
*/
@Nonnull
public static CompletableFuture<Void> sendPacket(@Nonnull Player player, @Nonnull Object... packets) {
return CompletableFuture.runAsync(() -> sendPacketSync(player, packets))
.exceptionally(ex -> {
ex.printStackTrace();
return null;
});
}
/**
* Sends a packet to the player synchronously if they're online.
*
* @param player the player to send the packet to.
* @param packets the packets to send.
* @see #sendPacket(Player, Object...)
* @since 2.0.0
*/
public static void sendPacketSync(@Nonnull Player player, @Nonnull Object... packets) {
try {
Object handle = GET_HANDLE.invoke(player);
Object connection = PLAYER_CONNECTION.invoke(handle);
// Checking if the connection is not null is enough. There is no need to check if the player is online.
if (connection != null) {
for (Object packet : packets) SEND_PACKET.invoke(connection, packet);
}
} catch (Throwable throwable) {
throwable.printStackTrace();
}
}
@javax.annotation.Nullable
public static Object getHandle(@Nonnull Player player) {
Objects.requireNonNull(player, "Cannot get handle of null player");
try {
return GET_HANDLE.invoke(player);
} catch (Throwable throwable) {
throwable.printStackTrace();
return null;
}
}
@javax.annotation.Nullable
public static Object getHandle(@Nonnull World world) {
Objects.requireNonNull(world, "Cannot get handle of null world");
try {
return GET_HANDLE_WORLD.invoke(world);
} catch (Throwable throwable) {
throwable.printStackTrace();
return null;
}
}
/**
* Get a CraftBukkit (org.bukkit.craftbukkit) class.
*
* @param name the name of the class to load.
* @return the CraftBukkit class or null if not found.
* @since 1.0.0
*/
@javax.annotation.Nullable
public static Class<?> getCraftClass(@Nonnull String name) {
try {
return Class.forName(CRAFTBUKKIT + name);
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
return null;
}
}
public static final class VersionHandler<T> {
private int version;
private T handle;
private VersionHandler(int version, T handle) {
if (supports(version)) {
this.version = version;
this.handle = handle;
}
}
public VersionHandler<T> v(int version, T handle) {
if (version == this.version)
throw new IllegalArgumentException("Cannot have duplicate version handles for version: " + version);
if (version > this.version && supports(version)) {
this.version = version;
this.handle = handle;
}
return this;
}
public T orElse(T handle) {
return this.version == 0 ? handle : this.handle;
}
}
}

382
src/main/java/tech/sbdevelopment/mapreflectionapi/utils/ReflectionUtils.java
View file

@ -1,382 +0,0 @@
/*
* This file is part of MapReflectionAPI.
* Copyright (c) 2022 inventivetalent / SBDevelopment - All Rights Reserved
*
* 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.
*/
package tech.sbdevelopment.mapreflectionapi.utils;
import org.bukkit.World;
import org.bukkit.entity.Player;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.util.Objects;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletableFuture;
/**
* <b>ReflectionUtils</b> - Reflection handler for NMS and CraftBukkit.<br>
* Caches the packet related methods and is asynchronous.
* <p>
* This class does not handle null checks as most of the requests are from the
* other utility classes that already handle null checks.
* <p>
* <a href="https://wiki.vg/Protocol">Clientbound Packets</a> are considered fake
* updates to the client without changing the actual data. Since all the data is handled
* by the server.
* <p>
* A useful resource used to compare mappings is <a href="https://minidigger.github.io/MiniMappingViewer/#/spigot">Mini's Mapping Viewer</a>
*
* @author Crypto Morin
* @version 6.0.1
*/
public final class ReflectionUtils {
/**
* We use reflection mainly to avoid writing a new class for version barrier.
* The version barrier is for NMS that uses the Minecraft version as the main package name.
* <p>
* E.g. EntityPlayer in 1.15 is in the class {@code net.minecraft.server.v1_15_R1}
* but in 1.14 it's in {@code net.minecraft.server.v1_14_R1}
* In order to maintain cross-version compatibility we cannot import these classes.
* <p>
* Performance is not a concern for these specific statically initialized values.
*/
public static final String VERSION;
static { // This needs to be right below VERSION because of initialization order.
// This package loop is used to avoid implementation-dependant strings like Bukkit.getVersion() or Bukkit.getBukkitVersion()
// which allows easier testing as well.
String found = null;
for (Package pack : Package.getPackages()) {
String name = pack.getName();
// .v because there are other packages.
if (name.startsWith("org.bukkit.craftbukkit.v")) {
found = pack.getName().split("\\.")[3];
// Just a final guard to make sure it finds this important class.
// As a protection for forge+bukkit implementation that tend to mix versions.
// The real CraftPlayer should exist in the package.
// Note: Doesn't seem to function properly. Will need to separate the version
// handler for NMS and CraftBukkit for softwares like catmc.
try {
Class.forName("org.bukkit.craftbukkit." + found + ".entity.CraftPlayer");
break;
} catch (ClassNotFoundException e) {
found = null;
}
}
}
if (found == null)
throw new IllegalArgumentException("Failed to parse server version. Could not find any package starting with name: 'org.bukkit.craftbukkit.v'");
VERSION = found;
}
/**
* The raw minor version number.
* E.g. {@code v1_17_R1} to {@code 17}
*
* @since 4.0.0
*/
public static final int VER = Integer.parseInt(VERSION.substring(1).split("_")[1]);
/**
* Mojang remapped their NMS in 1.17 https://www.spigotmc.org/threads/spigot-bungeecord-1-17.510208/#post-4184317
*/
public static final String
CRAFTBUKKIT = "org.bukkit.craftbukkit." + VERSION + '.',
NMS = v(17, "net.minecraft.").orElse("net.minecraft.server." + VERSION + '.');
/**
* A nullable public accessible field only available in {@code EntityPlayer}.
* This can be null if the player is offline.
*/
private static final MethodHandle PLAYER_CONNECTION;
/**
* Responsible for getting the NMS handler {@code EntityPlayer} object for the player.
* {@code CraftPlayer} is simply a wrapper for {@code EntityPlayer}.
* Used mainly for handling packet related operations.
* <p>
* This is also where the famous player {@code ping} field comes from!
*/
private static final MethodHandle GET_HANDLE;
private static final MethodHandle GET_HANDLE_WORLD;
/**
* Sends a packet to the player's client through a {@code NetworkManager} which
* is where {@code ProtocolLib} controls packets by injecting channels!
*/
private static final MethodHandle SEND_PACKET;
static {
Class<?> entityPlayer = getNMSClass("server.level", "EntityPlayer");
Class<?> worldServer = getNMSClass("server.level", "WorldServer");
Class<?> craftPlayer = getCraftClass("entity.CraftPlayer");
Class<?> craftWorld = getCraftClass("CraftWorld");
Class<?> playerConnection = getNMSClass("server.network", "PlayerConnection");
MethodHandles.Lookup lookup = MethodHandles.lookup();
MethodHandle sendPacket = null, getHandle = null, getHandleWorld = null, connection = null;
try {
connection = lookup.findGetter(entityPlayer,
v(17, "b").orElse("playerConnection"), playerConnection);
getHandle = lookup.findVirtual(craftPlayer, "getHandle", MethodType.methodType(entityPlayer));
getHandleWorld = lookup.findVirtual(craftWorld, "getHandle", MethodType.methodType(worldServer));
sendPacket = lookup.findVirtual(playerConnection,
v(18, "a").orElse("sendPacket"),
MethodType.methodType(void.class, getNMSClass("network.protocol", "Packet")));
} catch (NoSuchMethodException | NoSuchFieldException | IllegalAccessException ex) {
ex.printStackTrace();
}
PLAYER_CONNECTION = connection;
SEND_PACKET = sendPacket;
GET_HANDLE = getHandle;
GET_HANDLE_WORLD = getHandleWorld;
}
private ReflectionUtils() {
}
/**
* This method is purely for readability.
* No performance is gained.
*
* @since 5.0.0
*/
public static <T> VersionHandler<T> v(int version, T handle) {
return new VersionHandler<>(version, handle);
}
public static <T> CallableVersionHandler<T> v(int version, Callable<T> handle) {
return new CallableVersionHandler<>(version, handle);
}
/**
* Checks whether the server version is equal or greater than the given version.
*
* @param version the version to compare the server version with.
* @return true if the version is equal or newer, otherwise false.
* @since 4.0.0
*/
public static boolean supports(int version) {
return VER >= version;
}
/**
* Get a NMS (net.minecraft.server) class which accepts a package for 1.17 compatibility.
*
* @param newPackage the 1.17 package name.
* @param name the name of the class.
* @return the NMS class or null if not found.
* @since 4.0.0
*/
@Nullable
public static Class<?> getNMSClass(@Nonnull String newPackage, @Nonnull String name) {
if (supports(17)) name = newPackage + '.' + name;
return getNMSClass(name);
}
/**
* Get a NMS (net.minecraft.server) class.
*
* @param name the name of the class.
* @return the NMS class or null if not found.
* @since 1.0.0
*/
@Nullable
public static Class<?> getNMSClass(@Nonnull String name) {
try {
return Class.forName(NMS + name);
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
return null;
}
}
/**
* Sends a packet to the player asynchronously if they're online.
* Packets are thread-safe.
*
* @param player the player to send the packet to.
* @param packets the packets to send.
* @return the async thread handling the packet.
* @see #sendPacketSync(Player, Object...)
* @since 1.0.0
*/
@Nonnull
public static CompletableFuture<Void> sendPacket(@Nonnull Player player, @Nonnull Object... packets) {
return CompletableFuture.runAsync(() -> sendPacketSync(player, packets))
.exceptionally(ex -> {
ex.printStackTrace();
return null;
});
}
/**
* Sends a packet to the player synchronously if they're online.
*
* @param player the player to send the packet to.
* @param packets the packets to send.
* @see #sendPacket(Player, Object...)
* @since 2.0.0
*/
public static void sendPacketSync(@Nonnull Player player, @Nonnull Object... packets) {
try {
Object handle = GET_HANDLE.invoke(player);
Object connection = PLAYER_CONNECTION.invoke(handle);
// Checking if the connection is not null is enough. There is no need to check if the player is online.
if (connection != null) {
for (Object packet : packets) SEND_PACKET.invoke(connection, packet);
}
} catch (Throwable throwable) {
throwable.printStackTrace();
}
}
@Nullable
public static Object getHandle(@Nonnull Player player) {
Objects.requireNonNull(player, "Cannot get handle of null player");
try {
return GET_HANDLE.invoke(player);
} catch (Throwable throwable) {
throwable.printStackTrace();
return null;
}
}
@Nullable
public static Object getHandle(@Nonnull World world) {
Objects.requireNonNull(world, "Cannot get handle of null world");
try {
return GET_HANDLE_WORLD.invoke(world);
} catch (Throwable throwable) {
throwable.printStackTrace();
return null;
}
}
@Nullable
public static Object getConnection(@Nonnull Player player) {
Objects.requireNonNull(player, "Cannot get connection of null player");
try {
Object handle = GET_HANDLE.invoke(player);
return PLAYER_CONNECTION.invoke(handle);
} catch (Throwable throwable) {
throwable.printStackTrace();
return null;
}
}
/**
* Get a CraftBukkit (org.bukkit.craftbukkit) class.
*
* @param name the name of the class to load.
* @return the CraftBukkit class or null if not found.
* @since 1.0.0
*/
@Nullable
public static Class<?> getCraftClass(@Nonnull String name) {
try {
return Class.forName(CRAFTBUKKIT + name);
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
return null;
}
}
public static Class<?> getArrayClass(String clazz, boolean nms) {
clazz = "[L" + (nms ? NMS : CRAFTBUKKIT) + clazz + ';';
try {
return Class.forName(clazz);
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
return null;
}
}
public static Class<?> toArrayClass(Class<?> clazz) {
try {
return Class.forName("[L" + clazz.getName() + ';');
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
return null;
}
}
public static final class VersionHandler<T> {
private int version;
private T handle;
private VersionHandler(int version, T handle) {
if (supports(version)) {
this.version = version;
this.handle = handle;
}
}
public VersionHandler<T> v(int version, T handle) {
if (version == this.version)
throw new IllegalArgumentException("Cannot have duplicate version handles for version: " + version);
if (version > this.version && supports(version)) {
this.version = version;
this.handle = handle;
}
return this;
}
public T orElse(T handle) {
return this.version == 0 ? handle : this.handle;
}
}
public static final class CallableVersionHandler<T> {
private int version;
private Callable<T> handle;
private CallableVersionHandler(int version, Callable<T> handle) {
if (supports(version)) {
this.version = version;
this.handle = handle;
}
}
public CallableVersionHandler<T> v(int version, Callable<T> handle) {
if (version == this.version)
throw new IllegalArgumentException("Cannot have duplicate version handles for version: " + version);
if (version > this.version && supports(version)) {
this.version = version;
this.handle = handle;
}
return this;
}
public T orElse(Callable<T> handle) {
try {
return (this.version == 0 ? handle : this.handle).call();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
}