Don't send json text on MC 1.7

bukkit/src/main/java/me/lucko/luckperms/bukkit/compat/BukkitJsonMessageHandler.java

@@ -22,7 +22,6 @@
 
 package me.lucko.luckperms.bukkit.compat;
 
-import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
 
 import java.lang.reflect.Constructor;
@@ -58,7 +57,7 @@ public class BukkitJsonMessageHandler {
             }
         }
 
-        Class<?> packetChatClass = Class.forName(getVersionedClassName("PacketPlayOutChat"));
+        Class<?> packetChatClass = ReflectionUtil.nmsClass("PacketPlayOutChat");
         Constructor[] packetConstructors = packetChatClass.getDeclaredConstructors();
         for (Constructor c : packetConstructors) {
             Class<?>[] parameters = c.getParameterTypes();
@@ -68,30 +67,19 @@ public class BukkitJsonMessageHandler {
             }
         }
 
-        Class<?> baseComponentClass = Class.forName(getVersionedClassName("IChatBaseComponent"));
-        Class<?> chatSerializerClass = baseComponentClass.getClasses()[0];
+        Class<?> baseComponentClass = ReflectionUtil.nmsClass("IChatBaseComponent");
+        Class<?> chatSerializerClass;
+
+        if (baseComponentClass.getClasses().length > 0) {
+            chatSerializerClass = baseComponentClass.getClasses()[0];
+        } else {
+            // 1.7 class is here instead.
+            chatSerializerClass = ReflectionUtil.nmsClass("ChatSerializer");
+        }
 
         SERIALIZE_METHOD = chatSerializerClass.getDeclaredMethod("a", String.class);
     }
 
-    private static String getVersionedClassName(String className) {
-        Class server = Bukkit.getServer().getClass();
-        if (!server.getSimpleName().equals("CraftServer")) {
-            throw new RuntimeException("Couldn't reflect into server " + server);
-        }
-
-        String version;
-        if (server.getName().equals("org.bukkit.craftbukkit.CraftServer")) {
-            // Non versioned class
-            version = ".";
-        } else {
-            version = server.getName().substring("org.bukkit.craftbukkit".length());
-            version = version.substring(0, version.length() - "CraftServer".length());
-        }
-
-        return "net.minecraft.server" + version + className;
-    }
-
     private static synchronized boolean trySetup(Object player) {
         if (setup) return true;
         if (triedAndFailed) return false;

bukkit/src/main/java/me/lucko/luckperms/bukkit/compat/MessageHandler.java

@@ -37,7 +37,7 @@ public class MessageHandler {
     }
 
     public void sendJsonMessage(CommandSender sender, FancyMessage message) {
-        if (sender instanceof Player) {
+        if (ReflectionUtil.isChatCompatible() && sender instanceof Player) {
             Player player = (Player) sender;
             String json = message.toJSONString();
 

bukkit/src/main/java/me/lucko/luckperms/bukkit/compat/ReflectionUtil.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2016 Lucko (Luck) <luck@lucko.me>
+ *
+ *  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 me.lucko.luckperms.bukkit.compat;
+
+import lombok.experimental.UtilityClass;
+
+import org.bukkit.Bukkit;
+
+@UtilityClass
+public class ReflectionUtil {
+    private static final String SERVER_VERSION = _getServerVersion();
+    private static final boolean CHAT_COMPATIBLE = !SERVER_VERSION.startsWith(".v1_7_");
+
+    private static String _getServerVersion() {
+        Class<?> server = Bukkit.getServer().getClass();
+        if (!server.getSimpleName().equals("CraftServer")) {
+            return ".";
+        }
+        if (server.getName().equals("org.bukkit.craftbukkit.CraftServer")) {
+            // Non versioned class
+            return ".";
+        } else {
+            String version = server.getName().substring("org.bukkit.craftbukkit".length());
+            return version.substring(0, version.length() - "CraftServer".length());
+        }
+    }
+
+    public static String getServerVersion() {
+        return SERVER_VERSION;
+    }
+
+    public static boolean isChatCompatible() {
+        return CHAT_COMPATIBLE;
+    }
+
+    public static String nms(String className) {
+        return "net.minecraft.server" + getServerVersion() + className;
+    }
+
+    public static Class<?> nmsClass(String className) throws ClassNotFoundException {
+        return Class.forName(nms(className));
+    }
+
+    public static String obc(String className) {
+        return "org.bukkit.craftbukkit" + getServerVersion() + className;
+    }
+
+    public static Class<?> obcClass(String className) throws ClassNotFoundException {
+        return Class.forName(obc(className));
+    }
+}