--- a/net/minecraft/server/MinecraftServer.java
+++ b/net/minecraft/server/MinecraftServer.java
@@ -54,6 +54,14 @@
 import org.apache.commons.lang3.Validate;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+// CraftBukkit start
+import jline.console.ConsoleReader;
+import joptsimple.OptionSet;
+import org.bukkit.Bukkit;
+import org.bukkit.craftbukkit.CraftServer;
+import org.bukkit.craftbukkit.Main;
+import org.bukkit.event.server.ServerLoadEvent;
+// CraftBukkit end
 
 public abstract class MinecraftServer implements IAsyncTaskHandler, IMojangStatistics, ICommandListener, Runnable {
 
@@ -124,7 +132,21 @@
     private boolean forceUpgrade;
     private float ap;
 
-    public MinecraftServer(@Nullable File file, Proxy proxy, DataFixer datafixer, CommandDispatcher commanddispatcher, YggdrasilAuthenticationService yggdrasilauthenticationservice, MinecraftSessionService minecraftsessionservice, GameProfileRepository gameprofilerepository, UserCache usercache) {
+    // CraftBukkit start
+    public org.bukkit.craftbukkit.CraftServer server;
+    public OptionSet options;
+    public org.bukkit.command.ConsoleCommandSender console;
+    public org.bukkit.command.RemoteConsoleCommandSender remoteConsole;
+    public ConsoleReader reader;
+    public static int currentTick = (int) (System.currentTimeMillis() / 50);
+    public final Thread primaryThread;
+    public java.util.Queue<Runnable> processQueue = new java.util.concurrent.ConcurrentLinkedQueue<Runnable>();
+    public int autosavePeriod;
+    public File bukkitDataPackFolder;
+    public CommandDispatcher vanillaCommandDispatcher;
+    // CraftBukkit end
+
+    public MinecraftServer(OptionSet options, Proxy proxy, DataFixer datafixer, CommandDispatcher commanddispatcher, YggdrasilAuthenticationService yggdrasilauthenticationservice, MinecraftSessionService minecraftsessionservice, GameProfileRepository gameprofilerepository, UserCache usercache) {
         this.ac = new ResourceManager(EnumResourcePackType.SERVER_DATA);
         this.resourcePackRepository = new ResourcePackRepository<>(ResourcePackLoader::new);
         this.ag = new CraftingManager();
@@ -135,22 +157,51 @@
         this.al = new AdvancementDataWorld();
         this.am = new CustomFunctionData(this);
         this.c = proxy;
-        this.commandDispatcher = commanddispatcher;
+        this.commandDispatcher = this.vanillaCommandDispatcher = commanddispatcher; // CraftBukkit
         this.U = yggdrasilauthenticationservice;
         this.V = minecraftsessionservice;
         this.W = gameprofilerepository;
         this.X = usercache;
-        this.universe = file;
-        this.serverConnection = file == null ? null : new ServerConnection(this);
-        this.convertable = file == null ? null : new WorldLoaderServer(file.toPath(), file.toPath().resolve("../backups"), datafixer);
+        // this.universe = file; // CraftBukkit
+        this.serverConnection = new ServerConnection(this); // CraftBukkit
+        // this.convertable = file == null ? null : new WorldLoaderServer(file.toPath(), file.toPath().resolve("../backups"), datafixer); // CraftBukkit - moved to DedicatedServer.init
         this.dataConverterManager = datafixer;
         this.ac.a((IResourcePackListener) this.ah);
         this.ac.a((IResourcePackListener) this.ag);
         this.ac.a((IResourcePackListener) this.ak);
         this.ac.a((IResourcePackListener) this.am);
         this.ac.a((IResourcePackListener) this.al);
+        // CraftBukkit start
+        this.options = options;
+        // Try to see if we're actually running in a terminal, disable jline if not
+        if (System.console() == null && System.getProperty("jline.terminal") == null) {
+            System.setProperty("jline.terminal", "jline.UnsupportedTerminal");
+            Main.useJline = false;
+        }
+
+        try {
+            reader = new ConsoleReader(System.in, System.out);
+            reader.setExpandEvents(false); // Avoid parsing exceptions for uncommonly used event designators
+        } catch (Throwable e) {
+            try {
+                // Try again with jline disabled for Windows users without C++ 2008 Redistributable
+                System.setProperty("jline.terminal", "jline.UnsupportedTerminal");
+                System.setProperty("user.language", "en");
+                Main.useJline = false;
+                reader = new ConsoleReader(System.in, System.out);
+                reader.setExpandEvents(false);
+            } catch (IOException ex) {
+                LOGGER.warn((String) null, ex);
+            }
+        }
+        Runtime.getRuntime().addShutdownHook(new org.bukkit.craftbukkit.util.ServerShutdownThread(this));
+
+        this.serverThread = primaryThread = new Thread(this, "Server thread"); // Moved from main
     }
 
+    public abstract PropertyManager getPropertyManager();
+    // CraftBukkit end
+
     public abstract boolean init() throws IOException;
 
     public void convertWorld(String s) {
@@ -175,11 +226,11 @@
         }
 
         if (this.forceUpgrade) {
-            MinecraftServer.LOGGER.info("Forcing world upgrade!");
-            WorldData worlddata = this.getConvertable().c(this.getWorld());
+            MinecraftServer.LOGGER.info("Forcing world upgrade! {}", s); // CraftBukkit
+            WorldData worlddata = this.getConvertable().c(s); // CraftBukkit
 
             if (worlddata != null) {
-                WorldUpgrader worldupgrader = new WorldUpgrader(this.getWorld(), this.getConvertable(), worlddata);
+                WorldUpgrader worldupgrader = new WorldUpgrader(s, this.getConvertable(), worlddata); // CraftBukkit
                 IChatBaseComponent ichatbasecomponent = null;
 
                 while (!worldupgrader.b()) {
@@ -218,8 +269,9 @@
     }
 
     public void a(String s, String s1, long i, WorldType worldtype, JsonElement jsonelement) {
-        this.convertWorld(s);
+        // this.convertWorld(s); // CraftBukkit - moved down
         this.b((IChatBaseComponent) (new ChatMessage("menu.loadingLevel", new Object[0])));
+        /* CraftBukkit start - Remove ticktime arrays and worldsettings
         IDataManager idatamanager = this.getConvertable().a(s, this);
 
         this.a(this.getWorld(), idatamanager);
@@ -244,54 +296,144 @@
         }
 
         this.a(idatamanager.getDirectory(), worlddata);
-        PersistentCollection persistentcollection = new PersistentCollection(idatamanager);
+        */
+        int worldCount = 3;
 
-        this.a(idatamanager, persistentcollection, worlddata, worldsettings);
-        this.a(this.getDifficulty());
-        this.a(persistentcollection);
-    }
+        for (int j = 0; j < worldCount; ++j) {
+            WorldServer world;
+            WorldData worlddata;
+            byte dimension = 0;
+
+            if (j == 1) {
+                if (getAllowNether()) {
+                    dimension = -1;
+                } else {
+                    continue;
+                }
+            }
 
-    protected void a(IDataManager idatamanager, PersistentCollection persistentcollection, WorldData worlddata, WorldSettings worldsettings) {
-        if (this.L()) {
-            this.worldServer.put(DimensionManager.OVERWORLD, (new DemoWorldServer(this, idatamanager, persistentcollection, worlddata, DimensionManager.OVERWORLD, this.methodProfiler)).i_());
-        } else {
-            this.worldServer.put(DimensionManager.OVERWORLD, (new WorldServer(this, idatamanager, persistentcollection, worlddata, DimensionManager.OVERWORLD, this.methodProfiler)).i_());
-        }
+            if (j == 2) {
+                if (server.getAllowEnd()) {
+                    dimension = 1;
+                } else {
+                    continue;
+                }
+            }
+
+            String worldType = org.bukkit.World.Environment.getEnvironment(dimension).toString().toLowerCase();
+            String name = (dimension == 0) ? s : s + "_" + worldType;
+            this.convertWorld(name); // Run conversion now
+
+            org.bukkit.generator.ChunkGenerator gen = this.server.getGenerator(name);
+            WorldSettings worldsettings = new WorldSettings(i, this.getGamemode(), this.getGenerateStructures(), this.isHardcore(), worldtype);
+            worldsettings.setGeneratorSettings(jsonelement);
+
+            if (j == 0) {
+                IDataManager idatamanager = new ServerNBTManager(server.getWorldContainer(), s1, this, this.dataConverterManager);
+                worlddata = idatamanager.getWorldData();
+                if (worlddata == null) {
+                    worlddata = new WorldData(worldsettings, s1);
+                }
+                worlddata.checkName(s1); // CraftBukkit - Migration did not rewrite the level.dat; This forces 1.8 to take the last loaded world as respawn (in this case the end)
+                this.a(idatamanager.getDirectory(), worlddata);
+                PersistentCollection persistentcollection = new PersistentCollection(idatamanager);
 
-        WorldServer worldserver = this.getWorldServer(DimensionManager.OVERWORLD);
+                if (this.L()) {
+                    world = (WorldServer) (new DemoWorldServer(this, idatamanager, persistentcollection, worlddata, DimensionManager.OVERWORLD, this.methodProfiler)).i_();
+                } else {
+                    world = (WorldServer) (new WorldServer(this, idatamanager, persistentcollection, worlddata, DimensionManager.OVERWORLD, this.methodProfiler, org.bukkit.World.Environment.getEnvironment(dimension), gen)).i_();
+                }
 
-        worldserver.a(worldsettings);
-        worldserver.addIWorldAccess(new WorldManager(this, worldserver));
-        if (!this.H()) {
-            worldserver.getWorldData().setGameType(this.getGamemode());
-        }
+                world.a(worldsettings);
+                this.server.scoreboardManager = new org.bukkit.craftbukkit.scoreboard.CraftScoreboardManager(this, world.getScoreboard());
+            } else {
+                String dim = "DIM" + dimension;
 
-        SecondaryWorldServer secondaryworldserver = (new SecondaryWorldServer(this, idatamanager, DimensionManager.NETHER, worldserver, this.methodProfiler)).i_();
+                File newWorld = new File(new File(name), dim);
+                File oldWorld = new File(new File(s), dim);
 
-        this.worldServer.put(DimensionManager.NETHER, secondaryworldserver);
-        secondaryworldserver.addIWorldAccess(new WorldManager(this, secondaryworldserver));
-        if (!this.H()) {
-            secondaryworldserver.getWorldData().setGameType(this.getGamemode());
-        }
+                if ((!newWorld.isDirectory()) && (oldWorld.isDirectory())) {
+                    MinecraftServer.LOGGER.info("---- Migration of old " + worldType + " folder required ----");
+                    MinecraftServer.LOGGER.info("Unfortunately due to the way that Minecraft implemented multiworld support in 1.6, Bukkit requires that you move your " + worldType + " folder to a new location in order to operate correctly.");
+                    MinecraftServer.LOGGER.info("We will move this folder for you, but it will mean that you need to move it back should you wish to stop using Bukkit in the future.");
+                    MinecraftServer.LOGGER.info("Attempting to move " + oldWorld + " to " + newWorld + "...");
+
+                    if (newWorld.exists()) {
+                        MinecraftServer.LOGGER.warn("A file or folder already exists at " + newWorld + "!");
+                        MinecraftServer.LOGGER.info("---- Migration of old " + worldType + " folder failed ----");
+                    } else if (newWorld.getParentFile().mkdirs()) {
+                        if (oldWorld.renameTo(newWorld)) {
+                            MinecraftServer.LOGGER.info("Success! To restore " + worldType + " in the future, simply move " + newWorld + " to " + oldWorld);
+                            // Migrate world data too.
+                            try {
+                                com.google.common.io.Files.copy(new File(new File(s), "level.dat"), new File(new File(name), "level.dat"));
+                                org.apache.commons.io.FileUtils.copyDirectory(new File(new File(s), "data"), new File(new File(name), "data"));
+                            } catch (IOException exception) {
+                                MinecraftServer.LOGGER.warn("Unable to migrate world data.");
+                            }
+                            MinecraftServer.LOGGER.info("---- Migration of old " + worldType + " folder complete ----");
+                        } else {
+                            MinecraftServer.LOGGER.warn("Could not move folder " + oldWorld + " to " + newWorld + "!");
+                            MinecraftServer.LOGGER.info("---- Migration of old " + worldType + " folder failed ----");
+                        }
+                    } else {
+                        MinecraftServer.LOGGER.warn("Could not create path for " + newWorld + "!");
+                        MinecraftServer.LOGGER.info("---- Migration of old " + worldType + " folder failed ----");
+                    }
+                }
 
-        SecondaryWorldServer secondaryworldserver1 = (new SecondaryWorldServer(this, idatamanager, DimensionManager.THE_END, worldserver, this.methodProfiler)).i_();
+                IDataManager idatamanager = new ServerNBTManager(server.getWorldContainer(), name, this, this.dataConverterManager);
+                // world =, b0 to dimension, s1 to name, added Environment and gen
+                worlddata = idatamanager.getWorldData();
+                if (worlddata == null) {
+                    worlddata = new WorldData(worldsettings, name);
+                }
+                worlddata.checkName(name); // CraftBukkit - Migration did not rewrite the level.dat; This forces 1.8 to take the last loaded world as respawn (in this case the end)
+                world = (WorldServer) new SecondaryWorldServer(this, idatamanager, DimensionManager.a(dimension), this.getWorldServer(DimensionManager.OVERWORLD), this.methodProfiler, worlddata, org.bukkit.World.Environment.getEnvironment(dimension), gen).i_();
+            }
 
-        this.worldServer.put(DimensionManager.THE_END, secondaryworldserver1);
-        secondaryworldserver1.addIWorldAccess(new WorldManager(this, secondaryworldserver1));
-        if (!this.H()) {
-            secondaryworldserver1.getWorldData().setGameType(this.getGamemode());
-        }
+            this.server.getPluginManager().callEvent(new org.bukkit.event.world.WorldInitEvent(world.getWorld()));
+
+            world.addIWorldAccess(new WorldManager(this, world));
+            if (!this.H()) {
+                world.getWorldData().setGameType(this.getGamemode());
+            }
 
-        this.getPlayerList().setPlayerFileData(worldserver);
-        if (worlddata.P() != null) {
-            this.getBossBattleCustomData().a(worlddata.P());
+            this.worldServer.put(world.dimension, world);
+            this.getPlayerList().setPlayerFileData(world);
+
+            if (worlddata.P() != null) {
+                this.getBossBattleCustomData().a(worlddata.P());
+            }
         }
+        this.a(this.getDifficulty());
+        this.a(this.getWorldServer(DimensionManager.OVERWORLD).worldMaps);
+        // CraftBukkit end
 
     }
 
     protected void a(File file, WorldData worlddata) {
         this.resourcePackRepository.a((ResourcePackSource) (new ResourcePackSourceVanilla()));
         this.resourcePackFolder = new ResourcePackSourceFolder(new File(file, "datapacks"));
+        // CraftBukkit start
+        bukkitDataPackFolder = new File(new File(file, "datapacks"), "bukkit");
+        if (!bukkitDataPackFolder.exists()) {
+            bukkitDataPackFolder.mkdirs();
+        }
+        File mcMeta = new File(bukkitDataPackFolder, "pack.mcmeta");
+        if (!mcMeta.exists()) {
+            try {
+                com.google.common.io.Files.write("{\n"
+                        + "    \"pack\": {\n"
+                        + "        \"description\": \"Data pack for resources provided by Bukkit plugins\",\n"
+                        + "        \"pack_format\": 1\n"
+                        + "    }\n"
+                        + "}", mcMeta, com.google.common.base.Charsets.UTF_8);
+            } catch (IOException ex) {
+                throw new RuntimeException("Could not initialize Bukkit datapack", ex);
+            }
+        }
+        // CraftBukkit end
         this.resourcePackRepository.a((ResourcePackSource) this.resourcePackFolder);
         this.resourcePackRepository.a();
         List<ResourcePackLoader> list = Lists.newArrayList();
@@ -320,42 +462,52 @@
         boolean flag4 = true;
 
         this.b((IChatBaseComponent) (new ChatMessage("menu.generatingTerrain", new Object[0])));
-        WorldServer worldserver = this.getWorldServer(DimensionManager.OVERWORLD);
 
-        MinecraftServer.LOGGER.info("Preparing start region for dimension " + DimensionManager.a(worldserver.worldProvider.getDimensionManager()));
-        BlockPosition blockposition = worldserver.getSpawn();
-        List<ChunkCoordIntPair> list = Lists.newArrayList();
-        Set<ChunkCoordIntPair> set = Sets.newConcurrentHashSet();
+        // CraftBukkit start - fire WorldLoadEvent and handle whether or not to keep the spawn in memory
         Stopwatch stopwatch = Stopwatch.createStarted();
-
-        for (int i = -192; i <= 192 && this.isRunning(); i += 16) {
-            for (int j = -192; j <= 192 && this.isRunning(); j += 16) {
-                list.add(new ChunkCoordIntPair(blockposition.getX() + i >> 4, blockposition.getZ() + j >> 4));
+        for (WorldServer worldserver : this.getWorlds()) {
+            MinecraftServer.LOGGER.info("Preparing start region for level " + worldserver.dimension + " (Seed: " + worldserver.getSeed() + ")");
+            if (!worldserver.getWorld().getKeepSpawnInMemory()) {
+                continue;
             }
 
-            CompletableFuture completablefuture = worldserver.getChunkProvider().a((Iterable) list, (chunk) -> {
-                set.add(chunk.getPos());
-            });
+            BlockPosition blockposition = worldserver.getSpawn();
+            List<ChunkCoordIntPair> list = Lists.newArrayList();
+            Set<ChunkCoordIntPair> set = Sets.newConcurrentHashSet();
+
+            for (int i = -192; i <= 192 && this.isRunning(); i += 16) {
+                for (int j = -192; j <= 192 && this.isRunning(); j += 16) {
+                    list.add(new ChunkCoordIntPair(blockposition.getX() + i >> 4, blockposition.getZ() + j >> 4));
+                }
 
-            while (!completablefuture.isDone()) {
-                try {
-                    completablefuture.get(1L, TimeUnit.SECONDS);
-                } catch (InterruptedException interruptedexception) {
-                    throw new RuntimeException(interruptedexception);
-                } catch (ExecutionException executionexception) {
-                    if (executionexception.getCause() instanceof RuntimeException) {
-                        throw (RuntimeException) executionexception.getCause();
-                    }
+                CompletableFuture completablefuture = worldserver.getChunkProvider().a((Iterable) list, (chunk) -> {
+                    set.add(chunk.getPos());
+                });
+
+                while (!completablefuture.isDone()) {
+                    try {
+                        completablefuture.get(1L, TimeUnit.SECONDS);
+                    } catch (InterruptedException interruptedexception) {
+                        throw new RuntimeException(interruptedexception);
+                    } catch (ExecutionException executionexception) {
+                        if (executionexception.getCause() instanceof RuntimeException) {
+                            throw (RuntimeException) executionexception.getCause();
+                        }
 
-                    throw new RuntimeException(executionexception.getCause());
-                } catch (TimeoutException timeoutexception) {
-                    this.a(new ChatMessage("menu.preparingSpawn", new Object[0]), set.size() * 100 / 625);
+                        throw new RuntimeException(executionexception.getCause());
+                    } catch (TimeoutException timeoutexception) {
+                        this.a(new ChatMessage("menu.preparingSpawn", new Object[0]), set.size() * 100 / 625);
+                    }
                 }
-            }
 
-            this.a(new ChatMessage("menu.preparingSpawn", new Object[0]), set.size() * 100 / 625);
+                this.a(new ChatMessage("menu.preparingSpawn", new Object[0]), set.size() * 100 / 625);
+            }
         }
 
+        for (WorldServer world : this.getWorlds()) {
+            this.server.getPluginManager().callEvent(new org.bukkit.event.world.WorldLoadEvent(world.getWorld()));
+        }
+        // CraftBukkit end
         MinecraftServer.LOGGER.info("Time elapsed: {} ms", stopwatch.elapsed(TimeUnit.MILLISECONDS));
         Iterator iterator = DimensionManager.b().iterator();
 
@@ -414,6 +566,10 @@
     protected void l() {
         this.w = null;
         this.x = 0;
+        // CraftBukkit Start
+        this.server.enablePlugins(org.bukkit.plugin.PluginLoadOrder.POSTWORLD);
+        this.server.getPluginManager().callEvent(new ServerLoadEvent(ServerLoadEvent.LoadType.STARTUP));
+        // CraftBukkit end
     }
 
     protected void saveChunks(boolean flag) {
@@ -437,8 +593,24 @@
 
     }
 
-    protected void stop() {
+    // CraftBukkit start
+    private boolean hasStopped = false;
+    private final Object stopLock = new Object();
+    // CraftBukkit end
+
+    public void stop() throws ExceptionWorldConflict { // CraftBukkit - added throws
+        // CraftBukkit start - prevent double stopping on multiple threads
+        synchronized(stopLock) {
+            if (hasStopped) return;
+            hasStopped = true;
+        }
+        // CraftBukkit end
         MinecraftServer.LOGGER.info("Stopping server");
+        // CraftBukkit start
+        if (this.server != null) {
+            this.server.disablePlugins();
+        }
+        // CraftBukkit end
         if (this.getServerConnection() != null) {
             this.getServerConnection().b();
         }
@@ -447,6 +619,7 @@
             MinecraftServer.LOGGER.info("Saving players");
             this.playerList.savePlayers();
             this.playerList.u();
+            try { Thread.sleep(100); } catch (InterruptedException ex) {} // CraftBukkit - SPIGOT-625 - give server at least a chance to send packets
         }
 
         MinecraftServer.LOGGER.info("Saving worlds");
@@ -511,11 +684,13 @@
                     if (i > 2000L && this.nextTick - this.lastOverloadTime >= 15000L) {
                         long j = i / 50L;
 
+                        if (server.getWarnOnOverload()) // CraftBukkit
                         MinecraftServer.LOGGER.warn("Can't keep up! Is the server overloaded? Running {}ms or {} ticks behind", i, j);
                         this.nextTick += j * 50L;
                         this.lastOverloadTime = this.nextTick;
                     }
 
+                    MinecraftServer.currentTick = (int) (System.currentTimeMillis() / 50); // CraftBukkit
                     this.a(this::canSleepForTick);
                     this.nextTick += 50L;
 
@@ -554,6 +729,12 @@
             } catch (Throwable throwable1) {
                 MinecraftServer.LOGGER.error("Exception stopping the server", throwable1);
             } finally {
+                // CraftBukkit start - Restore terminal to original settings
+                try {
+                    reader.getTerminal().restore();
+                } catch (Exception ignored) {
+                }
+                // CraftBukkit end
                 this.t();
             }
 
@@ -622,7 +803,7 @@
             this.m.b().a(agameprofile);
         }
 
-        if (this.ticks % 900 == 0) {
+        if (autosavePeriod > 0 && this.ticks % autosavePeriod == 0) { // CraftBukkit
             this.methodProfiler.enter("save");
             this.playerList.savePlayers();
             this.saveChunks(true);
@@ -648,6 +829,7 @@
     }
 
     public void b(BooleanSupplier booleansupplier) {
+        this.server.getScheduler().mainThreadHeartbeat(this.ticks); // CraftBukkit
         this.methodProfiler.enter("jobs");
 
         FutureTask futuretask;
@@ -660,23 +842,40 @@
         this.getFunctionData().tick();
         this.methodProfiler.exitEnter("levels");
 
-        WorldServer worldserver;
+        // CraftBukkit start
+        // Run tasks that are waiting on processing
+        while (!processQueue.isEmpty()) {
+            processQueue.remove().run();
+        }
+
+        org.bukkit.craftbukkit.chunkio.ChunkIOExecutor.tick();
+
+        // Send time updates to everyone, it will get the right time from the world the player is in.
+        if (this.ticks % 20 == 0) {
+            for (int i = 0; i < this.getPlayerList().players.size(); ++i) {
+                EntityPlayer entityplayer = (EntityPlayer) this.getPlayerList().players.get(i);
+                entityplayer.playerConnection.sendPacket(new PacketPlayOutUpdateTime(entityplayer.world.getTime(), entityplayer.getPlayerTime(), entityplayer.world.getGameRules().getBoolean("doDaylightCycle"))); // Add support for per player time
+            }
+        }
+
+        // WorldServer worldserver; // CraftBukkit - dropped down
         long i;
 
-        for (Iterator iterator = this.getWorlds().iterator(); iterator.hasNext();((long[]) this.e.computeIfAbsent(worldserver.worldProvider.getDimensionManager(), (dimensionmanager) -> {
-            return new long[100];
-        }))[this.ticks % 100] = SystemUtils.getMonotonicNanos() - i) {
-            worldserver = (WorldServer) iterator.next();
+        // CraftBukkit - dropTickTime
+        for (Iterator iterator = this.getWorlds().iterator(); iterator.hasNext();) {
+             WorldServer worldserver = (WorldServer) iterator.next();
             i = SystemUtils.getMonotonicNanos();
-            if (worldserver.worldProvider.getDimensionManager() == DimensionManager.OVERWORLD || this.getAllowNether()) {
+            if (true || worldserver.worldProvider.getDimensionManager() == DimensionManager.OVERWORLD || this.getAllowNether()) { // CraftBukkit
                 this.methodProfiler.a(() -> {
                     return "dim-" + worldserver.worldProvider.getDimensionManager().getDimensionID();
                 });
+                /* Drop global time updates
                 if (this.ticks % 20 == 0) {
                     this.methodProfiler.enter("timeSync");
                     this.playerList.a((Packet) (new PacketPlayOutUpdateTime(worldserver.getTime(), worldserver.getDayTime(), worldserver.getGameRules().getBoolean("doDaylightCycle"))), worldserver.worldProvider.getDimensionManager());
                     this.methodProfiler.exit();
                 }
+                // CraftBukkit end */
 
                 this.methodProfiler.enter("tick");
 
@@ -727,10 +926,11 @@
         this.k.add(itickable);
     }
 
-    public static void main(String[] astring) {
+    public static void main(final OptionSet options) { // CraftBukkit - replaces main(String[] astring)
         DispenserRegistry.c();
 
         try {
+            /* CraftBukkit start - Replace everything
             boolean flag = true;
             String s = null;
             String s1 = ".";
@@ -778,13 +978,16 @@
                     ++j;
                 }
             }
+            */ // CraftBukkit end
 
+            String s1 = "."; // PAIL?
             YggdrasilAuthenticationService yggdrasilauthenticationservice = new YggdrasilAuthenticationService(Proxy.NO_PROXY, UUID.randomUUID().toString());
             MinecraftSessionService minecraftsessionservice = yggdrasilauthenticationservice.createMinecraftSessionService();
             GameProfileRepository gameprofilerepository = yggdrasilauthenticationservice.createProfileRepository();
             UserCache usercache = new UserCache(gameprofilerepository, new File(s1, MinecraftServer.a.getName()));
-            final DedicatedServer dedicatedserver = new DedicatedServer(new File(s1), DataConverterRegistry.a(), yggdrasilauthenticationservice, minecraftsessionservice, gameprofilerepository, usercache);
+            final DedicatedServer dedicatedserver = new DedicatedServer(options, DataConverterRegistry.a(), yggdrasilauthenticationservice, minecraftsessionservice, gameprofilerepository, usercache);
 
+            /* CraftBukkit start
             if (s != null) {
                 dedicatedserver.h(s);
             }
@@ -822,6 +1025,29 @@
 
             thread.setUncaughtExceptionHandler(new DefaultUncaughtExceptionHandler(MinecraftServer.LOGGER));
             Runtime.getRuntime().addShutdownHook(thread);
+            */
+
+            if (options.has("port")) {
+                int port = (Integer) options.valueOf("port");
+                if (port > 0) {
+                    dedicatedserver.setPort(port);
+                }
+            }
+
+            if (options.has("universe")) {
+                dedicatedserver.universe = (File) options.valueOf("universe");
+            }
+
+            if (options.has("world")) {
+                dedicatedserver.setWorld((String) options.valueOf("world"));
+            }
+
+            if (options.has("forceUpgrade")) {
+                dedicatedserver.setForceUpgrade(true);
+            }
+
+            dedicatedserver.primaryThread.start();
+            // CraftBukkit end
         } catch (Exception exception) {
             MinecraftServer.LOGGER.fatal("Failed to start the minecraft server", exception);
         }
@@ -833,11 +1059,13 @@
     }
 
     public void v() {
+        /* CraftBukkit start - prevent abuse
         this.serverThread = new Thread(this, "Server thread");
         this.serverThread.setUncaughtExceptionHandler((thread, throwable) -> {
             MinecraftServer.LOGGER.error(throwable);
         });
         this.serverThread.start();
+        // CraftBukkit end */
     }
 
     public File c(String s) {
@@ -877,7 +1105,7 @@
     }
 
     public boolean isDebugging() {
-        return false;
+        return this.getPropertyManager().getBoolean("debug", false); // CraftBukkit - don't hardcode
     }
 
     public void f(String s) {
@@ -892,7 +1120,7 @@
     }
 
     public String getServerModName() {
-        return "vanilla";
+        return server.getName(); // CraftBukkit - cb > vanilla!
     }
 
     public CrashReport b(CrashReport crashreport) {
@@ -928,7 +1156,7 @@
     }
 
     public boolean D() {
-        return this.universe != null;
+        return true; // CraftBukkit
     }
 
     public void sendMessage(IChatBaseComponent ichatbasecomponent) {
@@ -1068,7 +1296,7 @@
     public abstract boolean Q();
 
     public boolean getOnlineMode() {
-        return this.onlineMode;
+        return server.getOnlineMode(); // CraftBukkit
     }
 
     public void setOnlineMode(boolean flag) {
@@ -1228,7 +1456,7 @@
 
     public <V> ListenableFuture<V> a(Callable<V> callable) {
         Validate.notNull(callable);
-        if (!this.isMainThread() && !this.isStopped()) {
+        if (!this.isMainThread()) { // CraftBukkit && !this.isStopped()) {
             ListenableFutureTask<V> listenablefuturetask = ListenableFutureTask.create(callable);
 
             this.f.add(listenablefuturetask);
@@ -1411,4 +1639,11 @@
             return 0;
         }
     }
+
+    // CraftBukkit start
+    @Deprecated
+    public static MinecraftServer getServer() {
+        return (Bukkit.getServer() instanceof CraftServer) ? ((CraftServer) Bukkit.getServer()).getServer() : null;
+    }
+    // CraftBukkit end
 }