From 2f74bdb56bfe134bb84b9e11fb67885ab00346d5 Mon Sep 17 00:00:00 2001 From: Zach Brown <1254957+zachbr@users.noreply.github.com> Date: Fri, 12 May 2017 23:34:11 -0500 Subject: [PATCH] Properly handle async calls to restart the server The watchdog thread calls the server restart function asynchronously. Prior to this change, it attempted to do several non-safe operations from the watchdog thread, rather than the main. Specifically, because of a separate upstream change, it causes player entities to be ticked asynchronously, among other things. This is dangerous. This patch moves the old handling into a synchronous variant, for calls from the restart command, and adds separate handling for async calls, such as those from the watchdog thread. When calling from the watchdog thread, we cannot assume the main thread is in a tickable state; it may be completely deadlocked. In order to handle this, we mark the server as stopping, in order to account for situations where the server should complete a tick reasonbly soon, i.e. 99% of cases. Should the server not enter a state where it is stopping within 10 seconds, We will assume that the server has in fact deadlocked and will proceed to force kill the server. This modification does not force restart the server should we actually enter a deadlocked state where the server is stopping, whereas this will in most cases exit within a reasonable amount of time, to put a fixed limit on a process that will have plugins and worlds saving to the disk has a high potential to result in corruption/dataloss. --- .../server/MinecraftServer.java.patch | 133 +++++++----- .../server/players/PlayerList.java.patch | 38 ++-- .../java/org/spigotmc/RestartCommand.java | 192 +++++++++++------- 3 files changed, 219 insertions(+), 144 deletions(-) diff --git a/paper-server/patches/sources/net/minecraft/server/MinecraftServer.java.patch b/paper-server/patches/sources/net/minecraft/server/MinecraftServer.java.patch index f060f380be..ba869e11d8 100644 --- a/paper-server/patches/sources/net/minecraft/server/MinecraftServer.java.patch +++ b/paper-server/patches/sources/net/minecraft/server/MinecraftServer.java.patch @@ -114,7 +114,15 @@ private static final int OVERLOADED_TICKS_THRESHOLD = 20; private static final long OVERLOADED_WARNING_INTERVAL_NANOS = 10L * TimeUtil.NANOSECONDS_PER_SECOND; private static final int OVERLOADED_TICKS_WARNING_INTERVAL = 100; -@@ -232,8 +255,7 @@ +@@ -224,6 +247,7 @@ + private Map, ServerLevel> levels; + private PlayerList playerList; + private volatile boolean running; ++ private volatile boolean isRestarting = false; // Paper - flag to signify we're attempting to restart + private boolean stopped; + private int tickCount; + private int ticksUntilAutosave; +@@ -232,8 +256,7 @@ private boolean preventProxyConnections; private boolean pvp; private boolean allowFlight; @@ -124,7 +132,7 @@ private int playerIdleTimeout; private final long[] tickTimesNanos; private long aggregatedTickTimesNanos; -@@ -277,6 +299,26 @@ +@@ -277,6 +300,26 @@ private final SuppressedExceptionCollector suppressedExceptions; private final DiscontinuousFrame tickFrame; @@ -151,7 +159,7 @@ public static S spin(Function serverFactory) { AtomicReference atomicreference = new AtomicReference(); Thread thread = new Thread(() -> { -@@ -290,15 +332,16 @@ +@@ -290,15 +333,16 @@ thread.setPriority(8); } @@ -170,7 +178,7 @@ this.metricsRecorder = InactiveMetricsRecorder.INSTANCE; this.onMetricsRecordingStopped = (methodprofilerresults) -> { this.stopRecordingMetrics(); -@@ -319,36 +362,68 @@ +@@ -319,36 +363,68 @@ this.scoreboard = new ServerScoreboard(this); this.customBossEvents = new CustomBossEvents(); this.suppressedExceptions = new SuppressedExceptionCollector(); @@ -254,7 +262,7 @@ } private void readScoreboard(DimensionDataStorage persistentStateManager) { -@@ -357,7 +432,7 @@ +@@ -357,7 +433,7 @@ protected abstract boolean initServer() throws IOException; @@ -263,7 +271,7 @@ if (!JvmProfiler.INSTANCE.isRunning()) { ; } -@@ -365,12 +440,8 @@ +@@ -365,12 +441,8 @@ boolean flag = false; ProfiledDuration profiledduration = JvmProfiler.INSTANCE.onWorldLoadedStarted(); @@ -277,7 +285,7 @@ if (profiledduration != null) { profiledduration.finish(true); } -@@ -387,23 +458,232 @@ +@@ -387,23 +459,232 @@ protected void forceDifficulty() {} @@ -524,7 +532,7 @@ if (!iworlddataserver.isInitialized()) { try { -@@ -427,30 +707,8 @@ +@@ -427,30 +708,8 @@ iworlddataserver.setInitialized(true); } @@ -556,7 +564,7 @@ private static void setInitialSpawn(ServerLevel world, ServerLevelData worldProperties, boolean bonusChest, boolean debugWorld) { if (debugWorld) { -@@ -458,6 +716,21 @@ +@@ -458,6 +717,21 @@ } else { ServerChunkCache chunkproviderserver = world.getChunkSource(); ChunkPos chunkcoordintpair = new ChunkPos(chunkproviderserver.randomState().sampler().findSpawnPosition()); @@ -578,7 +586,7 @@ int i = chunkproviderserver.getGenerator().getSpawnHeight(world); if (i < world.getMinY()) { -@@ -516,31 +789,36 @@ +@@ -516,31 +790,36 @@ iworlddataserver.setGameType(GameType.SPECTATOR); } @@ -626,7 +634,7 @@ ForcedChunksSavedData forcedchunk = (ForcedChunksSavedData) worldserver1.getDataStorage().get(ForcedChunksSavedData.factory(), "chunks"); if (forcedchunk != null) { -@@ -555,10 +833,17 @@ +@@ -555,10 +834,17 @@ } } @@ -648,7 +656,7 @@ } public GameType getDefaultGameType() { -@@ -588,12 +873,16 @@ +@@ -588,12 +874,16 @@ worldserver.save((ProgressListener) null, flush, worldserver.noSave && !force); } @@ -667,7 +675,7 @@ if (flush) { Iterator iterator1 = this.getAllLevels().iterator(); -@@ -628,18 +917,41 @@ +@@ -628,18 +918,41 @@ this.stopServer(); } @@ -704,12 +712,13 @@ if (this.playerList != null) { MinecraftServer.LOGGER.info("Saving players"); this.playerList.saveAll(); - this.playerList.removeAll(); +- this.playerList.removeAll(); ++ this.playerList.removeAll(this.isRestarting); // Paper + try { Thread.sleep(100); } catch (InterruptedException ex) {} // CraftBukkit - SPIGOT-625 - give server at least a chance to send packets } MinecraftServer.LOGGER.info("Saving worlds"); -@@ -693,6 +1005,15 @@ +@@ -693,6 +1006,15 @@ } catch (IOException ioexception1) { MinecraftServer.LOGGER.error("Failed to unlock level {}", this.storageSource.getLevelId(), ioexception1); } @@ -725,7 +734,19 @@ } -@@ -715,10 +1036,68 @@ +@@ -709,16 +1031,80 @@ + } + + public void halt(boolean waitForShutdown) { ++ // Paper start - allow passing of the intent to restart ++ this.safeShutdown(waitForShutdown, false); ++ } ++ public void safeShutdown(boolean waitForShutdown, boolean isRestarting) { ++ this.isRestarting = isRestarting; ++ // Paper end + this.running = false; + if (waitForShutdown) { + try { this.serverThread.join(); } catch (InterruptedException interruptedexception) { MinecraftServer.LOGGER.error("Error while shutting down", interruptedexception); @@ -794,7 +815,7 @@ protected void runServer() { try { -@@ -727,9 +1106,15 @@ +@@ -727,9 +1113,15 @@ } this.nextTickTimeNanos = Util.getNanos(); @@ -811,7 +832,7 @@ while (this.running) { long i; -@@ -744,11 +1129,30 @@ +@@ -744,12 +1136,31 @@ if (j > MinecraftServer.OVERLOADED_THRESHOLD_NANOS + 20L * i && this.nextTickTimeNanos - this.lastOverloadWarningNanos >= MinecraftServer.OVERLOADED_WARNING_INTERVAL_NANOS + 100L * i) { long k = j / i; @@ -820,7 +841,7 @@ this.nextTickTimeNanos += k * i; this.lastOverloadWarningNanos = this.nextTickTimeNanos; } -+ } + } + // Spigot start + // Paper start - further improve server tick loop + currentTime = Util.getNanos(); @@ -830,19 +851,20 @@ + tps1.add(currentTps, diff); + tps5.add(currentTps, diff); + tps15.add(currentTps, diff); -+ + + // Backwards compat with bad plugins + this.recentTps[0] = tps1.getAverage(); + this.recentTps[1] = tps5.getAverage(); + this.recentTps[2] = tps15.getAverage(); + tickSection = currentTime; - } ++ } + // Paper end - further improve server tick loop + // Spigot end - ++ boolean flag = i == 0L; -@@ -757,6 +1161,8 @@ + if (this.debugCommandProfilerDelayStart) { +@@ -757,6 +1168,8 @@ this.debugCommandProfiler = new MinecraftServer.TimeProfiler(Util.getNanos(), this.tickCount); } @@ -851,7 +873,7 @@ this.nextTickTimeNanos += i; try { -@@ -830,6 +1236,13 @@ +@@ -830,6 +1243,13 @@ this.services.profileCache().clearExecutor(); } @@ -865,23 +887,25 @@ this.onServerExit(); } -@@ -889,7 +1302,14 @@ +@@ -889,9 +1309,16 @@ } private boolean haveTime() { - return this.runningTask() || Util.getNanos() < (this.mayHaveDelayedTasks ? this.delayedTasksMaxNextTickTimeNanos : this.nextTickTimeNanos); + // CraftBukkit start + return this.forceTicks || this.runningTask() || Util.getNanos() < (this.mayHaveDelayedTasks ? this.delayedTasksMaxNextTickTimeNanos : this.nextTickTimeNanos); -+ } -+ + } + + private void executeModerately() { + this.runAllTasks(); + java.util.concurrent.locks.LockSupport.parkNanos("executing tasks", 1000L); + // CraftBukkit end - } - ++ } ++ public static boolean throwIfFatalException() { -@@ -903,7 +1323,7 @@ + RuntimeException runtimeexception = (RuntimeException) MinecraftServer.fatalException.get(); + +@@ -903,7 +1330,7 @@ } public static void setFatalException(RuntimeException exception) { @@ -890,7 +914,7 @@ } @Override -@@ -977,7 +1397,7 @@ +@@ -977,7 +1404,7 @@ } } @@ -899,7 +923,7 @@ Profiler.get().incrementCounter("runTask"); super.doRunTask(ticktask); } -@@ -1025,6 +1445,7 @@ +@@ -1025,6 +1452,7 @@ } public void tickServer(BooleanSupplier shouldKeepTicking) { @@ -907,7 +931,7 @@ long i = Util.getNanos(); int j = this.pauseWhileEmptySeconds() * 20; -@@ -1041,6 +1462,7 @@ +@@ -1041,6 +1469,7 @@ this.autoSave(); } @@ -915,7 +939,7 @@ this.tickConnection(); return; } -@@ -1055,12 +1477,13 @@ +@@ -1055,12 +1484,13 @@ } --this.ticksUntilAutosave; @@ -930,7 +954,7 @@ gameprofilerfiller.push("tallying"); long k = Util.getNanos() - i; int l = this.tickCount % 100; -@@ -1074,7 +1497,7 @@ +@@ -1074,7 +1504,7 @@ } private void autoSave() { @@ -939,7 +963,7 @@ MinecraftServer.LOGGER.debug("Autosave started"); ProfilerFiller gameprofilerfiller = Profiler.get(); -@@ -1123,7 +1546,7 @@ +@@ -1123,7 +1553,7 @@ private ServerStatus buildServerStatus() { ServerStatus.Players serverping_serverpingplayersample = this.buildPlayerStatus(); @@ -948,7 +972,7 @@ } private ServerStatus.Players buildPlayerStatus() { -@@ -1154,24 +1577,43 @@ +@@ -1154,24 +1584,43 @@ this.getPlayerList().getPlayers().forEach((entityplayer) -> { entityplayer.connection.suspendFlushing(); }); @@ -992,7 +1016,7 @@ gameprofilerfiller.push("tick"); -@@ -1186,6 +1628,7 @@ +@@ -1186,6 +1635,7 @@ gameprofilerfiller.pop(); gameprofilerfiller.pop(); @@ -1000,12 +1024,10 @@ } gameprofilerfiller.popPush("connection"); -@@ -1265,7 +1708,23 @@ - @Nullable - public ServerLevel getLevel(ResourceKey key) { +@@ -1267,6 +1717,22 @@ return (ServerLevel) this.levels.get(key); -+ } -+ + } + + // CraftBukkit start + public void addLevel(ServerLevel level) { + Map, ServerLevel> oldLevels = this.levels; @@ -1019,12 +1041,13 @@ + Map, ServerLevel> newLevels = Maps.newLinkedHashMap(oldLevels); + newLevels.remove(level.dimension()); + this.levels = Collections.unmodifiableMap(newLevels); - } ++ } + // CraftBukkit end - ++ public Set> levelKeys() { return this.levels.keySet(); -@@ -1296,7 +1755,7 @@ + } +@@ -1296,7 +1762,7 @@ @DontObfuscate public String getServerModName() { @@ -1033,7 +1056,7 @@ } public SystemReport fillSystemReport(SystemReport details) { -@@ -1347,7 +1806,7 @@ +@@ -1347,7 +1813,7 @@ @Override public void sendSystemMessage(Component message) { @@ -1042,7 +1065,7 @@ } public KeyPair getKeyPair() { -@@ -1481,10 +1940,20 @@ +@@ -1481,10 +1947,20 @@ @Override public String getMotd() { @@ -1064,7 +1087,7 @@ this.motd = motd; } -@@ -1507,7 +1976,7 @@ +@@ -1507,7 +1983,7 @@ } public ServerConnectionListener getConnection() { @@ -1073,7 +1096,7 @@ } public boolean isReady() { -@@ -1634,11 +2103,11 @@ +@@ -1634,11 +2110,11 @@ public CompletableFuture reloadResources(Collection dataPacks) { CompletableFuture completablefuture = CompletableFuture.supplyAsync(() -> { @@ -1087,7 +1110,7 @@ }, this).thenCompose((immutablelist) -> { MultiPackResourceManager resourcemanager = new MultiPackResourceManager(PackType.SERVER_DATA, immutablelist); List> list = TagLoader.loadTagsForExistingRegistries(resourcemanager, this.registries.compositeAccess()); -@@ -1654,6 +2123,7 @@ +@@ -1654,6 +2130,7 @@ }).thenAcceptAsync((minecraftserver_reloadableresources) -> { this.resources.close(); this.resources = minecraftserver_reloadableresources; @@ -1095,7 +1118,7 @@ this.packRepository.setSelected(dataPacks); WorldDataConfiguration worlddataconfiguration = new WorldDataConfiguration(MinecraftServer.getSelectedPacks(this.packRepository, true), this.worldData.enabledFeatures()); -@@ -1952,7 +2422,7 @@ +@@ -1952,7 +2429,7 @@ final List list = Lists.newArrayList(); final GameRules gamerules = this.getGameRules(); @@ -1104,7 +1127,7 @@ @Override public > void visit(GameRules.Key key, GameRules.Type type) { list.add(String.format(Locale.ROOT, "%s=%s\n", key.getId(), gamerules.getRule(key))); -@@ -2058,7 +2528,7 @@ +@@ -2058,7 +2535,7 @@ try { label51: { @@ -1113,7 +1136,7 @@ try { arraylist = Lists.newArrayList(NativeModuleLister.listModules()); -@@ -2105,8 +2575,23 @@ +@@ -2105,8 +2582,23 @@ if (bufferedwriter != null) { bufferedwriter.close(); } @@ -1137,7 +1160,7 @@ private ProfilerFiller createProfiler() { if (this.willStartRecordingMetrics) { -@@ -2225,18 +2710,24 @@ +@@ -2225,18 +2717,24 @@ } public void logChatMessage(Component message, ChatType.Bound params, @Nullable String prefix) { diff --git a/paper-server/patches/sources/net/minecraft/server/players/PlayerList.java.patch b/paper-server/patches/sources/net/minecraft/server/players/PlayerList.java.patch index 0003450eff..ae79998941 100644 --- a/paper-server/patches/sources/net/minecraft/server/players/PlayerList.java.patch +++ b/paper-server/patches/sources/net/minecraft/server/players/PlayerList.java.patch @@ -729,14 +729,10 @@ this.sendAllPlayerInfoIn = 0; } -@@ -537,9 +832,28 @@ - ServerPlayer entityplayer = (ServerPlayer) iterator.next(); +@@ -541,6 +836,25 @@ + + } - entityplayer.connection.send(packet); -+ } -+ -+ } -+ + // CraftBukkit start - add a world/entity limited version + public void broadcastAll(Packet packet, net.minecraft.world.entity.player.Player entityhuman) { + for (int i = 0; i < this.players.size(); ++i) { @@ -751,13 +747,14 @@ + public void broadcastAll(Packet packet, Level world) { + for (int i = 0; i < world.players().size(); ++i) { + ((ServerPlayer) world.players().get(i)).connection.send(packet); - } - - } ++ } ++ ++ } + // CraftBukkit end - ++ public void broadcastAll(Packet packet, ResourceKey dimension) { Iterator iterator = this.players.iterator(); + @@ -554,7 +868,7 @@ } @@ -880,14 +877,21 @@ } public int getPlayerCount() { -@@ -786,12 +1111,29 @@ +@@ -786,12 +1111,36 @@ } public void removeAll() { - for (int i = 0; i < this.players.size(); ++i) { - ((ServerPlayer) this.players.get(i)).connection.disconnect((Component) Component.translatable("multiplayer.disconnect.server_shutdown")); ++ // Paper start - Extract method to allow for restarting flag ++ this.removeAll(false); ++ } ++ ++ public void removeAll(boolean isRestarting) { ++ // Paper end + // CraftBukkit start - disconnect safely + for (ServerPlayer player : this.players) { ++ if (isRestarting) player.connection.disconnect(net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer.legacySection().deserialize(org.spigotmc.SpigotConfig.restartMessage)); else // Paper + player.connection.disconnect(java.util.Objects.requireNonNullElseGet(this.server.server.shutdownMessage(), net.kyori.adventure.text.Component::empty)); // CraftBukkit - add custom shutdown message // Paper - Adventure } + // CraftBukkit end @@ -912,7 +916,7 @@ public void broadcastSystemMessage(Component message, boolean overlay) { this.broadcastSystemMessage(message, (entityplayer) -> { return message; -@@ -819,24 +1161,43 @@ +@@ -819,24 +1168,43 @@ } public void broadcastChatMessage(PlayerChatMessage message, ServerPlayer sender, ChatType.Bound params) { @@ -959,7 +963,7 @@ } if (flag1 && sender != null) { -@@ -845,20 +1206,27 @@ +@@ -845,20 +1213,27 @@ } @@ -992,7 +996,7 @@ Path path = file2.toPath(); if (FileUtil.isPathNormalized(path) && FileUtil.isPathPortable(path) && path.startsWith(file.getPath()) && file2.isFile()) { -@@ -867,7 +1235,7 @@ +@@ -867,7 +1242,7 @@ } serverstatisticmanager = new ServerStatsCounter(this.server, file1); @@ -1001,7 +1005,7 @@ } return serverstatisticmanager; -@@ -875,13 +1243,13 @@ +@@ -875,13 +1250,13 @@ public PlayerAdvancements getPlayerAdvancements(ServerPlayer player) { UUID uuid = player.getUUID(); @@ -1017,7 +1021,7 @@ } advancementdataplayer.setPlayer(player); -@@ -932,15 +1300,28 @@ +@@ -932,15 +1307,28 @@ } public void reloadResources() { diff --git a/paper-server/src/main/java/org/spigotmc/RestartCommand.java b/paper-server/src/main/java/org/spigotmc/RestartCommand.java index de8c703803..824c4ad135 100644 --- a/paper-server/src/main/java/org/spigotmc/RestartCommand.java +++ b/paper-server/src/main/java/org/spigotmc/RestartCommand.java @@ -46,86 +46,134 @@ public class RestartCommand extends Command AsyncCatcher.enabled = false; // Disable async catcher incase it interferes with us try { - String[] split = restartScript.split( " " ); - if ( split.length > 0 && new File( split[0] ).isFile() ) + // Paper - extract method and cleanup + boolean isRestarting = addShutdownHook( restartScript ); + if ( isRestarting ) { - System.out.println( "Attempting to restart with " + restartScript ); - - // Disable Watchdog - WatchdogThread.doStop(); - - // Kick all players - for ( ServerPlayer p : (List) MinecraftServer.getServer().getPlayerList().players ) - { - p.connection.disconnect( CraftChatMessage.fromStringOrEmpty( SpigotConfig.restartMessage, true ) ); - } - // Give the socket a chance to send the packets - try - { - Thread.sleep( 100 ); - } catch ( InterruptedException ex ) - { - } - // Close the socket so we can rebind with the new process - MinecraftServer.getServer().getConnection().stop(); - - // Give time for it to kick in - try - { - Thread.sleep( 100 ); - } catch ( InterruptedException ex ) - { - } - - // Actually shutdown - try - { - MinecraftServer.getServer().close(); - } catch ( Throwable t ) - { - } - - // This will be done AFTER the server has completely halted - Thread shutdownHook = new Thread() - { - @Override - public void run() - { - try - { - String os = System.getProperty( "os.name" ).toLowerCase(java.util.Locale.ENGLISH); - if ( os.contains( "win" ) ) - { - Runtime.getRuntime().exec( "cmd /c start " + restartScript ); - } else - { - Runtime.getRuntime().exec( "sh " + restartScript ); - } - } catch ( Exception e ) - { - e.printStackTrace(); - } - } - }; - - shutdownHook.setDaemon( true ); - Runtime.getRuntime().addShutdownHook( shutdownHook ); + System.out.println( "Attempting to restart with " + SpigotConfig.restartScript ); } else { System.out.println( "Startup script '" + SpigotConfig.restartScript + "' does not exist! Stopping server." ); - - // Actually shutdown - try - { - MinecraftServer.getServer().close(); - } catch ( Throwable t ) - { - } } - System.exit( 0 ); + // Stop the watchdog + WatchdogThread.doStop(); + + shutdownServer( isRestarting ); + // Paper end } catch ( Exception ex ) { ex.printStackTrace(); } } + + // Paper start - sync copied from above with minor changes, async added + private static void shutdownServer(boolean isRestarting) + { + if ( MinecraftServer.getServer().isSameThread() ) + { + // Kick all players + for ( ServerPlayer p : com.google.common.collect.ImmutableList.copyOf( MinecraftServer.getServer().getPlayerList().players ) ) + { + p.connection.disconnect( CraftChatMessage.fromStringOrEmpty( SpigotConfig.restartMessage, true ) ); + } + // Give the socket a chance to send the packets + try + { + Thread.sleep( 100 ); + } catch ( InterruptedException ex ) + { + } + + closeSocket(); + + // Actually shutdown + try + { + MinecraftServer.getServer().close(); // calls stop() + } catch ( Throwable t ) + { + } + + // Actually stop the JVM + System.exit( 0 ); + + } else + { + // Mark the server to shutdown at the end of the tick + MinecraftServer.getServer().safeShutdown( false, isRestarting ); + + // wait 10 seconds to see if we're actually going to try shutdown + try + { + Thread.sleep( 10000 ); + } + catch (InterruptedException ignored) + { + } + + // Check if we've actually hit a state where the server is going to safely shutdown + // if we have, let the server stop as usual + if (MinecraftServer.getServer().isStopped()) return; + + // If the server hasn't stopped by now, assume worse case and kill + closeSocket(); + System.exit( 0 ); + } + } + // Paper end + + // Paper - Split from moved code + private static void closeSocket() + { + // Close the socket so we can rebind with the new process + MinecraftServer.getServer().getConnection().stop(); + + // Give time for it to kick in + try + { + Thread.sleep( 100 ); + } catch ( InterruptedException ex ) + { + } + } + // Paper end + + // Paper start - copied from above and modified to return if the hook registered + private static boolean addShutdownHook(String restartScript) + { + String[] split = restartScript.split( " " ); + if ( split.length > 0 && new File( split[0] ).isFile() ) + { + Thread shutdownHook = new Thread() + { + @Override + public void run() + { + try + { + String os = System.getProperty( "os.name" ).toLowerCase(java.util.Locale.ENGLISH); + if ( os.contains( "win" ) ) + { + Runtime.getRuntime().exec( "cmd /c start " + restartScript ); + } else + { + Runtime.getRuntime().exec( "sh " + restartScript ); + } + } catch ( Exception e ) + { + e.printStackTrace(); + } + } + }; + + shutdownHook.setDaemon( true ); + Runtime.getRuntime().addShutdownHook( shutdownHook ); + return true; + } else + { + return false; + } + } + // Paper end + }