Add basis of grouped thread factory and make the scheduler use it.

api/src/main/java/net/md_5/bungee/api/plugin/Plugin.java

@@ -1,11 +1,16 @@
 package net.md_5.bungee.api.plugin;
 
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import java.io.File;
 import java.io.InputStream;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadFactory;
 import java.util.logging.Logger;
 import lombok.Getter;
 import net.md_5.bungee.api.ProxyServer;
 import net.md_5.bungee.api.config.ConfigurationAdapter;
+import net.md_5.bungee.api.scheduler.GroupedThreadFactory;
 
 /**
  * Represents any Plugin that may be loaded at runtime to enhance existing
@@ -83,4 +88,19 @@ public class Plugin
         this.file = description.getFile();
         this.logger = new PluginLogger( this );
     }
+
+    //
+    private ExecutorService service;
+
+    @Deprecated
+    public ExecutorService getExecutorService()
+    {
+        if ( service == null )
+        {
+            service = Executors.newCachedThreadPool( new ThreadFactoryBuilder().setNameFormat( getDescription().getName() + " Pool Thread #%1$d" )
+                    .setThreadFactory( new GroupedThreadFactory( this ) ).build() );
+        }
+        return service;
+    }
+    //
 }

api/src/main/java/net/md_5/bungee/api/scheduler/GroupedThreadFactory.java

@@ -0,0 +1,34 @@
+package net.md_5.bungee.api.scheduler;
+
+import java.util.concurrent.ThreadFactory;
+import lombok.Data;
+import net.md_5.bungee.api.plugin.Plugin;
+
+@Data
+@Deprecated
+public class GroupedThreadFactory implements ThreadFactory
+{
+
+    private final ThreadGroup group;
+
+    public class BungeeGroup extends ThreadGroup
+    {
+
+        private BungeeGroup(String name)
+        {
+            super( name );
+        }
+
+    }
+
+    public GroupedThreadFactory(Plugin plugin)
+    {
+        this.group = new BungeeGroup( plugin.getDescription().getName() );
+    }
+
+    @Override
+    public Thread newThread(Runnable r)
+    {
+        return new Thread( group, r );
+    }
+}

proxy/src/main/java/net/md_5/bungee/BungeeCord.java

@@ -366,9 +366,9 @@ public class BungeeCord extends ProxyServer
                         t.printStackTrace();
                     }
                     getScheduler().cancel( plugin );
+                    plugin.getExecutorService().shutdownNow();
                 }
 
-                scheduler.shutdown();
                 getLogger().info( "Thank you and goodbye" );
                 // Need to close loggers after last message!
                 for ( Handler handler : getLogger().getHandlers() )

proxy/src/main/java/net/md_5/bungee/BungeeSecurityManager.java

@@ -4,6 +4,7 @@ import java.security.AccessControlException;
 import java.security.Permission;
 import java.util.logging.Level;
 import net.md_5.bungee.api.ProxyServer;
+import net.md_5.bungee.api.scheduler.GroupedThreadFactory;
 
 public class BungeeSecurityManager extends SecurityManager
 {
@@ -54,10 +55,12 @@ public class BungeeSecurityManager extends SecurityManager
     }
 
     @Override
-    public ThreadGroup getThreadGroup()
+    public void checkAccess(ThreadGroup g)
     {
-        checkRestricted( "Thread Creation: Use scheduler" );
+        if ( !( g instanceof GroupedThreadFactory.BungeeGroup ) )
-        return super.getThreadGroup();
+        {
+            checkRestricted( "Illegal thread group access" );
+        }
     }
 
     @Override

proxy/src/main/java/net/md_5/bungee/scheduler/BungeeScheduler.java

@@ -4,14 +4,12 @@ import com.google.common.base.Preconditions;
 import com.google.common.collect.HashMultimap;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.Multimaps;
-import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import gnu.trove.TCollections;
 import gnu.trove.map.TIntObjectMap;
 import gnu.trove.map.hash.TIntObjectHashMap;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 import net.md_5.bungee.api.plugin.Plugin;
@@ -21,7 +19,6 @@ import net.md_5.bungee.api.scheduler.TaskScheduler;
 public class BungeeScheduler implements TaskScheduler
 {
 
-    private final ExecutorService s = Executors.newCachedThreadPool( new ThreadFactoryBuilder().setNameFormat( "Bungee Pool Thread #%1$d" ).build() );
     private final AtomicInteger taskCounter = new AtomicInteger();
     private final TIntObjectMap<BungeeTask> tasks = TCollections.synchronizedMap( new TIntObjectHashMap<BungeeTask>() );
     private final Multimap<Plugin, BungeeTask> tasksByPlugin = Multimaps.synchronizedMultimap( HashMultimap.<Plugin, BungeeTask>create() );
@@ -32,15 +29,10 @@ public class BungeeScheduler implements TaskScheduler
         @Override
         public ExecutorService getExecutorService(Plugin plugin)
         {
-            return s;
+            return plugin.getExecutorService();
         }
     };
 
-    public void shutdown()
-    {
-        s.shutdown();
-    }
-
     @Override
     public void cancel(int id)
     {
@@ -89,7 +81,7 @@ public class BungeeScheduler implements TaskScheduler
         Preconditions.checkNotNull( task, "task" );
         BungeeTask prepared = new BungeeTask( this, taskCounter.getAndIncrement(), owner, task, delay, period, unit );
         tasks.put( prepared.getId(), prepared );
-        s.execute( prepared );
+        owner.getExecutorService().execute( prepared );
         return prepared;
     }