Rewrite session code and add support for persistent sessions.

src/forge/java/com/sk89q/worldedit/forge/ForgePlayer.java

@@ -27,6 +27,7 @@ import com.sk89q.worldedit.extension.platform.AbstractPlayerActor;
 import com.sk89q.worldedit.extent.inventory.BlockBag;
 import com.sk89q.worldedit.internal.LocalWorldAdapter;
 import com.sk89q.worldedit.internal.cui.CUIEvent;
+import com.sk89q.worldedit.session.SessionKey;
 import com.sk89q.worldedit.util.Location;
 import net.minecraft.entity.player.EntityPlayerMP;
 import net.minecraft.item.ItemStack;
@@ -34,6 +35,7 @@ import net.minecraft.network.packet.Packet250CustomPayload;
 import net.minecraft.util.ChatMessageComponent;
 
 import javax.annotation.Nullable;
+import java.util.UUID;
 
 public class ForgePlayer extends AbstractPlayerActor {
 
@@ -41,13 +43,21 @@ public class ForgePlayer extends AbstractPlayerActor {
 
     protected ForgePlayer(EntityPlayerMP player) {
         this.player = player;
+        ThreadSafeCache.getInstance().getOnlineIds().add(getUniqueId());
     }
 
+    @Override
+    public UUID getUniqueId() {
+        return player.getUniqueID();
+    }
+
+    @Override
     public int getItemInHand() {
         ItemStack is = this.player.getCurrentEquippedItem();
         return is == null ? 0 : is.itemID;
     }
 
+    @Override
     public String getName() {
         return this.player.username;
     }
@@ -67,26 +77,32 @@ public class ForgePlayer extends AbstractPlayerActor {
                 this.player.cameraPitch);
     }
 
+    @Override
     public WorldVector getPosition() {
         return new WorldVector(LocalWorldAdapter.adapt(ForgeWorldEdit.inst.getWorld(this.player.worldObj)), this.player.posX, this.player.posY, this.player.posZ);
     }
 
+    @Override
     public com.sk89q.worldedit.world.World getWorld() {
         return ForgeWorldEdit.inst.getWorld(this.player.worldObj);
     }
 
+    @Override
     public double getPitch() {
         return this.player.rotationPitch;
     }
 
+    @Override
     public double getYaw() {
         return this.player.rotationYaw;
     }
 
+    @Override
     public void giveItem(int type, int amt) {
         this.player.inventory.addItemStackToInventory(new ItemStack(type, amt, 0));
     }
 
+    @Override
     public void dispatchCUIEvent(CUIEvent event) {
         String[] params = event.getParameters();
         String send = event.getTypeId();
@@ -97,42 +113,50 @@ public class ForgePlayer extends AbstractPlayerActor {
         this.player.playerNetServerHandler.sendPacketToPlayer(packet);
     }
 
+    @Override
     public void printRaw(String msg) {
         for (String part : msg.split("\n")) {
             this.player.sendChatToPlayer(ChatMessageComponent.createFromText(part));
         }
     }
 
+    @Override
     public void printDebug(String msg) {
         for (String part : msg.split("\n")) {
             this.player.sendChatToPlayer(ChatMessageComponent.createFromText("\u00a77" + part));
         }
     }
 
+    @Override
     public void print(String msg) {
         for (String part : msg.split("\n")) {
             this.player.sendChatToPlayer(ChatMessageComponent.createFromText("\u00a7d" + part));
         }
     }
 
+    @Override
     public void printError(String msg) {
         for (String part : msg.split("\n")) {
             this.player.sendChatToPlayer(ChatMessageComponent.createFromText("\u00a7c" + part));
         }
     }
 
+    @Override
     public void setPosition(Vector pos, float pitch, float yaw) {
         this.player.playerNetServerHandler.setPlayerLocation(pos.getX(), pos.getY(), pos.getZ(), pitch, yaw);
     }
 
+    @Override
     public String[] getGroups() {
         return new String[]{}; // WorldEditMod.inst.getPermissionsResolver().getGroups(this.player.username);
     }
 
+    @Override
     public BlockBag getInventoryBlockBag() {
         return null;
     }
 
+    @Override
     public boolean hasPermission(String perm) {
         return ForgeUtil.hasPermission(this.player, perm);
     }
@@ -143,4 +167,45 @@ public class ForgePlayer extends AbstractPlayerActor {
         return null;
     }
 
+    @Override
+    public SessionKey getSessionKey() {
+        return new SessionKeyImpl(player.getUniqueID(), player.username);
+    }
+
+    private static class SessionKeyImpl implements SessionKey {
+        // If not static, this will leak a reference
+
+        private final UUID uuid;
+        private final String name;
+
+        private SessionKeyImpl(UUID uuid, String name) {
+            this.uuid = uuid;
+            this.name = name;
+        }
+
+        @Override
+        public UUID getUniqueId() {
+            return uuid;
+        }
+
+        @Nullable
+        @Override
+        public String getName() {
+            return name;
+        }
+
+        @Override
+        public boolean isActive() {
+            // We can't directly check if the player is online because
+            // the list of players is not thread safe
+            return ThreadSafeCache.getInstance().getOnlineIds().contains(uuid);
+        }
+
+        @Override
+        public boolean isPersistent() {
+            return true;
+        }
+
+    }
+
 }

src/forge/java/com/sk89q/worldedit/forge/ForgeWorldEdit.java

@@ -32,8 +32,15 @@ import cpw.mods.fml.common.FMLLog;
 import cpw.mods.fml.common.Mod;
 import cpw.mods.fml.common.Mod.EventHandler;
 import cpw.mods.fml.common.Mod.Instance;
-import cpw.mods.fml.common.event.*;
+import cpw.mods.fml.common.event.FMLInitializationEvent;
+import cpw.mods.fml.common.event.FMLPostInitializationEvent;
+import cpw.mods.fml.common.event.FMLPreInitializationEvent;
+import cpw.mods.fml.common.event.FMLServerAboutToStartEvent;
+import cpw.mods.fml.common.event.FMLServerStartedEvent;
+import cpw.mods.fml.common.event.FMLServerStoppingEvent;
 import cpw.mods.fml.common.network.NetworkMod;
+import cpw.mods.fml.common.registry.TickRegistry;
+import cpw.mods.fml.relauncher.Side;
 import net.minecraft.entity.player.EntityPlayerMP;
 import net.minecraft.world.World;
 import net.minecraftforge.common.MinecraftForge;
@@ -84,6 +91,8 @@ public class ForgeWorldEdit {
 
         config = new ForgeConfiguration(this);
         config.load();
+
+        TickRegistry.registerTickHandler(ThreadSafeCache.getInstance(), Side.SERVER);
     }
 
     @EventHandler

src/forge/java/com/sk89q/worldedit/forge/ThreadSafeCache.java

@@ -0,0 +1,91 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.forge;
+
+import cpw.mods.fml.common.FMLCommonHandler;
+import cpw.mods.fml.common.ITickHandler;
+import cpw.mods.fml.common.TickType;
+import net.minecraft.entity.player.EntityPlayerMP;
+
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.CopyOnWriteArraySet;
+
+/**
+ * Caches data that cannot be accessed from another thread safely.
+ */
+class ThreadSafeCache implements ITickHandler {
+
+    private static final long REFRESH_DELAY = 1000 * 30;
+    private static final ThreadSafeCache INSTANCE = new ThreadSafeCache();
+    private Set<UUID> onlineIds = Collections.emptySet();
+    private long lastRefresh = 0;
+
+    /**
+     * Get an concurrent-safe set of UUIDs of online players.
+     *
+     * @return a set of UUIDs
+     */
+    public Set<UUID> getOnlineIds() {
+        return onlineIds;
+    }
+
+    @Override
+    public void tickStart(EnumSet<TickType> type, Object... tickData) {
+        long now = System.currentTimeMillis();
+
+        if (now - lastRefresh > REFRESH_DELAY) {
+            Set<UUID> onlineIds = new HashSet<UUID>();
+
+            for (Object object : FMLCommonHandler.instance().getMinecraftServerInstance().getConfigurationManager().playerEntityList) {
+                if (object != null) {
+                    EntityPlayerMP player = (EntityPlayerMP) object;
+                    onlineIds.add(player.getUniqueID());
+                }
+            }
+
+            this.onlineIds = new CopyOnWriteArraySet<UUID>(onlineIds);
+
+            lastRefresh = now;
+        }
+    }
+
+    @Override
+    public void tickEnd(EnumSet<TickType> type, Object... tickData) {
+    }
+
+    @Override
+    public EnumSet<TickType> ticks() {
+        return EnumSet.of(TickType.SERVER);
+    }
+
+    @Override
+    public String getLabel() {
+        return "WorldEdit Cache";
+    }
+
+    public static ThreadSafeCache getInstance() {
+        return INSTANCE;
+    }
+
+}