Updating player util.

src/com/massivecraft/mcore4/MCore.java

@@ -31,7 +31,8 @@ public class MCore extends JavaPlugin
 	{
 		logPrefix = "["+this.getDescription().getName()+"] ";
 		
-		PlayerUtil.populateAllVisitorNames();
+		// Setup PlayerUtil and it's events
+		new PlayerUtil(this);
 		
 		// This is safe since all plugins using Persist should bukkit-depend this plugin.
 		Persist.instances.clear();

src/com/massivecraft/mcore4/util/PlayerUtil.java

@@ -2,8 +2,12 @@ package com.massivecraft.mcore4.util;
 
 import java.io.File;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
+import java.util.Map.Entry;
+import java.util.concurrent.ConcurrentSkipListMap;
+import java.util.regex.Pattern;
 
 import net.minecraft.server.DedicatedServer;
 import net.minecraft.server.EntityPlayer;
@@ -13,36 +17,78 @@ import org.bukkit.Bukkit;
 import org.bukkit.craftbukkit.CraftServer;
 import org.bukkit.craftbukkit.entity.CraftPlayer;
 import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerPreLoginEvent;
+import org.bukkit.plugin.Plugin;
 
-public class PlayerUtil
+public class PlayerUtil implements Listener
 {
-	private static Set<String> allVisitorNames = new TreeSet<String>(String.CASE_INSENSITIVE_ORDER);
+	// -------------------------------------------- //
-	public static Set<String> getAllVisitorNames() { return allVisitorNames; }
+	// FIELDS
-	public static void populateAllVisitorNames()
+	// -------------------------------------------- //
-	{
-		// Find the player folder
-	    CraftServer cserver = (CraftServer)Bukkit.getServer();
-	    DedicatedServer dserver = (DedicatedServer)cserver.getServer();
-		String levelName = dserver.propertyManager.getString("level-name", "world");
-		File playerfolder = new File(Bukkit.getWorldContainer(), new File(levelName, "players").getPath());
 	
-		// Populate by removing .dat
+	/**
-		for (File playerfile : playerfolder.listFiles())
+	 * This is the latest created instance of this class.
+	 */
+	private static PlayerUtil i = null;
+	
+	/**
+	 * We will use this folder later. 
+	 */
+	public static File playerfolder = getPlayerFolder();
+	
+	/**
+	 * This map is populated using the player.dat files on disk.
+	 * It is also populated when a player tries to log in to the server.
+	 */
+	protected static Map<String, String> nameToCorrectName = new ConcurrentSkipListMap<String, String>(String.CASE_INSENSITIVE_ORDER);
+	
+	/**
+	 * This map is used to improve the speed of name start lookups.
+	 * Note that the keys in this map is lowercase.
+	 */
+	protected static Map<String, Set<String>> lowerCaseStartOfNameToCorrectNames = new ConcurrentSkipListMap<String, Set<String>>();
+	
+	// -------------------------------------------- //
+	// CONSTRUCTOR AND EVENT LISTENER
+	// -------------------------------------------- //
+	
+	public PlayerUtil(Plugin plugin)
+	{
+		if (i != null) return;
+		i = this;
+		Bukkit.getPluginManager().registerEvents(this, plugin);
+		populateCaseInsensitiveNameToCaseCorrectName();
+	}
+	
+	@EventHandler(priority = EventPriority.LOWEST)
+	public void onLowestPlayerPreLoginEvent(PlayerPreLoginEvent event)
+	{
+		String newPlayerName = event.getName();
+		String lowercaseNewPlayerName = newPlayerName.toLowerCase();
+		
+		// Add this name to the case-corrector map
+		nameToCorrectName.put(newPlayerName, newPlayerName);
+		
+		// Update the cache
+		for (Entry<String, Set<String>> entry : lowerCaseStartOfNameToCorrectNames.entrySet())
 		{
-			String filename = playerfile.getName();
+			if (lowercaseNewPlayerName.startsWith(entry.getKey()))
-			String playername = filename.substring(0, filename.length()-4);
+			{
-			allVisitorNames.add(playername);
+				entry.getValue().add(newPlayerName);
+			}
 		}
 	}
 	
-	public static void sendHealthFoodUpdatePacket(Player player)
+	// -------------------------------------------- //
-	{
+	// PUBLIC METHODS
-		CraftPlayer cplayer = (CraftPlayer)player;
+	// -------------------------------------------- //
-		EntityPlayer eplayer = cplayer.getHandle();
-		eplayer.netServerHandler.sendPacket(new Packet8UpdateHealth(eplayer.getHealth(), eplayer.getFoodData().a(), eplayer.getFoodData().e()));
-	}
 	
-	// TODO: Is there synchronization/parallelism risks here?
+	/**
+	 * This is a faster version of the getPlayerExact method since this one is exact for real (no to lower case stuff).
+	 */
 	@SuppressWarnings("unchecked")
 	public static Player getPlayerExact(String exactPlayerName)
 	{
@@ -55,7 +101,154 @@ public class PlayerUtil
 			{
 				return player;
 			}
-        }
+		}
 		return null;
 	}
+	
+	/**
+	 * This method simply checks if the playerName is a valid one.
+	 * Mojangs rules for Minecraft character registration is used.
+	 */
+	public static boolean isValidPlayerName(final String playerName)
+	{
+		return Pattern.matches("^[a-zA-Z0-9_]{2,16}$", playerName);
+	}
+	
+	public static Set<String> getAllVisitorNames()
+	{
+		return nameToCorrectName.keySet();
+	}
+	
+	/**
+	 * This method takes a player name and returns the same name but with correct case.
+	 * Null is returned if the correct case can not be determined.
+	 */
+	public static String fixPlayerNameCase(final String playerName)
+	{
+		return nameToCorrectName.get(playerName);
+	}
+	
+	/**
+	 * Find all player names starting with a certain string (not case sensitive).
+	 * This method will return the names of offline players as well as online players.
+	 */
+	public static Set<String> getAllPlayerNamesCaseinsensitivelyStartingWith(final String startOfName)
+	{
+		Set<String> ret = new TreeSet<String>(String.CASE_INSENSITIVE_ORDER);
+		
+		String lowercaseStartOfName = startOfName.toLowerCase();
+		
+		// Try to fetch from the cache
+		Set<String> cachedNames = lowerCaseStartOfNameToCorrectNames.get(lowercaseStartOfName);
+		if (cachedNames != null)
+		{
+			ret.addAll(cachedNames);
+			return ret;
+		}
+		
+		// Build it the hard way if cache did not exist
+		
+		ret = new TreeSet<String>(String.CASE_INSENSITIVE_ORDER);
+		for (String correctName : nameToCorrectName.values())
+		{
+			if (correctName.toLowerCase().startsWith(lowercaseStartOfName))
+			{
+				ret.add(correctName);
+			}
+		}
+		
+		// Add it to the cache
+		Set<String> shallowCopyForCache = new TreeSet<String>(String.CASE_INSENSITIVE_ORDER);
+		shallowCopyForCache.addAll(ret);
+		lowerCaseStartOfNameToCorrectNames.put(lowercaseStartOfName, shallowCopyForCache);
+		
+		return ret;
+	}
+	
+	/**
+	 * In Minecraft a playername can be 16 characters long. One sign line is however only 15 characters long.
+	 * If we find a 15 character long playername on a sign it could thus refer to more than one player.
+	 * This method finds all possible matching player names.
+	 */
+	public static Set<String> interpretPlayerNameFromSign(String playerNameFromSign)
+	{
+		Set<String> ret = new TreeSet<String>(String.CASE_INSENSITIVE_ORDER);
+		
+		if (playerNameFromSign.length() > 15)
+		{
+			// This case will in reality not happen.
+			ret.add(playerNameFromSign);
+			return ret;
+		}
+		
+		if (playerNameFromSign.length() == 15)
+		{
+			ret.addAll(PlayerUtil.getAllPlayerNamesCaseinsensitivelyStartingWith(playerNameFromSign));
+		}
+		else
+		{
+			String fixedPlayerName = PlayerUtil.fixPlayerNameCase(playerNameFromSign);
+			if (fixedPlayerName != null)
+			{
+				ret.add(fixedPlayerName);
+			}
+		}
+		
+		return ret;
+	}
+	
+	/**
+	 * It seems the OfflinePlayer#getLastPlayed in Bukkit is broken.
+	 * It occasionally returns invalid values. Therefore we use this instead.
+	 * The playerName must be the full name but is not case sensitive. 
+	 */
+	public static long getLastPlayed(String playerName)
+	{
+		String playerNameCC = fixPlayerNameCase(playerName);
+		if (playerNameCC == null) return 0;
+			
+		Player player = Bukkit.getPlayerExact(playerNameCC);
+		if (player != null && player.isOnline()) return System.currentTimeMillis();
+		
+		File playerFile = new File(playerfolder, playerNameCC+".dat");
+		return playerFile.lastModified();
+	}
+	
+	/**
+	 * Updates the players food and health information.
+	 */
+	public static void sendHealthFoodUpdatePacket(Player player)
+	{
+		CraftPlayer cplayer = (CraftPlayer)player;
+		EntityPlayer eplayer = cplayer.getHandle();
+		eplayer.netServerHandler.sendPacket(new Packet8UpdateHealth(eplayer.getHealth(), eplayer.getFoodData().a(), eplayer.getFoodData().e()));
+	}
+	
+	// -------------------------------------------- //
+	// INTERNAL METHODS
+	// -------------------------------------------- //
+	
+	protected static void populateCaseInsensitiveNameToCaseCorrectName()
+	{   
+		// Populate by removing .dat
+		for (File playerfile : playerfolder.listFiles())
+		{
+			String filename = playerfile.getName();
+			String playername = filename.substring(0, filename.length()-4);
+			nameToCorrectName.put(playername, playername);
+		}
+	}
+	
+	/**
+	 * You might ask yourself why we do this in such a low-level way.
+	 * The reason is this info is not yet "compiled" for plugins that init early.
+	 */
+	protected static File getPlayerFolder()
+	{
+		CraftServer cserver = (CraftServer)Bukkit.getServer();
+		DedicatedServer dserver = (DedicatedServer)cserver.getServer();
+		String levelName = dserver.propertyManager.getString("level-name", "world");
+		return new File(Bukkit.getWorldContainer(), new File(levelName, "players").getPath());
+	}
+	
 }