Claim expiration: improvements+config option. Closes #24

- Claim expiration collects all players (uuids) that own claims, and
iterates this set instead of iterating through every single claim.
- Individual claims had a "last modified" timestamp, so this method was
valid before, but makes no sense now since expiration is based on player
inactivity instead of claim inactivity.

New config option under the advanced node allows controlling the
frequency each player in the aforementioned set is checked for
inactivity.

src/main/java/me/ryanhamshire/GriefPrevention/CleanupUnusedClaimPreTask.java

@@ -21,31 +21,33 @@
 import org.bukkit.Bukkit;
 import org.bukkit.OfflinePlayer;
 
+import java.util.UUID;
+
 //asynchronously loads player data without caching it in the datastore, then
 //passes those data to a claim cleanup task which might decide to delete a claim for inactivity
 
 class CleanupUnusedClaimPreTask implements Runnable 
 {	
-	private Claim claim = null;
+	private UUID ownerID = null;
 	
-	CleanupUnusedClaimPreTask(Claim claim)
+	CleanupUnusedClaimPreTask(UUID uuid)
 	{
-		this.claim = claim;
+		this.ownerID = uuid;
 	}
 	
 	@Override
 	public void run()
 	{
 		//get the data
-	    PlayerData ownerData = GriefPrevention.instance.dataStore.getPlayerDataFromStorage(claim.ownerID);
-	    OfflinePlayer ownerInfo = Bukkit.getServer().getOfflinePlayer(claim.ownerID);
+	    PlayerData ownerData = GriefPrevention.instance.dataStore.getPlayerDataFromStorage(ownerID);
+	    OfflinePlayer ownerInfo = Bukkit.getServer().getOfflinePlayer(ownerID);
 	    
 	    //expiration code uses last logout timestamp to decide whether to expire claims
 	    //don't expire claims for online players
 	    if(ownerInfo.isOnline()) return;
 		if(ownerInfo.getLastPlayed() <= 0) return;
 	    
-	    GriefPrevention.AddLogEntry("Looking for expired claims.  Checking data for " + claim.ownerID.toString(), CustomLogEntryTypes.Debug, true);
+	    GriefPrevention.AddLogEntry("Looking for expired claims.  Checking data for " + ownerID.toString(), CustomLogEntryTypes.Debug, true);
 	    
 	    //skip claims belonging to exempted players based on block totals in config
 	    int bonusBlocks = ownerData.getBonusClaimBlocks();
@@ -54,8 +56,25 @@ class CleanupUnusedClaimPreTask implements Runnable
             GriefPrevention.AddLogEntry("Player exempt from claim expiration based on claim block counts vs. config file settings.", CustomLogEntryTypes.Debug, true);
             return;
         }
-		
+
+        Claim claimToExpire = null;
+
+	    for (Claim claim : GriefPrevention.instance.dataStore.getClaims())
+		{
+			if (claim.ownerID.equals(ownerID))
+			{
+				claimToExpire = claim;
+				break;
+			}
+		}
+
+		if (claimToExpire == null)
+		{
+			GriefPrevention.AddLogEntry("Unable to find a claim to expire for " + ownerID.toString(), CustomLogEntryTypes.Debug, false);
+			return;
+		}
+
 	    //pass it back to the main server thread, where it's safe to delete a claim if needed
-	    Bukkit.getScheduler().scheduleSyncDelayedTask(GriefPrevention.instance, new CleanupUnusedClaimTask(claim, ownerData, ownerInfo), 1L);
+	    Bukkit.getScheduler().scheduleSyncDelayedTask(GriefPrevention.instance, new CleanupUnusedClaimTask(claimToExpire, ownerData, ownerInfo), 1L);
 	}
 }

src/main/java/me/ryanhamshire/GriefPrevention/FindUnusedClaimsTask.java

@@ -18,7 +18,10 @@
  
  package me.ryanhamshire.GriefPrevention;
 
-import java.util.Random;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Set;
+import java.util.UUID;
 
 import org.bukkit.Bukkit;
 
@@ -29,38 +32,36 @@ import org.bukkit.Bukkit;
 
 //runs every 1 minute in the main thread
 class FindUnusedClaimsTask implements Runnable 
-{	
-	int nextClaimIndex;
+{
+	private Set<UUID> claimOwnerUUIDs = new HashSet<>();
+	private Iterator<UUID> claimOwnerIterator;
 	
 	FindUnusedClaimsTask()
 	{
-		//start scanning in a random spot
-		if(GriefPrevention.instance.dataStore.claims.size() == 0)
-		{
-			this.nextClaimIndex = 0;
-		}
-		else
-		{
-			Random randomNumberGenerator = new Random();
-			this.nextClaimIndex = randomNumberGenerator.nextInt(GriefPrevention.instance.dataStore.claims.size());
-		}
+		refreshUUIDs();
 	}
 	
 	@Override
 	public void run()
 	{
 		//don't do anything when there are no claims
-		if(GriefPrevention.instance.dataStore.claims.size() == 0) return;
+		if(claimOwnerUUIDs.isEmpty()) return;
 
 		//wrap search around to beginning
-		if(this.nextClaimIndex >= GriefPrevention.instance.dataStore.claims.size()) this.nextClaimIndex = 0;
+		if(!claimOwnerIterator.hasNext())
+		{
+			refreshUUIDs();
+			return;
+		}
 		
-		//decide which claim to check next
-		Claim claim = GriefPrevention.instance.dataStore.claims.get(this.nextClaimIndex++);
-		
-		//skip administrative claims
-		if(claim.isAdminClaim()) return;
-		
-		Bukkit.getScheduler().runTaskAsynchronously(GriefPrevention.instance, new CleanupUnusedClaimPreTask(claim));
+		Bukkit.getScheduler().runTaskAsynchronously(GriefPrevention.instance, new CleanupUnusedClaimPreTask(claimOwnerIterator.next()));
+	}
+
+	public void refreshUUIDs()
+	{
+		claimOwnerUUIDs.clear();
+		for (Claim claim : GriefPrevention.instance.dataStore.claims)
+			claimOwnerUUIDs.add(claim.ownerID);
+		claimOwnerIterator = claimOwnerUUIDs.iterator();
 	}
 }

src/main/java/me/ryanhamshire/GriefPrevention/GriefPrevention.java

@@ -198,6 +198,7 @@ public class GriefPrevention extends JavaPlugin
 	public boolean config_pistonsInClaimsOnly;                      //whether pistons are limited to only move blocks located within the piston's land claim
 
 	public boolean config_advanced_fixNegativeClaimblockAmounts;	//whether to attempt to fix negative claim block amounts (some addons cause/assume players can go into negative amounts)
+	public int config_advanced_claim_expiration_check_rate;			//How often GP should check for expired claims, amount in seconds
 	
 	//custom log settings
 	public int config_logs_daysToKeep;
@@ -327,7 +328,7 @@ public class GriefPrevention extends JavaPlugin
 		
 		//start recurring cleanup scan for unused claims belonging to inactive players
 		FindUnusedClaimsTask task2 = new FindUnusedClaimsTask();
-		this.getServer().getScheduler().scheduleSyncRepeatingTask(this, task2, 20L * 60, 20L * 60);
+		this.getServer().getScheduler().scheduleSyncRepeatingTask(this, task2, 20L * 60, 20L * config_advanced_claim_expiration_check_rate);
 		
 		//register for events
 		PluginManager pluginManager = this.getServer().getPluginManager();
@@ -767,6 +768,7 @@ public class GriefPrevention extends JavaPlugin
         this.databasePassword = config.getString("GriefPrevention.Database.Password", "");
 
         this.config_advanced_fixNegativeClaimblockAmounts = config.getBoolean("GriefPrevention.Advanced.fixNegativeClaimblockAmounts", true);
+        this.config_advanced_claim_expiration_check_rate = config.getInt("GriefPrevention.Advanced.ClaimExpirationCheckRate", 60);
         
         //custom logger settings
         this.config_logs_daysToKeep = config.getInt("GriefPrevention.Abridged Logs.Days To Keep", 7);
@@ -893,6 +895,7 @@ public class GriefPrevention extends JavaPlugin
         outConfig.set("GriefPrevention.BanCommandPattern", this.config_ban_commandFormat);
 
         outConfig.set("GriefPrevention.Advanced.fixNegativeClaimblockAmounts", this.config_advanced_fixNegativeClaimblockAmounts);
+        outConfig.set("GriefPrevention.Advanced.ClaimExpirationCheckRate", this.config_advanced_claim_expiration_check_rate);
 
         //custom logger settings
         outConfig.set("GriefPrevention.Abridged Logs.Days To Keep", this.config_logs_daysToKeep);