Implement RateLimitedLogger to reduce log spamming in some scenarios

src/main/java/de/xite/scoreboard/main/PowerBoard.java

@@ -1,5 +1,6 @@
 package de.xite.scoreboard.main;
 
+import de.xite.scoreboard.utils.RateLimitedLogger;
 import de.xite.scoreboard.versions.VersionSpecific;
 import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
@@ -29,6 +30,7 @@ public class PowerBoard extends JavaPlugin {
 
 	private static Updater updater;
 	private static TPSCalc tpsCalc;
+	private static RateLimitedLogger rateLimitedLogger;
 
 	public static final String permissionPrefix = "powerboard.";
 	public static final int spigotMCPluginID = 73854;
@@ -48,6 +50,7 @@ public void onEnable() {
 		instance = this;
 		updater = new Updater(spigotMCPluginID);
 		tpsCalc = new TPSCalc();
+		rateLimitedLogger = new RateLimitedLogger(this);
 
 		VersionSpecific.init();
 
@@ -152,6 +155,10 @@ public static TPSCalc getTPSCalc() {
 		return tpsCalc;
 	}
 
+	public static RateLimitedLogger getRateLimitedLogger() {
+		return rateLimitedLogger;
+	}
+
 	public static String getPermissionPrefix() {
 		return permissionPrefix;
 	}

src/main/java/de/xite/scoreboard/utils/Placeholders.java

@@ -45,8 +45,11 @@ public static String replace(Player p, String s) {
 		for(CustomPlaceholders ph : ph) {
 			String output = ph.replace(p, s);
 			if(output == null) {
-				pl.getLogger().severe("Output of CustomPlaceholders#replace cannot be null!" +
-						"This is NOT a bug in PowerBoard! It is caused by a CustomPlaceholder which was registered from another plugin.");
+				PowerBoard.getRateLimitedLogger().addSevere(
+						"Output of CustomPlaceholders#replace cannot be null! This is NOT a bug in PowerBoard! " +
+								"It is caused by a CustomPlaceholder that was registered by another plugin.",
+						true
+				);
 			}else
 				s = output;
 		}
@@ -57,9 +60,12 @@ public static String replace(Player p, String s) {
 			try {
 				s = PlaceholderAPI.setPlaceholders(p, s);
 			}catch (Exception e) {
-				pl.getLogger().severe("Could not replace PAPI Placeholders in String "+s+". This is NOT a bug of PowerBoard!"
-						+ "Instead it is caused by an external plugin that provides placeholders to PAPI."
-						+ "It just says PowerBoard there, because PB requests these placeholders from PAPI and therefore is the root cause.");
+				PowerBoard.getRateLimitedLogger().addSevere(
+						"Could not replace PAPI Placeholders in String "+s+". This is NOT a bug of PowerBoard!"
+								+ "Instead it is caused by an external plugin that provides placeholders to PAPI."
+								+ "It just says PowerBoard there, because PB requests these placeholders from PAPI and therefore is the root cause.",
+						true
+				);
 				if(PowerBoard.debug) {
 					e.printStackTrace();
 				}
@@ -72,7 +78,10 @@ public static String replace(Player p, String s) {
 			String newPH = ph.getValue();
 			if(s.contains(oldPH)) {
 				s = s.replace(oldPH, newPH);
-				pl.getLogger().warning("You are using deprecated placeholders! Change "+oldPH+" to "+newPH+" - The old placeholders will be removed soon.");
+				PowerBoard.getRateLimitedLogger().addWarn(
+						"You are using deprecated placeholders! Change "+oldPH+" to "+newPH+" - The old placeholders will be removed soon.",
+						true
+				);
 			}
 		}
 

src/main/java/de/xite/scoreboard/utils/RateLimitedLogger.java

@@ -0,0 +1,83 @@
+package de.xite.scoreboard.utils;
+
+import de.xite.scoreboard.main.PowerBoard;
+import org.bukkit.Bukkit;
+
+import java.util.ArrayList;
+import java.util.logging.Logger;
+
+public class RateLimitedLogger {
+	private PowerBoard pb;
+	private Logger logger;
+
+	private int scheduler;
+	private ArrayList<String> severe = new ArrayList<>();
+	private ArrayList<String> warns = new ArrayList<>();
+	private ArrayList<String> infos = new ArrayList<>();
+
+	public RateLimitedLogger(PowerBoard pb) {
+		this.pb = pb;
+		this.logger = pb.getLogger();
+		startScheduler();
+	}
+
+
+	public void addSevere(String msg, boolean printNow) {
+		if(!severe.contains(msg)) {
+			severe.add(msg);
+			if(printNow)
+				logger.severe(msg);
+		}
+	}
+
+	public void removeSevere(String msg) {
+		severe.remove(msg);
+	}
+
+
+	public void addWarn(String msg, boolean printNow) {
+		if(!warns.contains(msg)) {
+			warns.add(msg);
+			if(printNow)
+				logger.warning(msg);
+		}
+	}
+
+	public void removeWarn(String msg) {
+		warns.remove(msg);
+	}
+
+
+	public void addInfo(String msg, boolean printNow) {
+		if(!infos.contains(msg)) {
+			infos.add(msg);
+			if(printNow)
+				logger.info(msg);
+		}
+	}
+
+	public void removeInfo(String msg) {
+		infos.remove(msg);
+	}
+
+	public void stopScheduler() {
+		Bukkit.getScheduler().cancelTask(scheduler);
+	}
+
+	private void startScheduler() {
+		int interval = 120;
+
+		scheduler = Bukkit.getScheduler().runTaskTimerAsynchronously(pb, this::printLogs, 20 * interval, 20 * interval).getTaskId();
+	}
+
+	private void printLogs() {
+		for(String msg : severe)
+			logger.severe(msg);
+
+		for(String msg : warns)
+			logger.warning(msg);
+
+		for(String msg : infos)
+			logger.info(msg);
+	}
+}