Add RamUsage

BauSystem_Main/src/de/steamwar/bausystem/features/world/RamUsage.java

@@ -19,16 +19,47 @@
 
 package de.steamwar.bausystem.features.world;
 
-import lombok.experimental.UtilityClass;
+import de.steamwar.bausystem.BauSystem;
+import de.steamwar.bausystem.linkage.LinkageType;
+import de.steamwar.bausystem.linkage.Linked;
 import org.bukkit.Bukkit;
+import org.bukkit.boss.BarColor;
+import org.bukkit.boss.BarStyle;
+import org.bukkit.boss.BossBar;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerJoinEvent;
+import org.bukkit.event.player.PlayerQuitEvent;
 
 import java.lang.management.ManagementFactory;
 import java.util.logging.Level;
 
-@UtilityClass
-public class RamUsage {
+@Linked(LinkageType.LISTENER)
+public class RamUsage implements Listener {
 
-    public double getUsage() {
+    private BossBar bossBar;
+
+    public RamUsage() {
+        bossBar = Bukkit.createBossBar("§eRAM", BarColor.YELLOW, BarStyle.SEGMENTED_10);
+        Bukkit.getScheduler().runTaskTimer(BauSystem.getInstance(), () -> {
+            long allocatedMemory = Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory();
+            long presumableFreeMemory = Runtime.getRuntime().maxMemory() - allocatedMemory;
+            double percentageFree = presumableFreeMemory / (double) Runtime.getRuntime().maxMemory();
+            bossBar.setProgress(1 - percentageFree);
+        }, 1, 1);
+    }
+
+    @EventHandler
+    public void onPlayerJoin(PlayerJoinEvent event) {
+        bossBar.addPlayer(event.getPlayer());
+    }
+
+    @EventHandler
+    public void onPlayerQuit(PlayerQuitEvent event) {
+        bossBar.removePlayer(event.getPlayer());
+    }
+
+    public static double getUsage() {
         try {
             long memorySize = ((com.sun.management.OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean()).getTotalPhysicalMemorySize();
             long freeMemory = ((com.sun.management.OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean()).getFreePhysicalMemorySize();