Add RamUsage to be safe

BauSystem_Main/src/de/steamwar/bausystem/BauSystem.java

@@ -170,9 +170,7 @@ public class BauSystem extends JavaPlugin implements Listener {
                     }
                     count++;
                     try {
-                        long memorySize = ((com.sun.management.OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean()).getTotalPhysicalMemorySize();
-                        long freeMemory = ((com.sun.management.OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean()).getFreePhysicalMemorySize();
-                        if ((memorySize - freeMemory) / (double) memorySize > 0.8) {
+                        if (RamUsage.getUsage() > 0.8) {
                             Bukkit.shutdown();
                         }
                     } catch (Throwable throwable) {

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

@@ -0,0 +1,36 @@
+/*
+ * This file is a part of the SteamWar software.
+ *
+ * Copyright (C) 2020  SteamWar.de-Serverteam
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.bausystem;
+
+import java.lang.management.ManagementFactory;
+
+public class RamUsage {
+
+    public static double getUsage() {
+        try {
+            long memorySize = ((com.sun.management.OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean()).getTotalPhysicalMemorySize();
+            long freeMemory = ((com.sun.management.OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean()).getFreePhysicalMemorySize();
+            return (memorySize - freeMemory) / (double) memorySize;
+        } catch (Throwable throwable) {
+            return 1D;
+        }
+    }
+
+}