feat: implemented LobbyRunner

Server/src/test/java/uulm/teamname/marvelous/server/lobbymanager/LobbyRunner.java

@@ -0,0 +1,79 @@
+package uulm.teamname.marvelous.server.lobbymanager;
+
+import org.tinylog.Logger;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+
+/**
+ * Class meant for running lobbies. It manages said lobbys, creates threads for it, and moves it into an executor
+ */
+public class LobbyRunner {
+
+    private static LobbyRunner instance;
+
+    static LobbyRunner getInstance() {
+        if (instance == null) {
+            instance = new LobbyRunner();
+        }
+        return instance;
+    }
+
+
+    private final HashMap<LobbyConnection, Thread> activeLobbies;
+
+    private LobbyRunner() {
+        this.activeLobbies = new HashMap<>();
+    }
+
+    /** Starts a new thread for the current LobbyConnection, and adds it to the currently active lobbies */
+    void startLobby(LobbyConnection connection) {
+        Logger.trace("Starting lobby connection thread '{}'", connection.gameID);
+        synchronized (activeLobbies) {
+            if (activeLobbies.containsKey(connection)) {
+                Logger.warn("Already active lobby was started again. This is probably a bug.");
+            } else {
+                Logger.trace("Creating lobby thread 'Lobby-{}'...", connection.gameID);
+                var lobbyThread = new Thread(connection, "Lobby-" + connection.gameID);
+                Logger.trace("Creating mapping from LobbyConnection to newly created thread");
+                activeLobbies.put(connection, lobbyThread);
+                Logger.debug("Starting new lobby thread '{}'", lobbyThread.getName());
+                lobbyThread.start();
+            }
+        }
+    }
+
+    /** Calls {@link Thread#notify()}  on the given lobbyConnection's thread */
+    void notifyLobby(LobbyConnection toNotify) {
+        var lobbyThread = activeLobbies.get(toNotify);
+        if (lobbyThread == null) {
+            Logger.warn("Tried to notify non-existent lobby thread. This is probably a bug.");
+        } else {
+            lobbyThread.notify();
+        }
+    }
+
+    void removeLobby(LobbyConnection lobby) {
+        synchronized (activeLobbies) {
+            var lobbyThread = activeLobbies.get(lobby);
+            if (lobbyThread == null) {
+                Logger.warn("Tried to remove non-existent lobby thread. This is probably a bug.");
+            } else {
+                Logger.debug("Stopping and removing lobby '{}'", lobby.gameID);
+                lobby.terminateConnection();
+                lobbyThread.notify();
+                activeLobbies.remove(lobby);
+            }
+        }
+    }
+
+    /** Shutdown all threads, destroy the lobbies, and close everything up */
+    void shutdownAll() {
+        Logger.info("Stopping and removing all LobbyThreads");
+        activeLobbies.keySet().forEach(this::removeLobby);
+    }
+}