.gitlab-ci.yml

@@ -6,11 +6,13 @@ stages:
 
 # Reusable definitions
 .gradle-cache: &gradle-cache
+  variables:
+    GRADLE_USER_HOME: '$CI_PROJECT_DIR/.gradle-home'
   cache:
     key: '$CI_PROJECT_ID-gradle'
     paths:
       - .gradle/
-      - ~/.gradle/caches/
+      - .gradle-home/
 
 .on-commit: &on-commit
   rules:
@@ -22,7 +24,7 @@ stages:
 .on-mr: &on-mr
   rules:
     - if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
-      allow_failure: true   # deactivate after all issues (shown by checkstyle) have been resolved
+      allow_failure: false
 
 # Jobs
 checkstyle:
@@ -30,7 +32,7 @@ checkstyle:
     stage: lint
     image: gradle:9.3.1-jdk25
     script:
-        - gradle checkstyleMain checkstyleTest
+        - gradle checkstyleMain checkstyleTest --configuration-cache --configuration-cache-problems=warn
     allow_failure: true
     artifacts:
         when: always
@@ -47,8 +49,8 @@ checkstyle-mr:
     stage: lint
     image: gradle:9.3.1-jdk25
     script:
-        - gradle checkstyleMain checkstyleTest
-    allow_failure: true
+        - gradle checkstyleMain checkstyleTest --configuration-cache --configuration-cache-problems=warn
+    allow_failure: false
     artifacts:
         when: always
         paths:
@@ -66,6 +68,7 @@ checkstyle-report:
         - job: checkstyle-mr
           artifacts: true
           optional: true
+    when: always
     rules:
         - if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
     script:
@@ -81,7 +84,7 @@ compile-check:
     stage: build
     image: gradle:9.3.1-jdk25
     script:
-        - gradle compileTestJava
+        - gradle compileTestJava --configuration-cache --configuration-cache-problems=warn
     needs: []
     rules:
         - if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
@@ -89,12 +92,20 @@ compile-check:
         - if: '$CI_COMMIT_BRANCH'
           allow_failure: false
 
+javadoc-check:
+    <<: [*gradle-cache, *on-mr]
+    stage: build
+    image: gradle:9.3.1-jdk25
+    script:
+        - gradle javaDoc --configuration-cache --configuration-cache-problems=warn
+    needs: []
+
 test:
     <<: *gradle-cache
     stage: test
     image: gradle:9.3.1-jdk25
     script:
-        - gradle test
+        - gradle test --configuration-cache --configuration-cache-problems=warn
     artifacts:
         when: always
         reports:

.gitlab/issue_templates/Bug Report.md

@@ -34,7 +34,7 @@
 
 ### Checklist
 - [ ] I reproduced the problem using the steps above
-- [ ] I searched documentation docs for relevant information
+- [ ] I searched documentation for relevant information
 - [ ] I added relevant labels
 
 /label ~bug

.gitlab/issue_templates/Feature Request.md

@@ -11,8 +11,8 @@
 <!-- Detailed description of the desired behavior -->
 
 ### Checklist
-- [ ] I reproduced the problem using the steps above
-- [ ] I searched documentation docs for relevant information
+- [ ] I have described the function in detail
+- [ ] I searched docs for alternative implementations matching my needs
 - [ ] I added relevant labels
 
 /label ~enhancement

build.gradle

@@ -108,3 +108,17 @@ tasks.register('fatJar', Jar) {
         configurations.runtimeClasspath.collect { it.isDirectory() ? it : zipTree(it) }
     })
 }
+
+    tasks.register('javadocJar', Jar) {
+        group = 'build'
+        description = 'Assembles a Javadoc JAR.'
+        dependsOn tasks.named('javadoc')
+        archiveClassifier = 'javadoc'
+        from(tasks.javadoc.destinationDir)
+    }
+
+    tasks.register('build-cs108') {
+        group = 'build'
+        description = 'Produces executable JAR and Javadoc JAR for CS108.'
+        dependsOn tasks.named('fatJar'), tasks.named('javadocJar')
+    }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ClientApp.java

@@ -10,15 +10,15 @@ import org.apache.logging.log4j.Logger;
 /**
  * Entry point for the Casono client application. Handles client startup and connection parameters.
  *
- * <p>Standardkonstruktor für die Anwendung.
+ * <p>Default constructor for the application.
  */
 public class ClientApp {
 
     private static final Logger LOGGER = LogManager.getLogger(ClientApp.class);
 
-    /** Standardkonstruktor. */
+    /** Default constructor. */
     public ClientApp() {
-        // Standardkonstruktor
+        // Default constructor
     }
 
     /**

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/Launcher.java

@@ -6,13 +6,13 @@ import javafx.application.Application;
 /**
  * Launcher for the Casono main UI.
  *
- * <p>Standardkonstruktor für die Anwendung.
+ * <p>Default constructor for the application.
  */
 public class Launcher {
 
-    /** Standardkonstruktor. */
+    /** Default constructor. */
     public Launcher() {
-        // Standardkonstruktor
+        // Default constructor
     }
 
     /**

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/chatui/ChatController.java

@@ -41,6 +41,11 @@ public class ChatController {
         chatScrollPane.vvalueProperty().bind(chatVBox.heightProperty());
     }
 
+    /** Standardkonstruktor. Wird von FXML verwendet. */
+    public ChatController() {
+        // default constructor for FXML
+    }
+
     /**
      * Diese Methode wird vom Senden-Button oder Enter ausgelöst. Sie gibt die eigene Nachricht an
      * das Netzwerkprotokoll weiter.

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/gameui/CasinoGameController.java

@@ -15,11 +15,22 @@ import javafx.scene.layout.VBox;
  */
 public class CasinoGameController {
 
+    /** Standardkonstruktor. Wird von FXML verwendet. */
+    public CasinoGameController() {
+        // default constructor for FXML
+    }
+
     @FXML private Label welcomeText;
     @FXML private VBox casinoTable;
 
     // TODO: Test-Logik: wird durch echte Spielinteraktionen ersetzt,
     // sobald die GameEngine fertig ist
+
+    /**
+     * Temporäre Test-Methode, die bei Klick auf den Tisch eine Platzhalteraktion ausführt.
+     *
+     * <p>Wird in der finalen Implementierung durch die Spiel-Logik ersetzt.
+     */
     @FXML
     public void onTableClick() {
         welcomeText.setText("Einsatz akzeptiert!");

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/gameui/CasinoGameUI.java

@@ -17,6 +17,11 @@ import javafx.stage.Stage;
  */
 public class CasinoGameUI extends Application {
 
+    /** Standardkonstruktor. */
+    public CasinoGameUI() {
+        // default no-arg constructor
+    }
+
     private static final int DEFAULT_WIDTH = 1200;
     private static final int DEFAULT_HEIGHT = 800;
 
@@ -29,7 +34,7 @@ public class CasinoGameUI extends Application {
     @Override
     public void start(Stage stage) throws IOException {
         FXMLLoader fxmlLoader =
-                new FXMLLoader(CasinoGameUI.class.getResource("/ui-structure/casinogameui.fxml"));
+                new FXMLLoader(CasinoGameUI.class.getResource("/ui-structure/Casinogameui.fxml"));
         Scene scene = new Scene(fxmlLoader.load(), DEFAULT_WIDTH, DEFAULT_HEIGHT);
         stage.setTitle("Casono (GAME)");
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/gameui/gameuicomponents/CasinoBrowserController.java

@@ -27,6 +27,8 @@ import javafx.scene.shape.Rectangle;
 import javafx.scene.web.WebEngine;
 import javafx.scene.web.WebView;
 import javafx.stage.Stage;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 /**
  * Experimenteller integrierter Browser für Casono.
@@ -50,13 +52,17 @@ import javafx.stage.Stage;
  */
 public class CasinoBrowserController {
 
+    /** Standardkonstruktor. Initialisiert den CasinoBrowserController. */
+    public CasinoBrowserController() {
+        // Intentionally left blank; controller initialization is FXML-driven.
+    }
+
     private static final Set<String> TRUSTED_DOMAINS = new HashSet<>();
 
     private static final CookieManager COOKIE_MANAGER =
             new CookieManager(null, CookiePolicy.ACCEPT_ORIGINAL_SERVER);
 
-    private static final org.apache.logging.log4j.Logger LOGGER =
-            org.apache.logging.log4j.LogManager.getLogger(CasinoBrowserController.class);
+    private static final Logger LOGGER = LogManager.getLogger(CasinoBrowserController.class);
 
     private static final int LOGO_HEIGHT = 40;
     private static final int CORNER_RADIUS = 40;
@@ -354,8 +360,9 @@ public class CasinoBrowserController {
         fwdBtn.getStyleClass().add("gray-button");
         fwdBtn.setOnAction(
                 e -> {
-                    if (engine.getHistory().getCurrentIndex()
-                            < engine.getHistory().getEntries().size() - 1) {
+                    int currentIndex = engine.getHistory().getCurrentIndex();
+                    int lastIndex = engine.getHistory().getEntries().size() - 1;
+                    if (currentIndex < lastIndex) {
                         engine.getHistory().go(1);
                     }
                 });
@@ -423,7 +430,7 @@ public class CasinoBrowserController {
 
         Scene scene = new Scene(root, WINDOW_WIDTH, WINDOW_HEIGHT);
 
-        var css = CasinoBrowserController.class.getResource("/ui-structure/casinogameui.css");
+        var css = CasinoBrowserController.class.getResource("/ui-structure/Casinogameui.css");
 
         if (css != null) {
             scene.getStylesheets().add(css.toExternalForm());
@@ -512,10 +519,11 @@ public class CasinoBrowserController {
 
         alert.setTitle("Unbekannte Website");
         alert.setHeaderText("Diese Website ist nicht bekannt");
-        alert.setContentText(
+        String content =
                 host
-                        + "\n\nDiese Seite ist nicht vom "
-                        + "Casono Browser verifiziert.\nMöchten Sie sie trotzdem öffnen?");
+                        + "\n\nDiese Seite ist nicht vom Casono Browser verifiziert.\n"
+                        + "Möchten Sie sie trotzdem öffnen?";
+        alert.setContentText(content);
 
         var stream = CasinoBrowserController.class.getResourceAsStream(LOGO_PATH);
         Image logo = new Image(stream);

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/gameui/gameuicomponents/TaskbarController.java

@@ -1,12 +1,14 @@
 package ch.unibas.dmi.dbis.cs108.casono.client.ui.gameui.gameuicomponents;
 
-import javafx.application.Platform;
+import ch.unibas.dmi.dbis.cs108.casono.client.ui.lobbyui.Casinomainui;
 import javafx.fxml.FXML;
 import javafx.scene.control.TextField;
 import javafx.scene.input.KeyCode;
 import javafx.scene.input.KeyEvent;
 import javafx.scene.input.MouseEvent;
 import javafx.scene.layout.HBox;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 /**
  * Controller für die interaktive Taskleiste innerhalb der Poker-UI.
@@ -16,8 +18,12 @@ import javafx.scene.layout.HBox;
  */
 public class TaskbarController {
 
-    private static final org.apache.logging.log4j.Logger LOGGER =
-            org.apache.logging.log4j.LogManager.getLogger(CasinoBrowserController.class);
+    /** Standardkonstruktor. Wird von FXML verwendet. */
+    public TaskbarController() {
+        // default constructor for FXML
+    }
+
+    private static final Logger LOGGER = LogManager.getLogger(CasinoBrowserController.class);
 
     @FXML private HBox taskbar;
     @FXML private TextField taskbarInput;
@@ -92,15 +98,21 @@ public class TaskbarController {
         processBet();
     }
 
-    /**
-     * Wird aufgerufen, wenn der Exit-Button in der Taskleiste gedrückt wird.
-     *
-     * <p>TODO: Logik implementieren, um zur Lobby zurückzukehren, ohne die gesamte Anwendung zu
-     * schließen (kein System.exit/Platform.exit).
-     */
     @FXML
     private void onExitButtonClick() {
-        Platform.exit();
+        javafx.application.Platform.runLater(
+                () -> {
+                    // Close game stage
+                    javafx.stage.Stage currentStage =
+                            (javafx.stage.Stage) taskbar.getScene().getWindow();
+                    currentStage.close();
+                    // Lobby-UI starten
+                    try {
+                        new Casinomainui().start(new javafx.stage.Stage());
+                    } catch (Exception e) {
+                        LOGGER.error("Fehler beim Starten der Lobby-UI: {}", e.getMessage());
+                    }
+                });
     }
 
     /**

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/lobbyui/Casinomainui.java

@@ -10,13 +10,13 @@ import javafx.stage.Stage;
 /**
  * JavaFX Application class for the Casono main UI.
  *
- * <p>Standardkonstruktor für die Anwendung.
+ * <p>Default constructor for the application.
  */
 public class Casinomainui extends Application {
 
-    /** Standardkonstruktor. */
+    /** Default constructor. */
     public Casinomainui() {
-        // Standardkonstruktor
+        // Default constructor
     }
 
     private static final int SCENE_WIDTH = 1200;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/lobbyui/CasinomainuiController.java

@@ -28,6 +28,7 @@ public class CasinomainuiController {
     private LobbyButtonGridManager gridManager;
     private int nextButtonId = 1;
 
+    /** Default constructor for dependency injection by FXMLLoader. */
     public CasinomainuiController() {
         // Default constructor
     }
@@ -39,7 +40,7 @@ public class CasinomainuiController {
         subtitleLabel.setText("Texas Hold'em Poker");
         logoView.setImage(new Image(getClass().getResource("/images/logo.png").toExternalForm()));
 
-        translationManager = new LobbyButtonTranslationManager();
+        translationManager = LobbyButtonTranslationManager.getInstance();
         gridManager =
                 new LobbyButtonGridManager(new javafx.scene.layout.GridPane(), translationManager);
         casinoTable.getChildren().clear();
@@ -57,7 +58,7 @@ public class CasinomainuiController {
     @FXML
     public void handleCreateLobbyButton() {
         if (translationManager.isFull()) {
-            LOGGER.warn("Grid voll! Keine weiteren Lobbys moeglich.");
+            LOGGER.warn("Grid is full! No more lobbies available.");
             return;
         }
         int buttonId = nextButtonId++;
@@ -67,7 +68,7 @@ public class CasinomainuiController {
             LOGGER.info("ButtonID: {}, LobbyID: {}", buttonId, lobbyId);
             gridManager.renderLobbyButtons();
         } catch (Exception e) {
-            LOGGER.error("Fehler beim Hinzufügen: {}", e.getMessage());
+            LOGGER.error("Error while adding lobby button: {}", e.getMessage());
         }
     }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/lobbyui/LobbyButtonGridManager.java

@@ -17,6 +17,8 @@ import org.apache.logging.log4j.Logger;
  * ButtonID to LobbyID.
  */
 public class LobbyButtonGridManager {
+    private static final double BUTTON_WIDTH_MARGIN = 20.0;
+    private static final double BUTTON_MIN_SIZE = 10.0;
     private static final Logger LOGGER = LogManager.getLogger(LobbyButtonGridManager.class);
 
     /** GridPane for the button grid. */
@@ -46,7 +48,8 @@ public class LobbyButtonGridManager {
     public LobbyButtonGridManager(
             GridPane gridPane, LobbyButtonTranslationManager translationManager) {
         this.gridPane = gridPane;
-        this.translationManager = translationManager;
+        // Singleton immer verwenden
+        this.translationManager = LobbyButtonTranslationManager.getInstance();
     }
 
     /**
@@ -65,8 +68,21 @@ public class LobbyButtonGridManager {
             int buttonId = entry.getKey();
             Button btn = new Button();
             btn.setId("lobbyBtn-" + buttonId);
-            btn.setGraphic(
-                    new ImageView(new Image(getClass().getResourceAsStream(BUTTON_IMAGE_PATH))));
+            ImageView imageView =
+                    new ImageView(new Image(getClass().getResourceAsStream(BUTTON_IMAGE_PATH)));
+            imageView.setPreserveRatio(true);
+            // Dynamische Breite: Bindung an die Zellengröße
+            imageView
+                    .fitWidthProperty()
+                    .bind(gridPane.widthProperty().divide(COLS).subtract(BUTTON_WIDTH_MARGIN));
+            imageView.setSmooth(true);
+            btn.setGraphic(imageView);
+            btn.setMaxWidth(Double.MAX_VALUE);
+            btn.setMaxHeight(Double.MAX_VALUE);
+            btn.setMinWidth(BUTTON_MIN_SIZE);
+            btn.setMinHeight(BUTTON_MIN_SIZE);
+            GridPane.setHgrow(btn, javafx.scene.layout.Priority.ALWAYS);
+            GridPane.setVgrow(btn, javafx.scene.layout.Priority.ALWAYS);
             btn.setOnAction(
                     e -> {
                         Integer lobbyId = translationManager.getLobbyIdForButton(buttonId);
@@ -99,8 +115,22 @@ public class LobbyButtonGridManager {
      * @param lobbyId The lobbyId to join
      */
     public void joinLobby(int lobbyId) {
-        // TODO: Replace with actual join logic
+        // Game-UI starten und Lobby-UI schließen
         LOGGER.info("Joining lobby: {}", lobbyId);
+        javafx.application.Platform.runLater(
+                () -> {
+                    // Lobby-Stage schließen
+                    javafx.stage.Stage currentStage =
+                            (javafx.stage.Stage) gridPane.getScene().getWindow();
+                    currentStage.close();
+                    // Game-UI starten
+                    try {
+                        new ch.unibas.dmi.dbis.cs108.casono.client.ui.gameui.CasinoGameUI()
+                                .start(new javafx.stage.Stage());
+                    } catch (Exception e) {
+                        LOGGER.error("Fehler beim Starten der Game-UI: {}", e.getMessage());
+                    }
+                });
     }
 
     /**

src/main/java/ch/unibas/dmi/dbis/cs108/casono/client/ui/lobbyui/LobbyButtonTranslationManager.java

@@ -4,36 +4,53 @@ import java.util.HashMap;
 import java.util.Map;
 
 /**
- * Verwaltet das Mapping zwischen Button-IDs und Lobby-IDs rein im Speicher. Keine Dateioperationen,
- * nur Laufzeitdatenstruktur.
+ * Manages the mapping between Button IDs and Lobby IDs in memory only. No file operations,
+ * runtime-only data structure.
  */
 public class LobbyButtonTranslationManager {
-    /** Maximale Anzahl an Buttons/Lobbys */
+
+    // Singleton instance
+    private static LobbyButtonTranslationManager instance;
+
+    // Singleton access
+    /**
+     * Returns the singleton instance of the manager.
+     *
+     * @return the single instance of {@code LobbyButtonTranslationManager}
+     */
+    public static LobbyButtonTranslationManager getInstance() {
+        if (instance == null) {
+            instance = new LobbyButtonTranslationManager();
+        }
+        return instance;
+    }
+
+    /** Maximum number of buttons/lobbies */
     private static final int MAX_BUTTONS = 8;
 
-    /** Zuordnung ButtonID → LobbyID */
+    /** Mapping ButtonID → LobbyID */
     private final Map<Integer, Integer> buttonIdToLobbyId = new HashMap<>();
 
-    /** Konstruktor: initialisiert die Zuordnung leer. */
-    public LobbyButtonTranslationManager() {
-        // Zuordnung bleibt leer beim Start
+    /** Private constructor for the singleton pattern */
+    private LobbyButtonTranslationManager() {
+        // Mapping is empty at startup
     }
 
     /**
-     * Prüft, ob das Grid voll ist (MAX_BUTTONS erreicht).
+     * Checks whether the grid is full (MAX_BUTTONS reached).
      *
-     * @return true, wenn Grid voll; sonst false
+     * @return true if the grid is full; otherwise false
      */
     public boolean isFull() {
         return buttonIdToLobbyId.size() >= MAX_BUTTONS;
     }
 
     /**
-     * Fügt eine Zuordnung ButtonID → LobbyID hinzu.
+     * Adds a mapping ButtonID → LobbyID.
      *
-     * @param buttonId Die ID des Buttons
-     * @param lobbyId Die ID der Lobby
-     * @throws Exception wenn das Grid voll ist
+     * @param buttonId the ID of the button
+     * @param lobbyId the ID of the lobby
+     * @throws Exception when the grid is full
      */
     public void addLobbyButton(int buttonId, int lobbyId) throws Exception {
         if (isFull()) {
@@ -43,28 +60,28 @@ public class LobbyButtonTranslationManager {
     }
 
     /**
-     * Entfernt eine Zuordnung für die gegebene ButtonID.
+     * Removes the mapping for the given ButtonID.
      *
-     * @param buttonId Die ID des zu entfernenden Buttons
+     * @param buttonId the ID of the button to remove
      */
     public void removeLobbyButton(int buttonId) {
         buttonIdToLobbyId.remove(buttonId);
     }
 
     /**
-     * Gibt die LobbyID für eine gegebene ButtonID zurück.
+     * Returns the LobbyID for a given ButtonID.
      *
-     * @param buttonId Die ButtonID
-     * @return Die zugehoerige LobbyID oder null, falls nicht vorhanden
+     * @param buttonId the ButtonID
+     * @return the associated LobbyID or null if not present
      */
     public Integer getLobbyIdForButton(int buttonId) {
         return buttonIdToLobbyId.get(buttonId);
     }
 
     /**
-     * Gibt die gesamte Zuordnung ButtonID → LobbyID zurück.
+     * Returns the full mapping ButtonID → LobbyID.
      *
-     * @return Map aller Zuordnungen
+     * @return Map of all mappings
      */
     public Map<Integer, Integer> getButtonIdToLobbyId() {
         return buttonIdToLobbyId;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/ServerApp.java

@@ -3,10 +3,11 @@ package ch.unibas.dmi.dbis.cs108.casono.server;
 import ch.unibas.dmi.dbis.cs108.casono.server.domain.user.UserCleanupJob;
 import ch.unibas.dmi.dbis.cs108.casono.server.domain.user.UserRegistry;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.NetworkManager;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.command.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.CommandParserDispatcher;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.DisconnectEvent;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.CommandParserDispatcher;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionDisconnectJob;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionManager;
 import java.time.Duration;
 import java.util.concurrent.Executors;
@@ -17,9 +18,12 @@ import org.apache.logging.log4j.Logger;
 
 /** Application class for starting the server. */
 public class ServerApp {
-    public static final int USER_CLEANUP_JOB_DELAY = 0;
-    public static final int USER_CLEANUP_JOB_PERIOD = 10;
-    public static final int USER_CLEANUP_JOB_RECONNECT_THRESHOLD = 10;
+    private static final int USER_CLEANUP_JOB_DELAY = 0;
+    private static final int USER_CLEANUP_JOB_PERIOD = 10;
+    private static final int USER_CLEANUP_JOB_RECONNECT_THRESHOLD = 10;
+    private static final int SESSION_DISCONNECT_JOB_DELAY = 0;
+    private static final int SESSION_DISCONNECT_JOB_PERIOD = 2;
+    private static final int SESSION_DISCONNECT_JOB_TIMEOUT = 5;
 
     public static void start(String arg) {
         int port = Integer.parseInt(arg);
@@ -45,6 +49,14 @@ public class ServerApp {
                 USER_CLEANUP_JOB_DELAY,
                 USER_CLEANUP_JOB_PERIOD,
                 TimeUnit.SECONDS);
+        scheduler.scheduleAtFixedRate(
+                new SessionDisconnectJob(
+                        sessionManager,
+                        eventBus,
+                        Duration.ofSeconds(SESSION_DISCONNECT_JOB_TIMEOUT)),
+                SESSION_DISCONNECT_JOB_DELAY,
+                SESSION_DISCONNECT_JOB_PERIOD,
+                TimeUnit.SECONDS);
 
         networkManager.start();
     }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/domain/user/UserRegistry.java

@@ -58,7 +58,6 @@ public class UserRegistry {
      *
      * @param sessionId the session ID of the disconnected client
      */
-    // TODO: Add to EventRegistry with DisconnectEvent
     public synchronized void onDisconnect(SessionId sessionId) {
         User user = bySessionId.remove(sessionId);
         if (user == null) {

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/CommandHandler.java

@@ -1,7 +0,0 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.command;
-
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.Request;
-
-public interface CommandHandler<T extends Request> {
-    void execute(T request);
-}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/execution/CommandHandler.java

@@ -0,0 +1,7 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Request;
+
+public interface CommandHandler<T extends Request> {
+    void execute(T request);
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/execution/CommandRouter.java

@@ -1,6 +1,6 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.command;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.Request;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Request;
 import java.util.HashMap;
 import java.util.Map;
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/execution/UnknownRequestException.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.command;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution;
 
 public class UnknownRequestException extends RuntimeException {
     private final String requestName;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/parsing/CommandParser.java

@@ -0,0 +1,18 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.PrimitiveRequest;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Request;
+
+/**
+ * Parser to convert the PrimitiveRequest to a Request and performing checks for required fields and
+ * data types
+ */
+public interface CommandParser<T extends Request> {
+    /**
+     * Parses the provided PrimitiveRequest into a command-specific request
+     *
+     * @param primitiveRequest
+     * @return
+     */
+    T parse(PrimitiveRequest primitiveRequest);
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/parsing/CommandParserDispatcher.java

@@ -1,5 +1,7 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing;
 
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.PrimitiveRequest;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Request;
 import java.util.HashMap;
 import java.util.Map;
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/parsing/RequestParameter.java

@@ -0,0 +1,4 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing;
+
+/** Used in the PrimitiveRequest class to store the key of a parameter with its respective value */
+public record RequestParameter(String key, String value) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/command/parsing/UnknownCommandException.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing;
 
 /**
  * Exception thrown when the CommandParserDispatcher has no registered handler for the provided

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/parser/CommandParser.java

@@ -1,15 +0,0 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
-
-/**
- * Parser to convert the PrimitiveRequest to a Request and performing checks for required fields and
- * data types
- */
-public interface CommandParser {
-    /**
-     * Parses the provided PrimitiveRequest into a command-specific request
-     *
-     * @param primitiveRequest
-     * @return
-     */
-    Request parse(PrimitiveRequest primitiveRequest);
-}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/parser/Parameter.java

@@ -1,4 +0,0 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
-
-/** Used in the PrimitiveRequest class to store the key of a parameter with its respective value */
-public record Parameter(String key, String value) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/parser/PrimitiveRequest.java

@@ -1,7 +0,0 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
-
-import java.util.List;
-
-/** Created by the ProtocolParser to allow easy access to the request contents */
-public record PrimitiveRequest(
-        RequestContext context, String command, List<Parameter> parameters) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/parser/RawRequest.java

@@ -1,5 +0,0 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
-
-import java.util.List;
-
-public record RawRequest(String command, List<Parameter> parameters) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/ProtocolParser.java

@@ -1,10 +1,12 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.tokenizer.RawToken;
-import ch.unibas.dmi.dbis.cs108.casono.server.tokenizer.Token;
-import ch.unibas.dmi.dbis.cs108.casono.server.tokenizer.TokenClassifier;
-import ch.unibas.dmi.dbis.cs108.casono.server.tokenizer.TokenType;
-import ch.unibas.dmi.dbis.cs108.casono.server.tokenizer.Tokenizer;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.RequestParameter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer.RawToken;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer.Token;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer.TokenClassifier;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer.TokenType;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer.Tokenizer;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RawRequest;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
@@ -15,7 +17,7 @@ public class ProtocolParser {
     /**
      * Parses the payload of the provided RawPacket
      *
-     * @param packet the RawPacket containing the recieved data
+     * @param payload the payload to parse and check for syntax
      * @return created PrimitiveRequest
      */
     public static RawRequest parse(String payload) {
@@ -24,7 +26,7 @@ public class ProtocolParser {
 
         Iterator<Token> iterator = tokens.iterator();
         String command = readCommand(iterator);
-        List<Parameter> parameters = readParameters(iterator);
+        List<RequestParameter> parameters = readParameters(iterator);
 
         return new RawRequest(command, parameters);
     }
@@ -50,8 +52,8 @@ public class ProtocolParser {
      * @param iterator
      * @return list containing all parsed parameters
      */
-    private static List<Parameter> readParameters(Iterator<Token> iterator) {
-        List<Parameter> parameters = new ArrayList<>();
+    private static List<RequestParameter> readParameters(Iterator<Token> iterator) {
+        List<RequestParameter> parameters = new ArrayList<>();
 
         try {
             while (iterator.hasNext()) {
@@ -65,7 +67,7 @@ public class ProtocolParser {
                 readSeperator(iterator.next());
                 String value = readValue(iterator.next());
 
-                parameters.add(new Parameter(key, value));
+                parameters.add(new RequestParameter(key, value));
             }
         } catch (NoSuchElementException e) {
             throw new ProtocolParserException("Ran out of tokens while reading parameter");

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/ProtocolParserException.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser;
 
 public class ProtocolParserException extends RuntimeException {
     public ProtocolParserException(String message) {

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/RawToken.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 /** Represents a raw (unclassified) token in the tokenizer. */
 public record RawToken(RawTokenType type, String value, int line, int column) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/RawTokenType.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 public enum RawTokenType {
     WORD,

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/State.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 import java.util.ArrayList;
 import java.util.List;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/Token.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 /** Represents a token in the tokenizer. */
 public record Token(TokenType type, String value, int line, int column) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/TokenClassifier.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 import java.util.ArrayList;
 import java.util.List;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/TokenType.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 /** Enumeration of token types used in the tokenizer. */
 public enum TokenType {

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/Tokenizer.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 import java.util.List;
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/parser/tokenizer/TokenizerException.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.tokenizer;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer;
 
 /** Exception thrown during tokenization. */
 public class TokenizerException extends RuntimeException {

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/PrimitiveRequest.java

@@ -0,0 +1,8 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.RequestParameter;
+import java.util.List;
+
+/** Created by the ProtocolParser to allow easy access to the request contents */
+public record PrimitiveRequest(
+        RequestContext context, String command, List<RequestParameter> parameters) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/RawRequest.java

@@ -0,0 +1,6 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.RequestParameter;
+import java.util.List;
+
+public record RawRequest(String command, List<RequestParameter> parameters) {}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/Request.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request;
 
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionId;
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/RequestContext.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.parser;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request;
 
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionId;
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/accessor/MissingParameterException.java

@@ -0,0 +1,26 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.accessor;
+
+/** Exception thrown when a required parameter key is not found. */
+public class MissingParameterException extends RuntimeException {
+    private final String parameterKey;
+
+    /**
+     * Creates a new exception for a missing required parameter.
+     *
+     * @param message human-readable description of the missing parameter
+     * @param parameterKey key of the parameter that could not be found
+     */
+    public MissingParameterException(String message, String parameterKey) {
+        super(message);
+        this.parameterKey = parameterKey;
+    }
+
+    /**
+     * Returns the missing parameter key.
+     *
+     * @return key of the parameter that could not be found
+     */
+    public String getParameterKey() {
+        return parameterKey;
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/accessor/ParameterParseException.java

@@ -0,0 +1,27 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.accessor;
+
+/** Exception thrown when a parameter value cannot be converted to the requested type. */
+public class ParameterParseException extends RuntimeException {
+    private final String parameterKey;
+
+    /**
+     * Creates a new parse exception with a root cause.
+     *
+     * @param message human-readable description of the parsing failure
+     * @param parameterKey key for whose value the error occured
+     * @param cause original exception thrown during parsing
+     */
+    public ParameterParseException(String message, String parameterKey, Throwable cause) {
+        super(message, cause);
+        this.parameterKey = parameterKey;
+    }
+
+    /**
+     * Returns the missing parameter key.
+     *
+     * @return key for whose value the error occured
+     */
+    public String getParameterKey() {
+        return parameterKey;
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/accessor/RequestParameterAccessor.java

@@ -0,0 +1,116 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.accessor;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.RequestParameter;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+/**
+ * Provides typed access to a request's parameters by indexing them by key.
+ *
+ * <p>Supports required and optional lookups, with optional conversion from {@link String} values to
+ * domain-specific types via parser functions.
+ */
+public class RequestParameterAccessor {
+    private final Map<String, String> index;
+
+    /**
+     * Creates an accessor
+     *
+     * @param parameters to use
+     */
+    public RequestParameterAccessor(List<RequestParameter> parameters) {
+        this.index =
+                parameters.stream()
+                        .collect(
+                                Collectors.toUnmodifiableMap(
+                                        RequestParameter::key, RequestParameter::value));
+    }
+
+    /**
+     * Returns the raw value for a required parameter key.
+     *
+     * @param key parameter key to look up
+     * @return raw parameter value
+     * @throws MissingParameterException if no parameter with the given key exists
+     */
+    public String require(String key) throws MissingParameterException {
+        String value = index.get(key);
+        if (value == null) {
+            throw new MissingParameterException(
+                    "Required parameter with key '" + key + "' is missing.", key);
+        }
+        return value;
+    }
+
+    /**
+     * Returns a parsed value for a required parameter key.
+     *
+     * @param key parameter key to look up
+     * @param parser parser used to convert the raw value
+     * @param <T> target type returned by the parser
+     * @return parsed parameter value
+     * @throws MissingParameterException if no parameter with the given key exists
+     * @throws ParameterParseException if parsing the raw value fails
+     */
+    public <T> T require(String key, ThrowingParser<T> parser)
+            throws MissingParameterException, ParameterParseException {
+        String value = require(key);
+        try {
+            return parser.parse(value);
+        } catch (Exception e) {
+            throw new ParameterParseException(
+                    "Error while parsing '" + key + "' with specified parser", key, e);
+        }
+    }
+
+    /**
+     * Returns the raw value for a parameter key or the provided default value if missing.
+     *
+     * @param key parameter key to look up
+     * @param defaultValue value returned when the key does not exist
+     * @return found parameter value or {@code defaultValue} if absent
+     */
+    public String optional(String key, String defaultValue) {
+        String value = index.get(key);
+        if (value == null) {
+            return defaultValue;
+        }
+        return value;
+    }
+
+    /**
+     * Returns a parsed value for a parameter key or the provided default value if missing.
+     *
+     * @param key parameter key to look up
+     * @param defaultValue value returned when the key does not exist
+     * @param parser parser used to convert the raw value
+     * @param <T> target type returned by the parser
+     * @return parsed parameter value or {@code defaultValue} if absent
+     * @throws ParameterParseException if parsing the raw value fails
+     */
+    public <T> T optional(String key, T defaultValue, ThrowingParser<T> parser)
+            throws ParameterParseException {
+        String value = index.get(key);
+        if (value == null) {
+            return defaultValue;
+        }
+
+        try {
+            return parser.parse(value);
+        } catch (Exception e) {
+            throw new ParameterParseException(
+                    "Error while parsing '" + key + "' with specified parser", key, e);
+        }
+    }
+
+    /**
+     * Checks whether a parameter with the given key exists.
+     *
+     * @param key parameter key to check
+     * @return {@code true} if the key exists, otherwise {@code false}
+     */
+    public boolean containsKey(String key) {
+        return index.containsKey(key);
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/request/accessor/ThrowingParser.java

@@ -0,0 +1,18 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.accessor;
+
+/**
+ * Functional parser interface used to convert a raw string parameter into a target type.
+ *
+ * @param <T> target type produced by the parser
+ */
+@FunctionalInterface
+interface ThrowingParser<T> {
+    /**
+     * Parses the provided raw parameter value.
+     *
+     * @param value raw parameter value
+     * @return parsed value
+     * @throws Exception if the value cannot be parsed
+     */
+    T parse(String value) throws Exception;
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/ErrorResponse.java

@@ -1,22 +1,20 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionId;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
 
 /** Response representing an error outcome for a client's request. */
 public class ErrorResponse extends Response {
     /**
      * Construct an error response with a code and message.
      *
-     * @param sessionId the target session id
-     * @param requestId the originating request id
+     * @param context the RequestContext of the request
      * @param errorCode a short error code identifying the failure
      * @param errorMessage a human readable error message
      */
-    public ErrorResponse(
-            SessionId sessionId, int requestId, String errorCode, String errorMessage) {
+    public ErrorResponse(RequestContext context, String errorCode, String errorMessage) {
         super(
-                sessionId,
-                requestId,
+                context,
                 ResponseBody.builder().param("CODE", errorCode).param("MSG", errorMessage).build());
     }
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/OkResponse.java

@@ -0,0 +1,20 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
+
+/**
+ * A simple success response with an empty body.
+ *
+ * <p>Use this to acknowledge successful requests that do not carry additional payload data.
+ */
+public class OkResponse extends SuccessResponse {
+    /**
+     * Create a minimal successful response (no body content).
+     *
+     * @param context the RequestContext of the request
+     */
+    public OkResponse(RequestContext context) {
+        super(context, ResponseBody.builder().build());
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/PrimitiveResponse.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response;
 
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionId;
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/Response.java

@@ -1,23 +1,22 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response;
 
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionId;
 
 /** Abstract base class for all server responses sent to clients. */
 public abstract class Response {
-    private final SessionId sessionId;
-    private final int requestId;
+    private final RequestContext context;
     private final ResponseBody body;
 
     /**
      * Create a new {@code Response}.
      *
-     * @param sessionId the id of the session this response targets
-     * @param requestId the request identifier this response corresponds to
+     * @param context the RequestContext of the request
      * @param body the structured response body
      */
-    protected Response(SessionId sessionId, int requestId, ResponseBody body) {
-        this.sessionId = sessionId;
-        this.requestId = requestId;
+    protected Response(RequestContext context, ResponseBody body) {
+        this.context = context;
         this.body = body;
     }
 
@@ -29,12 +28,12 @@ public abstract class Response {
     public abstract String prefix();
 
     /**
-     * Returns the session id that should receive this response.
+     * Returns the session id of the session that should receive this response.
      *
      * @return the target {@link SessionId}
      */
     public SessionId getSessionId() {
-        return sessionId;
+        return context.sessionId();
     }
 
     /**
@@ -43,7 +42,7 @@ public abstract class Response {
      * @return the numeric request id
      */
     public int getRequestId() {
-        return requestId;
+        return context.requestId();
     }
 
     /**

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/SuccessResponse.java

@@ -1,6 +1,7 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionId;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
 
 /**
  * Abstract {@link Response} specialization indicating a successful outcome.
@@ -12,12 +13,11 @@ public abstract class SuccessResponse extends Response {
     /**
      * Create a successful response with the provided body.
      *
-     * @param sessionId the session id this response targets
-     * @param requestId the originating request id
+     * @param context the RequestContext of the request
      * @param body the response body
      */
-    protected SuccessResponse(SessionId sessionId, int requestId, ResponseBody body) {
-        super(sessionId, requestId, body);
+    protected SuccessResponse(RequestContext context, ResponseBody body) {
+        super(context, body);
     }
 
     /**

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/builder/ResponseBlock.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder;
 
 import java.util.List;
 

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/builder/ResponseBody.java

@@ -1,5 +1,6 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder;
 
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.Response;
 import java.util.List;
 
 /**

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/builder/ResponseBodyBuilder.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder;
 
 import java.util.ArrayList;
 import java.util.List;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/builder/ResponseNode.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder;
 
 /**
  * Marker interface for elements that may appear in a {@link ResponseBody}.

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/builder/ResponseParameter.java

@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder;
 
 /**
  * A parameter node stored in a {@link ResponseBody}.

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/dispatcher/ResponseDispatchException.java

@@ -0,0 +1,7 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher;
+
+public class ResponseDispatchException extends RuntimeException {
+    public ResponseDispatchException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/dispatcher/ResponseDispatcher.java

@@ -1,5 +1,7 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher;
 
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.PrimitiveResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.Response;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.Session;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionManager;
 
@@ -25,12 +27,17 @@ public class ResponseDispatcher {
      * the target session's response queue.
      *
      * @param response the response to dispatch
-     * @throws InterruptedException if the thread is interrupted while waiting to enqueue the
-     *     primitive response
+     * @throws ResponseDispatchException wraps any exceptions that occur during dispatching, such as
+     *     the {@link InterruptedException}
      */
-    public void dispatch(Response response) throws InterruptedException {
+    public void dispatch(Response response) {
         PrimitiveResponse primitiveResponse = ResponseEncoder.encode(response);
         Session session = sessionManager.getSessionById(response.getSessionId());
+        try {
             session.getResponseQueue().put(primitiveResponse);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            throw new ResponseDispatchException("Interrupted while dispatching response", e);
+        }
     }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/protocol/response/dispatcher/ResponseEncoder.java

@@ -1,4 +1,10 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
+package ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.PrimitiveResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.Response;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBlock;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseNode;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseParameter;
 
 /**
  * Utility responsible for encoding a {@link Response} into a protocol payload string and wrapping

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/response/OkResponse.java

@@ -1,20 +0,0 @@
-package ch.unibas.dmi.dbis.cs108.casono.server.network.response;
-
-import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionId;
-
-/**
- * A simple success response with an empty body.
- *
- * <p>Use this to acknowledge successful requests that do not carry additional payload data.
- */
-public class OkResponse extends SuccessResponse {
-    /**
-     * Create a minimal successful response (no body content).
-     *
-     * @param sessionId the target session id
-     * @param requestId the originating request id
-     */
-    public OkResponse(SessionId sessionId, int requestId) {
-        super(sessionId, requestId, ResponseBody.builder().build());
-    }
-}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/Session.java

@@ -1,17 +1,18 @@
 package ch.unibas.dmi.dbis.cs108.casono.server.network.sessions;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.network.command.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.CommandParserDispatcher;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.CommandParserDispatcher;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.response.PrimitiveResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.PrimitiveResponse;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.TransportLayer;
-import java.io.IOException;
+import java.time.Instant;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
 
 /** Represents a client session in the network server. */
 public class Session {
     private final SessionId id;
+    private Instant lastActivity;
     private final TransportLayer transport;
     private final BlockingQueue<PrimitiveResponse> responseQueue;
     private final CommandParserDispatcher dispatcher;
@@ -23,7 +24,6 @@ public class Session {
      *
      * @param transport the transport layer for communication
      * @param eventBus the event bus for publishing events
-     * @throws IOException if an I/O error occurs during initialization
      */
     public Session(
             TransportLayer transport,
@@ -31,6 +31,7 @@ public class Session {
             CommandParserDispatcher dispatcher,
             CommandRouter router) {
         this.id = new SessionId();
+        this.lastActivity = Instant.now();
         this.transport = transport;
         this.dispatcher = dispatcher;
         this.router = router;
@@ -46,6 +47,20 @@ public class Session {
         return this.id;
     }
 
+    /**
+     * Gets the timestamp of the last inbound activity for this session.
+     *
+     * @return an {@link Instant} representing the time of the last inbound activity
+     */
+    public Instant getLastInboundActivity() {
+        return lastActivity;
+    }
+
+    /** Updates the timestamp of the last inbound activity for this session. */
+    public void updateLastInboundActivity() {
+        this.lastActivity = Instant.now();
+    }
+
     /**
      * Returns the TransportLayer of this session
      *

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionDisconnectJob.java

@@ -0,0 +1,40 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.sessions;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.events.DisconnectEvent;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
+import java.time.Duration;
+import java.time.Instant;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public class SessionDisconnectJob implements Runnable {
+    private final Logger logger;
+    private final SessionManager sessionManager;
+    private final EventBus eventBus;
+    private final Duration timeoutThreshold;
+
+    public SessionDisconnectJob(
+            SessionManager sessionManager, EventBus eventBus, Duration timeoutThreshold) {
+        this.logger = LogManager.getLogger(SessionDisconnectJob.class);
+        this.sessionManager = sessionManager;
+        this.eventBus = eventBus;
+        this.timeoutThreshold = timeoutThreshold;
+    }
+
+    @Override
+    public void run() {
+        logger.debug("Job started.");
+        Instant threshold = Instant.now().minus(timeoutThreshold);
+
+        for (Session session : sessionManager.getAllSessions()) {
+            if (session.getLastInboundActivity().isBefore(threshold)) {
+                eventBus.publish(new DisconnectEvent(session.getId()));
+                logger.info(
+                        "Initiated disconnect of {}, as it hasn't been active since a while",
+                        session.getId());
+            }
+        }
+
+        logger.debug("Job finished.");
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionId.java

@@ -14,7 +14,7 @@ public class SessionId {
     /**
      * Creates a new SessionId with the specified UUID.
      *
-     * @param UUID to use for this SessionId
+     * @param value UUID to use for this SessionId
      */
     public SessionId(UUID value) {
         this.value = value;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionManager.java

@@ -1,13 +1,15 @@
 package ch.unibas.dmi.dbis.cs108.casono.server.network.sessions;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.network.command.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.CommandParserDispatcher;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.DisconnectEvent;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.CommandParserDispatcher;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.TransportLayer;
 import java.io.IOException;
+import java.util.Collection;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.stream.Collectors;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -86,7 +88,7 @@ public class SessionManager {
     /**
      * Handler for the DisconnectEvent
      *
-     * @param id of the session that disconnected
+     * @param event the DisconnectEvent to handle
      */
     public void onDisconnect(DisconnectEvent event) {
         logger.debug("Recieved DisconnectEvent event for session {}", event.sessionId().value());
@@ -109,4 +111,8 @@ public class SessionManager {
 
         return handle.session();
     }
+
+    public Collection<Session> getAllSessions() {
+        return sessions.values().stream().map(SessionHandle::session).collect(Collectors.toList());
+    }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionReader.java

@@ -1,18 +1,23 @@
 package ch.unibas.dmi.dbis.cs108.casono.server.network.sessions;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.network.command.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandRouter;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.CommandParserDispatcher;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.UnknownCommandException;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.DisconnectEvent;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.CommandParserDispatcher;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.PrimitiveRequest;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.ProtocolParser;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.ProtocolParserException;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.RawRequest;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.Request;
-import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.RequestContext;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.ProtocolParser;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.ProtocolParserException;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.parser.tokenizer.TokenizerException;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.PrimitiveRequest;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RawRequest;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Request;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.ErrorResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.PrimitiveResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher.ResponseDispatchException;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher.ResponseEncoder;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.RawPacket;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.TransportLayer;
-import ch.unibas.dmi.dbis.cs108.casono.server.tokenizer.TokenizerException;
 import java.io.EOFException;
 import java.io.IOException;
 import org.apache.logging.log4j.LogManager;
@@ -41,34 +46,79 @@ public class SessionReader implements Runnable {
     public void run() {
         while (!Thread.currentThread().isInterrupted()) {
             RawPacket rawPacket = null;
+            RawRequest rawRequest = null;
+            RequestContext requestContext = null;
             try {
+                // Step 1: Read from transport
                 rawPacket = transport.read();
+                session.updateLastInboundActivity();
                 logger.debug("Recieved: {}", rawPacket);
+                requestContext = new RequestContext(session.getId(), rawPacket.requestId());
 
-                RawRequest rawRequest = ProtocolParser.parse(rawPacket.payload());
+                // Step 2: Syntax validation and conversion into transport object
+                rawRequest = ProtocolParser.parse(rawPacket.payload());
                 logger.debug("Parsed request to {}", rawRequest);
 
-                RequestContext requestContext =
-                        new RequestContext(session.getId(), rawPacket.requestId());
                 PrimitiveRequest primitiveRequest =
                         new PrimitiveRequest(
                                 requestContext, rawRequest.command(), rawRequest.parameters());
                 logger.debug("Converted to {}", primitiveRequest);
 
+                // Step 3: Parse into Request and execute Request
                 Request request = dispatcher.parse(primitiveRequest);
-
                 router.execute(request);
             } catch (EOFException e) {
                 logger.info("Client disconnected");
                 eventBus.publish(new DisconnectEvent(session.getId()));
                 break;
+
             } catch (TokenizerException | ProtocolParserException e) {
                 logger.error("Error occured while parsing request. RawPacket: {}", rawPacket, e);
 
-                // TODO: Send error response to client
+                sendErrorResponse(
+                        new ErrorResponse(
+                                requestContext,
+                                "PARSING_ERROR",
+                                "Error occured during parsing. Likely due to malformed payload."));
+
+            } catch (UnknownCommandException e) {
+                logger.error("Recieved unknown command '{}' from client", rawRequest.command(), e);
+                sendErrorResponse(
+                        new ErrorResponse(
+                                requestContext,
+                                "UNKNOWN_COMMAND",
+                                "This command is unknown to the server."));
+
+            } catch (ResponseDispatchException e) {
+                logger.error(
+                        "Unexpected ResponseDispatchException exception while dispatching request",
+                        e);
+
             } catch (IOException e) {
-                logger.error("Unexpected exception while reading from transport", e);
+                logger.error("Unexpected IO exception while reading from transport", e);
+
+            } catch (RuntimeException e) {
+                logger.error("Unexpected RuntimeException occured", e);
+                sendErrorResponse(
+                        new ErrorResponse(
+                                requestContext,
+                                "INTERNAL_ERROR",
+                                "Unexpected internal server error occured."));
             }
         }
     }
+
+    /**
+     * Helperfunction to send ErrorResponse to client
+     *
+     * @param response to send to the client
+     */
+    private void sendErrorResponse(ErrorResponse response) {
+        PrimitiveResponse primitiveResponse = ResponseEncoder.encode(response);
+        try {
+            session.getResponseQueue().put(primitiveResponse);
+        } catch (InterruptedException e) {
+            logger.error("Got interrupted while sending ErrorResponse to client.");
+        }
+    }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionWriter.java

@@ -1,6 +1,6 @@
 package ch.unibas.dmi.dbis.cs108.casono.server.network.sessions;
 
-import ch.unibas.dmi.dbis.cs108.casono.server.network.response.PrimitiveResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.PrimitiveResponse;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.RawPacket;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.TransportLayer;
 import java.io.IOException;

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/transport/TcpTransport.java

@@ -50,8 +50,8 @@ public class TcpTransport implements TransportLayer {
         int requestId = data.requestId();
         byte[] rawPayload = data.payload().getBytes(StandardCharsets.UTF_8);
 
-        out.writeInt(requestId);
         out.writeInt(rawPayload.length);
+        out.writeInt(requestId);
         out.write(rawPayload);
         out.flush();
     }