refactor: restructure application using MVP architecture

app/src/main/java/ru/project/App.java

@@ -2,39 +2,46 @@ package ru.project;
 
 import com.googlecode.lanterna.gui2.MultiWindowTextGUI;
 import com.googlecode.lanterna.screen.Screen;
-import com.googlecode.lanterna.screen.TerminalScreen;
 import com.googlecode.lanterna.terminal.DefaultTerminalFactory;
-import ru.project.ui.MainMenu;
-import ru.project.ui.Navigator;
+import ru.project.model.AppState;
+import ru.project.presenter.MainPresenter;
+import ru.project.view.MainView;
 
 public final class App {
 
   private App() {}
 
-  public static void main(String[] args) throws Exception {
-    DefaultTerminalFactory factory = new DefaultTerminalFactory();
-
-    Screen screen = new TerminalScreen(factory.createTerminal());
-
-    screen.startScreen();
+  public static void main(String[] args) {
+    Screen screen = null;
 
     try {
+      DefaultTerminalFactory terminalFactory = new DefaultTerminalFactory();
+
+      screen = terminalFactory.createScreen();
+      screen.startScreen();
+
       MultiWindowTextGUI gui = new MultiWindowTextGUI(screen);
 
-      // Application state
       AppState state = new AppState();
+      MainView view = new MainView();
 
-      // Controllers
-      CollectionController collectionController = new CollectionController(state);
+      MainPresenter presenter = new MainPresenter(state, view, gui);
 
-      // Navigation
-      Navigator navigator = new Navigator(gui, collectionController);
+      presenter.start();
 
-      // Application entry point
-      gui.addWindowAndWait(new MainMenu(navigator));
+    } catch (Exception e) {
+      System.err.println("Произошла ошибка при выполнении программы:");
+      e.printStackTrace();
 
     } finally {
-      screen.stopScreen();
+      if (screen != null) {
+        try {
+          screen.stopScreen();
+        } catch (Exception e) {
+          System.err.println("Не удалось корректно завершить работу терминала:");
+          e.printStackTrace();
+        }
+      }
     }
   }
 }

app/src/main/java/ru/project/AppState.java

@@ -1,18 +0,0 @@
-package ru.project;
-
-public class AppState {
-
-  private DataCollection collection;
-
-  public DataCollection getCollection() {
-    return collection;
-  }
-
-  public void setCollection(DataCollection collection) {
-    this.collection = collection;
-  }
-
-  public boolean hasCollection() {
-    return collection != null;
-  }
-}

app/src/main/java/ru/project/CollectionController.java

@@ -1,49 +0,0 @@
-package ru.project;
-
-public class CollectionController {
-
-  private final AppState state;
-
-  public CollectionController(AppState state) {
-    this.state = state;
-  }
-
-  public void createCollection() {
-    DataCollection collection = new DataCollection();
-
-    collection.add("Charlie");
-    collection.add("Alice");
-    collection.add("Bob");
-    collection.add("Alice");
-
-    state.setCollection(collection);
-  }
-
-  public DataCollection getCollection() {
-    return state.getCollection();
-  }
-
-  public boolean hasCollection() {
-    return state.hasCollection();
-  }
-
-  public void sortCollection() {
-    if (!state.hasCollection()) {
-      return;
-    }
-
-    state.getCollection().sort();
-  }
-
-  public boolean contains(String element) {
-    return state.hasCollection() && state.getCollection().contains(element);
-  }
-
-  public int countOccurrences(String element) {
-    if (!state.hasCollection()) {
-      return 0;
-    }
-
-    return state.getCollection().count(element);
-  }
-}

app/src/main/java/ru/project/DataCollection.java

@@ -1,47 +0,0 @@
-package ru.project;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-
-public class DataCollection {
-
-  private final List<String> elements = new ArrayList<>();
-
-  public void add(String element) {
-    elements.add(element);
-  }
-
-  public void sort() {
-    Collections.sort(elements);
-  }
-
-  public boolean contains(String element) {
-    return elements.contains(element);
-  }
-
-  public int count(String element) {
-    int count = 0;
-
-    for (String current : elements) {
-      if (current.equals(element)) {
-        count++;
-      }
-    }
-
-    return count;
-  }
-
-  public List<String> getElements() {
-    return Collections.unmodifiableList(elements);
-  }
-
-  @Override
-  public String toString() {
-    if (elements.isEmpty()) {
-      return "Коллекция пуста";
-    }
-
-    return String.join(", ", elements);
-  }
-}

app/src/main/java/ru/project/model/AppState.java

@@ -0,0 +1,32 @@
+package ru.project.model;
+
+import ru.project.collection.MyLinkedList;
+import ru.project.collection.MyList;
+import ru.project.student.Student;
+
+public class AppState {
+
+  private MyList<Student> collection;
+  private String currentFilePath;
+
+  public AppState() {
+    this.collection = new MyLinkedList<>();
+    this.currentFilePath = null;
+  }
+
+  public MyList<Student> getCollection() {
+    return collection;
+  }
+
+  public void setCollection(MyList<Student> collection) {
+    this.collection = collection;
+  }
+
+  public String getCurrentFilePath() {
+    return currentFilePath;
+  }
+
+  public void setCurrentFilePath(String currentFilePath) {
+    this.currentFilePath = currentFilePath;
+  }
+}

app/src/main/java/ru/project/presenter/CollectionPresenter.java

@@ -0,0 +1,31 @@
+package ru.project.presenter;
+
+import com.googlecode.lanterna.gui2.WindowBasedTextGUI;
+import ru.project.collection.MyList;
+import ru.project.model.AppState;
+import ru.project.student.Student;
+import ru.project.view.CollectionView;
+
+public class CollectionPresenter {
+
+  private final AppState state;
+  private final CollectionView view;
+  private final WindowBasedTextGUI gui;
+
+  public CollectionPresenter(AppState state, CollectionView view, WindowBasedTextGUI gui) {
+    this.state = state;
+    this.view = view;
+    this.gui = gui;
+  }
+
+  public void start() {
+    MyList<Student> collection = state.getCollection();
+
+    if (collection == null || collection.isEmpty()) {
+      view.showEmptyMessage(gui);
+      return;
+    }
+
+    view.showCollection(gui, collection);
+  }
+}

app/src/main/java/ru/project/presenter/MainPresenter.java

@@ -0,0 +1,70 @@
+package ru.project.presenter;
+
+import com.googlecode.lanterna.gui2.WindowBasedTextGUI;
+import com.googlecode.lanterna.gui2.dialogs.MessageDialog;
+import com.googlecode.lanterna.gui2.dialogs.MessageDialogButton;
+import ru.project.model.AppState;
+import ru.project.view.CollectionView;
+import ru.project.view.MainView;
+
+public class MainPresenter {
+
+  private final AppState state;
+  private final MainView view;
+  private final WindowBasedTextGUI gui;
+  private final CollectionPresenter collectionPresenter;
+
+  public MainPresenter(AppState state, MainView view, WindowBasedTextGUI gui) {
+    this.state = state;
+    this.view = view;
+    this.gui = gui;
+    this.collectionPresenter = new CollectionPresenter(state, new CollectionView(), gui);
+  }
+
+  public void start() {
+    bindActions();
+    view.show(gui);
+  }
+
+  private void bindActions() {
+    view.setShowCollectionAction(this::showCollection);
+    view.setCreateCollectionAction(this::createCollection);
+    view.setSaveCollectionAction(this::saveCollection);
+    view.setSortCollectionAction(this::sortCollection);
+    view.setSearchCollectionAction(this::searchCollection);
+    view.setCountOccurrencesAction(this::countOccurrences);
+    view.setExitAction(this::exit);
+  }
+
+  private void showCollection() {
+    collectionPresenter.start();
+  }
+
+  private void createCollection() {
+    showMessage("Меню создания коллекции.");
+  }
+
+  private void saveCollection() {
+    showMessage("Меню сохранения коллекции.");
+  }
+
+  private void sortCollection() {
+    showMessage("Меню сортировки коллекции.");
+  }
+
+  private void searchCollection() {
+    showMessage("Меню поиска элемента.");
+  }
+
+  private void countOccurrences() {
+    showMessage("Меню подсчёта количества вхождений.");
+  }
+
+  private void exit() {
+    view.close();
+  }
+
+  private void showMessage(String message) {
+    MessageDialog.showMessageDialog(gui, "Информация", message, MessageDialogButton.OK);
+  }
+}

app/src/main/java/ru/project/ui/CollectionView.java

@@ -1,10 +0,0 @@
-package ru.project.ui;
-
-import ru.project.CollectionController;
-
-public class CollectionView extends EmptyMenu {
-
-  public CollectionView(CollectionController controller) {
-    super("Текущая коллекция");
-  }
-}

app/src/main/java/ru/project/ui/CountOccurrencesMenu.java

@@ -1,10 +0,0 @@
-package ru.project.ui;
-
-import ru.project.CollectionController;
-
-public class CountOccurrencesMenu extends EmptyMenu {
-
-  public CountOccurrencesMenu(CollectionController controller) {
-    super("Подсчёт количества вхождений");
-  }
-}

app/src/main/java/ru/project/ui/CreateCollectionMenu.java

@@ -1,10 +0,0 @@
-package ru.project.ui;
-
-import ru.project.CollectionController;
-
-public class CreateCollectionMenu extends EmptyMenu {
-
-  public CreateCollectionMenu(CollectionController controller) {
-    super("Создание новой коллекции");
-  }
-}

app/src/main/java/ru/project/ui/EmptyMenu.java

@@ -1,23 +0,0 @@
-package ru.project.ui;
-
-import com.googlecode.lanterna.gui2.BasicWindow;
-import com.googlecode.lanterna.gui2.Button;
-import com.googlecode.lanterna.gui2.Direction;
-import com.googlecode.lanterna.gui2.Label;
-import com.googlecode.lanterna.gui2.LinearLayout;
-import com.googlecode.lanterna.gui2.Panel;
-
-public abstract class EmptyMenu extends BasicWindow {
-
-  protected EmptyMenu(String title) {
-    super(title);
-
-    Panel panel = new Panel(new LinearLayout(Direction.VERTICAL));
-
-    panel.addComponent(new Label("Раздел находится в разработке"));
-
-    panel.addComponent(new Button("Назад", this::close));
-
-    setComponent(panel);
-  }
-}

app/src/main/java/ru/project/ui/MainMenu.java

@@ -1,34 +0,0 @@
-package ru.project.ui;
-
-import com.googlecode.lanterna.gui2.BasicWindow;
-import com.googlecode.lanterna.gui2.Button;
-import com.googlecode.lanterna.gui2.Direction;
-import com.googlecode.lanterna.gui2.LinearLayout;
-import com.googlecode.lanterna.gui2.Panel;
-
-public class MainMenu extends BasicWindow {
-
-  public MainMenu(Navigator navigator) {
-    super("ГЛАВНОЕ МЕНЮ");
-
-    Panel panel = new Panel(new LinearLayout(Direction.VERTICAL));
-
-    panel.addComponent(new Button("Показать текущую коллекцию", navigator::showCollectionView));
-
-    panel.addComponent(new Button("Создать новую коллекцию", navigator::showCreateCollection));
-
-    panel.addComponent(
-        new Button("Сохранить текущую коллекцию в файл", navigator::showSaveCollection));
-
-    panel.addComponent(new Button("Сортировать текущую коллекцию", navigator::showSortCollection));
-
-    panel.addComponent(new Button("Найти элемент", navigator::showSearchElement));
-
-    panel.addComponent(
-        new Button("Подсчитать количество вхождений", navigator::showCountOccurrences));
-
-    panel.addComponent(new Button("Завершить выполнение программы", this::close));
-
-    setComponent(panel);
-  }
-}

app/src/main/java/ru/project/ui/Navigator.java

@@ -1,44 +0,0 @@
-package ru.project.ui;
-
-import com.googlecode.lanterna.gui2.BasicWindow;
-import com.googlecode.lanterna.gui2.WindowBasedTextGUI;
-import ru.project.CollectionController;
-
-public class Navigator {
-
-  private final WindowBasedTextGUI gui;
-  private final CollectionController collectionController;
-
-  public Navigator(WindowBasedTextGUI gui, CollectionController collectionController) {
-    this.gui = gui;
-    this.collectionController = collectionController;
-  }
-
-  public void show(BasicWindow window) {
-    gui.addWindowAndWait(window);
-  }
-
-  public void showCollectionView() {
-    show(new CollectionView(collectionController));
-  }
-
-  public void showCreateCollection() {
-    show(new CreateCollectionMenu(collectionController));
-  }
-
-  public void showSaveCollection() {
-    show(new SaveCollectionMenu(collectionController));
-  }
-
-  public void showSortCollection() {
-    show(new SortCollectionMenu(collectionController));
-  }
-
-  public void showSearchElement() {
-    show(new SearchElementMenu(collectionController));
-  }
-
-  public void showCountOccurrences() {
-    show(new CountOccurrencesMenu(collectionController));
-  }
-}

app/src/main/java/ru/project/ui/SaveCollectionMenu.java

@@ -1,10 +0,0 @@
-package ru.project.ui;
-
-import ru.project.CollectionController;
-
-public class SaveCollectionMenu extends EmptyMenu {
-
-  public SaveCollectionMenu(CollectionController controller) {
-    super("Сохранение текущей коллекции");
-  }
-}

app/src/main/java/ru/project/ui/SearchElementMenu.java

@@ -1,10 +0,0 @@
-package ru.project.ui;
-
-import ru.project.CollectionController;
-
-public class SearchElementMenu extends EmptyMenu {
-
-  public SearchElementMenu(CollectionController controller) {
-    super("Поиск элемента");
-  }
-}

app/src/main/java/ru/project/ui/SortCollectionMenu.java

@@ -1,10 +0,0 @@
-package ru.project.ui;
-
-import ru.project.CollectionController;
-
-public class SortCollectionMenu extends EmptyMenu {
-
-  public SortCollectionMenu(CollectionController controller) {
-    super("Сортировка текущей коллекции");
-  }
-}

app/src/main/java/ru/project/view/CollectionView.java

@@ -0,0 +1,47 @@
+package ru.project.view;
+
+import com.googlecode.lanterna.gui2.BasicWindow;
+import com.googlecode.lanterna.gui2.Button;
+import com.googlecode.lanterna.gui2.Label;
+import com.googlecode.lanterna.gui2.LinearLayout;
+import com.googlecode.lanterna.gui2.Panel;
+import com.googlecode.lanterna.gui2.WindowBasedTextGUI;
+import ru.project.collection.MyList;
+import ru.project.student.Student;
+
+public class CollectionView {
+
+  public void showCollection(WindowBasedTextGUI gui, MyList<Student> collection) {
+    BasicWindow window = new BasicWindow("Текущая коллекция");
+
+    Panel panel = new Panel();
+    panel.setLayoutManager(new LinearLayout());
+
+    for (int i = 0; i < collection.size(); i++) {
+      Student student = collection.get(i);
+
+      panel.addComponent(new Label((i + 1) + ". " + student));
+    }
+
+    panel.addComponent(new Button("Вернуться", window::close));
+
+    window.setComponent(panel);
+
+    gui.addWindowAndWait(window);
+  }
+
+  public void showEmptyMessage(WindowBasedTextGUI gui) {
+    BasicWindow window = new BasicWindow("Текущая коллекция");
+
+    Panel panel = new Panel();
+    panel.setLayoutManager(new LinearLayout());
+
+    panel.addComponent(new Label("Текущая коллекция пуста."));
+
+    panel.addComponent(new Button("Вернуться", window::close));
+
+    window.setComponent(panel);
+
+    gui.addWindowAndWait(window);
+  }
+}

app/src/main/java/ru/project/view/MainView.java

@@ -0,0 +1,62 @@
+package ru.project.view;
+
+import com.googlecode.lanterna.gui2.ActionListBox;
+import com.googlecode.lanterna.gui2.BasicWindow;
+import com.googlecode.lanterna.gui2.LinearLayout;
+import com.googlecode.lanterna.gui2.Panel;
+import com.googlecode.lanterna.gui2.WindowBasedTextGUI;
+
+public class MainView {
+
+  private final BasicWindow window;
+  private final ActionListBox menu;
+
+  public MainView() {
+    window = new BasicWindow("Главное меню");
+
+    Panel panel = new Panel();
+    panel.setLayoutManager(new LinearLayout());
+
+    menu = new ActionListBox();
+
+    panel.addComponent(menu);
+
+    window.setComponent(panel);
+  }
+
+  public void setShowCollectionAction(Runnable action) {
+    menu.addItem("Показать текущую коллекцию", action);
+  }
+
+  public void setCreateCollectionAction(Runnable action) {
+    menu.addItem("Меню создания новой коллекции", action);
+  }
+
+  public void setSaveCollectionAction(Runnable action) {
+    menu.addItem("Меню сохранения текущей коллекции в файл", action);
+  }
+
+  public void setSortCollectionAction(Runnable action) {
+    menu.addItem("Меню сортировки текущей коллекции", action);
+  }
+
+  public void setSearchCollectionAction(Runnable action) {
+    menu.addItem("Меню поиска элемента в текущей коллекции", action);
+  }
+
+  public void setCountOccurrencesAction(Runnable action) {
+    menu.addItem("Меню подсчёта количества вхождений элемента", action);
+  }
+
+  public void setExitAction(Runnable action) {
+    menu.addItem("Завершить выполнение программы", action);
+  }
+
+  public void show(WindowBasedTextGUI gui) {
+    gui.addWindowAndWait(window);
+  }
+
+  public void close() {
+    window.close();
+  }
+}