A Note taking application in ~300 lines.

gradlew codion-demos-manual:runNotesDemo
notes demo

demos/manual/src/main/java/is/codion/manual/notes/NotesDemo.java

public final class NotesDemo {

  private static final List<String> CREATE_SCHEMA_STATEMENTS = asList(
          "create schema notes",
          "create table notes.note(" +
                  "id identity not null, " +
                  "note text not null, " +
                  "created timestamp default now() not null, " +
                  "updated timestamp)"
  );

  private static final DomainType DOMAIN = DomainType.domainType("notes");

  // The domain model API.
  interface Note {
    EntityType TYPE = DOMAIN.entityType("notes.note");

    Column<Long> ID = TYPE.longColumn("id");
    Column<String> NOTE = TYPE.stringColumn("note");
    Column<LocalDateTime> CREATED = TYPE.localDateTimeColumn("created");
    Column<LocalDateTime> UPDATED = TYPE.localDateTimeColumn("updated");
  }

  // The domain model implementation
  private static class Notes extends DomainModel {

    private Notes() {
      super(DOMAIN);
      add(Note.TYPE.define(
                      Note.ID.define()
                              .primaryKey(),
                      Note.NOTE.define()
                              .column()
                              .caption("Note")
                              .nullable(false),
                      Note.CREATED.define()
                              .column()
                              .caption("Created")
                              .nullable(false)
                              .updatable(false)
                              .columnHasDefaultValue(true),
                      Note.UPDATED.define()
                              .column()
                              .caption("Updated"))
              .keyGenerator(KeyGenerator.identity())
              .orderBy(OrderBy.descending(Note.CREATED))
              .caption("Notes")
              .build());
    }
  }

  private static final class NoteEditModel extends SwingEntityEditModel {

    private NoteEditModel(EntityConnectionProvider connectionProvider) {
      super(Note.TYPE, connectionProvider);
      // Set the Note.UPDATED value before we perform an update
      beforeUpdate().addConsumer(notes ->
              notes.values().forEach(note ->
                      note.put(Note.UPDATED, LocalDateTime.now())));
    }
  }

  private static final class NoteEditPanel extends EntityEditPanel {

    private NoteEditPanel(NoteEditModel editModel) {
      super(editModel);
      // CLEAR is the only standard control we require, for clearing the UI
      configureControls(config -> config.clear()
              .control(CLEAR));
    }

    @Override
    protected void initializeUI() {
      initialFocusAttribute().set(Note.NOTE);

      createTextField(Note.NOTE)
              .hint("Take note...")
              // Use the Enter key for inserting, updating
              // and deleting, depending on the edit model state
              .action(Control.command(this::insertDeleteOrUpdate));

      setLayout(Layouts.borderLayout());
      add(component(Note.NOTE).get(), BorderLayout.CENTER);
      // Add a button based on the CLEAR control
      add(new JButton(control(CLEAR).get()), BorderLayout.EAST);
    }

    private void insertDeleteOrUpdate() {
      EditableEntity entity = editModel().entity();
      if (entity.exists().not().get() && entity.isNotNull(Note.NOTE).get()) {
        // A new note with a non-empty text
        insert();
      }
      else if (entity.modified().get()) {
        if (entity.isNull(Note.NOTE).get()) {
          // An existing note with empty text
          deleteWithConfirmation();
        }
        else {
          // An existing note with a modified text
          updateWithConfirmation();
        }
      }
    }
  }

  private static final class NoteTableModel extends SwingEntityTableModel {

    private NoteTableModel(EntityConnectionProvider connectionProvider) {
      super(new NoteEditModel(connectionProvider));
      onInsert().set(OnInsert.ADD_TOP_SORTED);
    }
  }

  private static final class NoteTablePanel extends EntityTablePanel {

    private NoteTablePanel(NoteTableModel tableModel) {
      super(tableModel, config -> config
              // Exclude the Note.UPDATED attribute from the Edit popup menu since
              // the value is set automatically and shouldn't be editable via the UI.
              // Note.CREATED is excluded by default since it is not updatable.
              .editable(attributes -> attributes.remove(Note.UPDATED)));
      // Configure the table and columns
      table().model().sorter().setSortOrder(Note.CREATED, SortOrder.DESCENDING);
      table().setAutoResizeMode(JTable.AUTO_RESIZE_SUBSEQUENT_COLUMNS);
      FilterTableColumnModel<Attribute<?>> columnModel = table().columnModel();
      columnModel.column(Note.NOTE).setPreferredWidth(280);
      columnModel.column(Note.CREATED).setPreferredWidth(130);
      columnModel.column(Note.UPDATED).setPreferredWidth(130);
    }
  }

  private static final class NoteModel extends SwingEntityModel {

    private NoteModel(EntityConnectionProvider connectionProvider) {
      super(new NoteTableModel(connectionProvider));
    }
  }

  private static final class NotePanel extends EntityPanel {

    private NotePanel(NoteModel noteModel) {
      super(noteModel,
              new NoteEditPanel(noteModel.editModel()),
              new NoteTablePanel(noteModel.tableModel()), config -> config
                      // No need to include the default control buttons since
                      // we added the CLEAR control button to the edit panel
                      .includeControls(false)
                      // Replace the default edit base panel which uses a FlowLayout, in order
                      // to have the edit panel fill the horizontal width of the parent panel
                      .editBasePanel(editPanel -> Components.borderLayoutPanel()
                              .centerComponent(editPanel)
                              .build()));
    }
  }

  public static final class NotesApplicationModel extends SwingEntityApplicationModel {

    private static final Version VERSION = Version.builder().major(1).build();

    public NotesApplicationModel(EntityConnectionProvider connectionProvider) {
      super(connectionProvider, VERSION);
      NoteModel noteModel = new NoteModel(connectionProvider);
      addEntityModel(noteModel);
      // Refresh the table model to populate it
      noteModel.tableModel().refresh();
    }
  }

  public static final class NotesApplicationPanel extends EntityApplicationPanel<NotesApplicationModel> {

    public NotesApplicationPanel(NotesApplicationModel applicationModel) {
      super(applicationModel, NotesApplicationLayout::new);
    }

    @Override
    protected List<EntityPanel> createEntityPanels() {
      NoteModel noteModel = applicationModel().entityModel(Note.TYPE);

      return List.of(new NotePanel(noteModel));
    }

    // Replace the default JTabbedPane based layout,
    // since we're only displaying a single panel
    private static final class NotesApplicationLayout implements ApplicationLayout {

      private final EntityApplicationPanel<?> applicationPanel;

      private NotesApplicationLayout(EntityApplicationPanel<?> applicationPanel) {
        this.applicationPanel = applicationPanel;
      }

      @Override
      public JComponent layout() {
        return Components.borderLayoutPanel()
                // initialize() must be called to initialize the UI components
                .centerComponent(applicationPanel.entityPanel(Note.TYPE).initialize())
                .border(BorderFactory.createEmptyBorder(5, 5, 0, 5))
                .build();
      }
    }
  }

  private static final class NotesConnectionProviderFactory implements ConnectionProviderFactory {

    @Override
    public EntityConnectionProvider create(User user,
                                           DomainType domainType,
                                           String clientType,
                                           Version clientVersion) {
      Database database = new H2DatabaseFactory()
              .create("jdbc:h2:mem:h2db;DB_CLOSE_DELAY=-1");

      // Here we create the EntityConnectionProvider instance
      // manually so we can safely ignore some method parameters
      return LocalEntityConnectionProvider.builder()
              // Create the schema
              .database(createSchema(database))
              // Supply a domain model instance, if we used the domainType we'd
              // need to register the domain model in the ServiceLoader in order for
              // the framework to instantiate one for us
              .domain(new Notes())
              .clientVersion(clientVersion)
              .user(user)
              .build();
    }
  }

  private static void startApplication() {
    // Change the default horizontal alignment for temporal table columns
    FilterTableCellRenderer.TEMPORAL_HORIZONTAL_ALIGNMENT.set(SwingConstants.CENTER);
    // Make all the IntelliJ themes from Flat Look and Feel available (View -> Select Look & Feel)
    Arrays.stream(FlatAllIJThemes.INFOS)
            .forEach(LookAndFeelProvider::addLookAndFeel);

    EntityApplicationPanel.builder(NotesApplicationModel.class, NotesApplicationPanel.class)
            .frameTitle("Notes")
            .frameSize(new Dimension(600, 500))
            .applicationVersion(NotesApplicationModel.VERSION)
            // No need for a startup dialog since startup is very quick
            .displayStartupDialog(false)
            // Supply our connection provider factory from above
            .connectionProviderFactory(new NotesConnectionProviderFactory())
            // Automatically login with the H2Database super user
            .automaticLoginUser(User.user("sa"))
            .defaultLookAndFeelClassName(FlatMaterialDarkerIJTheme.class.getName())
            // Runs on the EventDispatchThread
            .start();
  }

  public static void main(String[] args) {
    startApplication();
  }

  private static Database createSchema(Database database) {
    List<String> dataStatements = asList(
            "insert into notes.note(note, created) " +
                    "values ('My first note', '2023-10-03 10:40')",
            "insert into notes.note(note, created) " +
                    "values ('My second note', '2023-10-03 12:20')",
            "insert into notes.note(note, created, updated) " +
                    "values ('My third note', '2023-10-04 08:50', '2023-10-04 08:52')",
            "insert into notes.note(note, created) " +
                    "values ('My fourth note', '2023-10-05 09:03')",
            "insert into notes.note(note, created) " +
                    "values ('My fifth note', '2023-10-05 18:30')",
            "commit"
    );
    try (Connection connection = database.createConnection(User.user("sa"));
         Statement stmt = connection.createStatement()) {
      for (String statement : CREATE_SCHEMA_STATEMENTS) {
        stmt.execute(statement);
      }
      for (String statement : dataStatements) {
        stmt.execute(statement);
      }

      return database;
    }
    catch (Exception e) {
      throw new RuntimeException(e);
    }
  }
}