src/main/java/com/example/customer/Customer.java

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+package com.example.customer;
+
+import java.time.LocalDate;
+
+/**
+ * A customer record. This is a plain, immutable value type backed by
+ * {@link CustomerService}'s in-memory dummy data, not a JPA entity.
+ */
+public record Customer(String name, String email, String company, String status, LocalDate customerSince) {
+}

src/main/java/com/example/customer/CustomerService.java

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+package com.example.customer;
+
+import org.springframework.stereotype.Service;
+
+import java.time.LocalDate;
+import java.util.List;
+
+@Service
+public class CustomerService {
+
+    // TODO Replace with a real data source (e.g. a JPA-backed CustomerRepository) once
+    // customers are no longer dummy data.
+    private static final List<Customer> DUMMY_CUSTOMERS = List.of(
+            new Customer("Alice Johnson", "alice.johnson@example.com", "Acme Corp", "Active",
+                    LocalDate.of(2019, 3, 12)),
+            new Customer("Bob Smith", "bob.smith@example.com", "Globex Inc", "Active", LocalDate.of(2020, 7, 1)),
+            new Customer("Carla Diaz", "carla.diaz@example.com", "Initech", "Inactive", LocalDate.of(2018, 11, 23)),
+            new Customer("David Chen", "david.chen@example.com", "Umbrella Corp", "Prospect",
+                    LocalDate.of(2024, 1, 15)),
+            new Customer("Elena Petrova", "elena.petrova@example.com", "Hooli", "Active", LocalDate.of(2021, 5, 30)),
+            new Customer("Frank Müller", "frank.mueller@example.com", "Soylent Corp", "Inactive",
+                    LocalDate.of(2017, 9, 4)),
+            new Customer("Grace Kim", "grace.kim@example.com", "Stark Industries", "Active",
+                    LocalDate.of(2022, 2, 18)),
+            new Customer("Hassan Ali", "hassan.ali@example.com", "Wayne Enterprises", "Prospect",
+                    LocalDate.of(2025, 4, 9)),
+            new Customer("Ingrid Nilsson", "ingrid.nilsson@example.com", "Wonka Industries", "Active",
+                    LocalDate.of(2016, 6, 21)),
+            new Customer("Julien Moreau", "julien.moreau@example.com", "Cyberdyne Systems", "Inactive",
+                    LocalDate.of(2023, 10, 8)),
+            new Customer("Katrin Bauer", "katrin.bauer@example.com", "Massive Dynamic", "Active",
+                    LocalDate.of(2020, 12, 3)),
+            new Customer("Liam O'Connor", "liam.oconnor@example.com", "Aperture Science", "Prospect",
+                    LocalDate.of(2026, 1, 27)));
+
+    public List<Customer> list() {
+        return DUMMY_CUSTOMERS;
+    }
+}

src/main/java/com/example/customer/package-info.java

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+@NullMarked
+package com.example.customer;
+
+import org.jspecify.annotations.NullMarked;

src/main/java/com/example/customer/ui/CustomerListView.java

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+package com.example.customer.ui;
+
+import com.example.base.ui.ViewTitle;
+import com.example.customer.Customer;
+import com.example.customer.CustomerService;
+import com.vaadin.flow.component.grid.Grid;
+import com.vaadin.flow.component.orderedlayout.VerticalLayout;
+import com.vaadin.flow.router.Menu;
+import com.vaadin.flow.router.PageTitle;
+import com.vaadin.flow.router.Route;
+import jakarta.annotation.security.PermitAll;
+
+import java.time.format.DateTimeFormatter;
+import java.time.format.FormatStyle;
+
+@Route(value = "customers")
+@PageTitle("Customers")
+@Menu(order = 1, icon = "vaadin:users", title = "Customers")
+@PermitAll
+class CustomerListView extends VerticalLayout {
+
+    final Grid<Customer> customerGrid;
+
+    CustomerListView(CustomerService customerService) {
+        var dateFormatter = DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM).withLocale(getLocale());
+
+        customerGrid = new Grid<>();
+        customerGrid.setItems(customerService.list());
+        customerGrid.addColumn(Customer::name).setHeader("Name").setSortable(true);
+        customerGrid.addColumn(Customer::email).setHeader("Email").setSortable(true);
+        customerGrid.addColumn(Customer::company).setHeader("Company").setSortable(true);
+        customerGrid.addColumn(Customer::status).setHeader("Status").setSortable(true);
+        customerGrid.addColumn(customer -> dateFormatter.format(customer.customerSince()))
+                .setHeader("Customer Since")
+                .setSortable(true);
+        customerGrid.setEmptyStateText("No customers found");
+        customerGrid.setSizeFull();
+
+        setSizeFull();
+        add(new ViewTitle("Customers"), customerGrid);
+    }
+}

src/main/java/com/example/customer/ui/package-info.java

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+@NullMarked
+package com.example.customer.ui;
+
+import org.jspecify.annotations.NullMarked;

src/test/java/com/example/customer/ui/CustomerListViewTest.java

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+package com.example.customer.ui;
+
+import com.vaadin.browserless.SpringBrowserlessTest;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.security.test.context.support.WithMockUser;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.MOCK)
+@WithMockUser(roles = "USER")
+class CustomerListViewTest extends SpringBrowserlessTest {
+
+    @Test
+    void grid_shows_all_dummy_customers() {
+        var view = navigate(CustomerListView.class);
+
+        assertThat(test(view.customerGrid).size()).isEqualTo(12);
+    }
+
+    @Test
+    void grid_shows_customer_columns() {
+        var view = navigate(CustomerListView.class);
+
+        assertThat(test(view.customerGrid).getCellText(0, 0)).isEqualTo("Alice Johnson");
+        assertThat(test(view.customerGrid).getCellText(0, 1)).isEqualTo("alice.johnson@example.com");
+        assertThat(test(view.customerGrid).getCellText(0, 2)).isEqualTo("Acme Corp");
+        assertThat(test(view.customerGrid).getCellText(0, 3)).isEqualTo("Active");
+        assertThat(test(view.customerGrid).getCellText(0, 4)).isNotEmpty();
+    }
+}