refactor: Move EventBusListener from BooksView to BooksPresenter

TatuLund · Nov 2, 2024 · da8e3ab · da8e3ab
1 parent 3aa2fab
commit da8e3ab
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Showing 2 changed files with 57 additions and 39 deletions.
diff --git a/vaadincreate-ui/src/main/java/org/vaadin/tatu/vaadincreate/crud/BooksPresenter.java b/vaadincreate-ui/src/main/java/org/vaadin/tatu/vaadincreate/crud/BooksPresenter.java
@@ -17,8 +17,11 @@
 import org.vaadin.tatu.vaadincreate.backend.data.Category;
 import org.vaadin.tatu.vaadincreate.backend.data.Product;
 import org.vaadin.tatu.vaadincreate.backend.data.User.Role;
+import org.vaadin.tatu.vaadincreate.crud.BooksPresenter.BooksChanged.BookChange;
 import org.vaadin.tatu.vaadincreate.eventbus.EventBus;
+import org.vaadin.tatu.vaadincreate.eventbus.EventBus.EventBusListener;
 import org.vaadin.tatu.vaadincreate.locking.LockedObjects;
+import org.vaadin.tatu.vaadincreate.locking.LockedObjects.LockingEvent;
 
 /**
  * This class provides an interface for the logical operations between the CRUD
@@ -30,7 +33,7 @@
  * data.
  */
 @SuppressWarnings("serial")
-public class BooksPresenter implements Serializable {
+public class BooksPresenter implements Serializable, EventBusListener {
 
     private BooksView view;
     private transient CompletableFuture<Void> future;
@@ -48,6 +51,7 @@ public class BooksPresenter implements Serializable {
      */
     public BooksPresenter(BooksView booksView) {
         view = booksView;
+        getEventBus().registerEventBusListener(this);
     }
 
     // This method is used to load products asynchronously.
@@ -107,6 +111,7 @@ public void requestUpdateProducts() {
      */
     public void cancelUpdateProducts() {
         unlockBook();
+        getEventBus().unregisterEventBusListener(this);
         if (future != null) {
             boolean cancelled = future.cancel(true);
             future = null;
@@ -389,6 +394,21 @@ public Product getDraft() {
         return draft;
     }
 
+    @Override
+    public void eventFired(Object event) {
+        if (event instanceof LockingEvent) {
+            var id = ((LockingEvent) event).getId();
+            view.refreshProductAsync(id);
+        }
+        if (event instanceof BooksChanged) {
+            var product = ((BooksChanged) event).getProduct();
+            if (((BooksChanged) event).getChange() != BookChange.SAVE) {
+                return;
+            }
+            view.refreshProductAsync(product);
+        }
+    }
+
     private LockedObjects getLockedBooks() {
         return LockedObjects.get();
     }

diff --git a/vaadincreate-ui/src/main/java/org/vaadin/tatu/vaadincreate/crud/BooksView.java b/vaadincreate-ui/src/main/java/org/vaadin/tatu/vaadincreate/crud/BooksView.java
@@ -14,14 +14,9 @@
 import org.vaadin.tatu.vaadincreate.backend.data.Category;
 import org.vaadin.tatu.vaadincreate.backend.data.Product;
 import org.vaadin.tatu.vaadincreate.backend.data.User.Role;
-import org.vaadin.tatu.vaadincreate.crud.BooksPresenter.BooksChanged;
-import org.vaadin.tatu.vaadincreate.crud.BooksPresenter.BooksChanged.BookChange;
 import org.vaadin.tatu.vaadincreate.crud.form.BookForm;
-import org.vaadin.tatu.vaadincreate.eventbus.EventBus;
-import org.vaadin.tatu.vaadincreate.eventbus.EventBus.EventBusListener;
 import org.vaadin.tatu.vaadincreate.i18n.HasI18N;
 import org.vaadin.tatu.vaadincreate.i18n.I18n;
-import org.vaadin.tatu.vaadincreate.locking.LockedObjects.LockingEvent;
 import org.vaadin.tatu.vaadincreate.util.Utils;
 
 import com.vaadin.data.provider.ListDataProvider;
@@ -49,8 +44,7 @@
  */
 @SuppressWarnings({ "serial", "java:S2160" })
 @RolesPermitted({ Role.USER, Role.ADMIN })
-public class BooksView extends CssLayout
-        implements View, HasI18N, EventBusListener {
+public class BooksView extends CssLayout implements View, HasI18N {
 
     public static final String VIEW_NAME = "inventory";
 
@@ -113,7 +107,6 @@ public BooksView() {
         addComponent(barAndGridLayout);
         addComponent(form);
 
-        getEventBus().registerEventBusListener(this);
         presenter.init();
     }
 
@@ -450,7 +443,6 @@ public void editProduct(Product product) {
     @Override
     public void detach() {
         super.detach();
-        getEventBus().unregisterEventBusListener(this);
         // If detach happens before completion of data fetch, cancel the fetch
         presenter.cancelUpdateProducts();
         if (getUI().getSession().getSession() == null) {
@@ -515,31 +507,41 @@ private ConfirmDialog createDiscardChangesConfirmDialog() {
         return dialog;
     }
 
-    @Override
-    public void eventFired(Object event) {
-        if (event instanceof LockingEvent) {
-            var bookEvent = (LockingEvent) event;
-            Utils.access(ui, () -> {
-                if (canPush()) {
-                    dataProvider.getItems().stream().filter(
-                            book -> book.getId().equals(bookEvent.getId()))
-                            .findFirst().ifPresent(dataProvider::refreshItem);
-                }
-            });
-        }
-        if (event instanceof BooksChanged) {
-            var bookEvent = (BooksChanged) event;
-            Utils.access(ui, () -> {
-                if (canPush() && bookEvent.getChange() == BookChange.SAVE
-                        && grid.getEdited() != bookEvent.getProduct().getId()) {
-                    logger.debug("Refreshing item ({}) {}",
-                            bookEvent.getProduct().getId(),
-                            bookEvent.getProduct().getProductName());
-                    grid.setEdited(bookEvent.getProduct());
-                    dataProvider.refreshItem(bookEvent.getProduct());
-                }
-            });
-        }
+    /**
+     * Refreshes the given product asynchronously.
+     *
+     * @param product
+     *            the product to be refreshed
+     */
+    public void refreshProductAsync(Product product) {
+        Utils.access(ui, () -> {
+            if (canPush() && grid.getEdited() != product.getId()) {
+                logger.debug("Refreshing item ({}) {}", product.getId(),
+                        product.getProductName());
+                grid.setEdited(product);
+                dataProvider.refreshItem(product);
+            }
+        });
+    }
+
+    /**
+     * Refreshes the product asynchronously by its ID. This method uses the
+     * provided UI access utility to ensure that the refresh operation is
+     * performed in a thread-safe manner. If the UI can push updates, it filters
+     * the data provider's items to find the book with the specified ID and
+     * refreshes that item.
+     *
+     * @param id
+     *            the ID of the product to refresh
+     */
+    public void refreshProductAsync(Integer id) {
+        Utils.access(ui, () -> {
+            if (canPush()) {
+                dataProvider.getItems().stream()
+                        .filter(book -> book.getId().equals(id)).findFirst()
+                        .ifPresent(dataProvider::refreshItem);
+            }
+        });
     }
 
     private boolean canPush() {
@@ -561,10 +563,6 @@ private Product refreshProduct(Product product) {
         return updatedProduct;
     }
 
-    private EventBus getEventBus() {
-        return EventBus.get();
-    }
-
     private static Logger logger = LoggerFactory.getLogger(BooksView.class);
 
 }