Feature/component garbage collection

teamapps-client/ts/modules/UiPopup.ts

@@ -22,16 +22,23 @@ import {AbstractUiComponent} from "./AbstractUiComponent";
 import {TeamAppsUiContext} from "./TeamAppsUiContext";
 import {UiComponent} from "./UiComponent";
 import {TeamAppsUiComponentRegistry} from "./TeamAppsUiComponentRegistry";
-import {UiPopupCommandHandler, UiPopupConfig} from "../generated/UiPopupConfig";
+import {UiPopup_ClosedEvent, UiPopupCommandHandler, UiPopupConfig, UiPopupEventSource} from "../generated/UiPopupConfig";
 import {parseHtml} from "./Common";
 import {executeWhenFirstDisplayed} from "./util/ExecuteWhenFirstDisplayed";
+import {TeamAppsEvent} from "./util/TeamAppsEvent";
+import {keyCodes} from "./trivial-components/TrivialCore";
 
-export class UiPopup extends AbstractUiComponent<UiPopupConfig> implements UiPopupCommandHandler {
+export class UiPopup extends AbstractUiComponent<UiPopupConfig> implements UiPopupCommandHandler, UiPopupEventSource {
+
+	public readonly onClosed: TeamAppsEvent<UiPopup_ClosedEvent> = new TeamAppsEvent();
 
 	private contentComponent: UiComponent;
 	private $main: HTMLElement;
 	private $componentWrapper: HTMLElement;
 
+	private escapeKeyListener: (e: KeyboardEvent) => void;
+	private clickOutsideListener: (e: MouseEvent) => void;
+
 	constructor(config: UiPopupConfig, context: TeamAppsUiContext) {
 		super(config, context);
 
@@ -47,6 +54,34 @@ export class UiPopup extends AbstractUiComponent<UiPopupConfig> implements UiPop
 		this.setBackgroundColor(config.backgroundColor);
 		this.setDimmingColor(config.dimmingColor);
 		this.setDimensions(config.width, config.height);
+
+		this.escapeKeyListener = (e) => {
+			if (this._config.closeOnEscape && e.keyCode === keyCodes.escape) {
+				this.closeByUser();
+			}
+		};
+		document.body.addEventListener("keydown", this.escapeKeyListener, {capture: true});
+
+		this.clickOutsideListener = (e) => {
+			if (this._config.closeOnClickOutside && e.target === this.$main) {
+				this.closeByUser();
+			}
+		};
+		this.$main.addEventListener("click", this.clickOutsideListener);
+	}
+
+	private removeEventListeners() {
+		if (this.escapeKeyListener) {
+			document.body.removeEventListener("keydown", this.escapeKeyListener, {capture: true});
+		}
+		if (this.clickOutsideListener) {
+			this.$main.removeEventListener("click", this.clickOutsideListener);
+		}
+	}
+
+	private closeByUser() {
+		this.close();
+		this.onClosed.fire({});
 	}
 
 	doGetMainElement(): HTMLElement {
@@ -112,8 +147,14 @@ export class UiPopup extends AbstractUiComponent<UiPopupConfig> implements UiPop
 	}
 
 	close(): void {
+		this.removeEventListeners();
 		this.getMainElement().remove();
 	}
+
+	public destroy(): void {
+		super.destroy();
+		this.removeEventListeners();
+	}
 }
 
 TeamAppsUiComponentRegistry.registerComponentClass("UiPopup", UiPopup);

teamapps-ui-api/src/main/dto/UiPopup.dto

@@ -35,4 +35,6 @@ class UiPopup extends UiComponent {
 	command setDimensions(int width, int height);
 
 	command close();
+
+	event closed();
 }

teamapps-ux/src/main/java/org/teamapps/config/TeamAppsConfiguration.java

@@ -170,6 +170,21 @@ public class TeamAppsConfiguration {
 	 */
 	private String navigationPathPrefix = "";
 
+	/**
+	 * If enabled, client objects (components) are only weakly referenced from the session's registry,
+	 * so components that are neither displayed (reachable from a root panel, shown window, popup, etc.)
+	 * nor referenced by application code get garbage collected during the session's lifetime.
+	 * Their client-side counterparts are destroyed automatically.
+	 * <p>
+	 * If disabled (default), components stay strongly referenced by the session until it is destroyed
+	 * (historical behavior — long-lived sessions accumulate all components ever rendered).
+	 * <p>
+	 * Note: components remain strongly reachable through listener registrations they (or their event handlers)
+	 * hold on application-scoped objects such as shared models or application-wide events. For such components
+	 * to become collectable, the application must dispose/deregister those listeners when discarding the component.
+	 */
+	private boolean clientObjectGarbageCollectionEnabled = false;
+
 	public TeamAppsConfiguration() {
 	}
 
@@ -371,4 +386,18 @@ public String getNavigationPathPrefix() {
 	public void setNavigationPathPrefix(String navigationPathPrefix) {
 		this.navigationPathPrefix = navigationPathPrefix;
 	}
+
+	/**
+	 * @see #clientObjectGarbageCollectionEnabled
+	 */
+	public boolean isClientObjectGarbageCollectionEnabled() {
+		return clientObjectGarbageCollectionEnabled;
+	}
+
+	/**
+	 * @see #clientObjectGarbageCollectionEnabled
+	 */
+	public void setClientObjectGarbageCollectionEnabled(boolean clientObjectGarbageCollectionEnabled) {
+		this.clientObjectGarbageCollectionEnabled = clientObjectGarbageCollectionEnabled;
+	}
 }

teamapps-ux/src/main/java/org/teamapps/uisession/TeamAppsSessionManager.java

@@ -116,7 +116,21 @@ public TeamAppsSessionManager(TeamAppsConfiguration config, ObjectMapper objectM
 		this.houseKeepingScheduledExecutor.scheduleAtFixedRate(
 				() -> {
 					try {
-						sessionsById.values().forEach(s -> s.getUiSession().updateStats());
+						sessionsById.values().forEach(s -> {
+							try {
+								// destroy the client-side counterparts of garbage collected client objects
+								// (also covers idle sessions, which do not trigger the opportunistic drain)
+								s.getSessionContext().drainCollectedClientObjects();
+							} catch (Exception e) {
+								LOGGER.error("Exception while draining collected client objects for session " + s.getUiSession().getSessionId() + "!", e);
+							}
+							// Note: the drain above updates the registry asynchronously within the session context,
+							// so these counts may lag behind by one housekeeping cycle. That is acceptable for statistics.
+							s.getUiSession().getStatistics().updateClientObjectCounts(
+									s.getSessionContext().getClientObjectCount(),
+									s.getSessionContext().getCollectedClientObjectsCount());
+							s.getUiSession().updateStats();
+						});
 						onStatsUpdated.fire(new SessionStatsUpdatedEventData(getAllSessions(), getClosedSessionsStatistics()));
 					} catch (Exception e) {
 						LOGGER.error("Exception while flushing stats!", e);
@@ -301,7 +315,8 @@ public SessionContext createSessionContext(UiSession uiSession, UiClientInfo uiC
 				httpSession,
 				uxServerContext,
 				new SessionIconProvider(iconProvider),
-				navigationPathPrefix, new ParameterConverterProvider()
+				navigationPathPrefix, new ParameterConverterProvider(),
+				config.isClientObjectGarbageCollectionEnabled()
 		);
 	}
 

teamapps-ux/src/main/java/org/teamapps/uisession/statistics/ImmutableUiSessionStats.java

@@ -36,6 +36,8 @@ public class ImmutableUiSessionStats implements UiSessionStats {
 	private final ImmutableCountStats queryResultStats;
 	private final ImmutableSumStats sentDataStats;
 	private final ImmutableSumStats receivedDataStats;
+	private final long clientObjectCount;
+	private final long collectedClientObjectCount;
 
 	public static class ImmutableCountStats implements CountStats {
 		private final long count;
@@ -106,7 +108,9 @@ public ImmutableUiSessionStats(long startTime, long endTime,
 								   ImmutableCountStats queryStats           ,
 								   ImmutableCountStats queryResultStats     ,
 								   ImmutableSumStats sentDataStats,
-								   ImmutableSumStats receivedDataStats
+								   ImmutableSumStats receivedDataStats,
+								   long clientObjectCount,
+								   long collectedClientObjectCount
 	) {
 		this.startTime = startTime;
 		this.endTime = endTime;
@@ -120,6 +124,8 @@ public ImmutableUiSessionStats(long startTime, long endTime,
 		this.queryResultStats = queryResultStats;
 		this.sentDataStats = sentDataStats;
 		this.receivedDataStats = receivedDataStats;
+		this.clientObjectCount = clientObjectCount;
+		this.collectedClientObjectCount = collectedClientObjectCount;
 	}
 
 	@Override
@@ -181,4 +187,14 @@ public SumStats getSentDataStats() {
 	public SumStats getReceivedDataStats() {
 		return receivedDataStats;
 	}
+
+	@Override
+	public long getClientObjectCount() {
+		return clientObjectCount;
+	}
+
+	@Override
+	public long getCollectedClientObjectCount() {
+		return collectedClientObjectCount;
+	}
 }

teamapps-ux/src/main/java/org/teamapps/uisession/statistics/RunningUiSessionStats.java

@@ -133,6 +133,9 @@ public ImmutableUiSessionStats.ImmutableSumStats toImmutable() {
 	private final RunningSumStats sentDataStats = new RunningSumStats();
 	private final RunningSumStats receivedDataStats = new RunningSumStats();
 
+	private volatile long clientObjectCount;
+	private volatile long collectedClientObjectCount;
+
 
 	public RunningUiSessionStats(long startTime, String sessionId, String name) {
 		this.startTime = startTime;
@@ -200,6 +203,21 @@ public SumStats getReceivedDataStats() {
 		return receivedDataStats;
 	}
 
+	@Override
+	public long getClientObjectCount() {
+		return clientObjectCount;
+	}
+
+	@Override
+	public long getCollectedClientObjectCount() {
+		return collectedClientObjectCount;
+	}
+
+	public void updateClientObjectCounts(long clientObjectCount, long collectedClientObjectCount) {
+		this.clientObjectCount = clientObjectCount;
+		this.collectedClientObjectCount = collectedClientObjectCount;
+	}
+
 	public void nameChanged(String name) {
 		this.name = name;
 	}
@@ -240,7 +258,9 @@ public ImmutableUiSessionStats immutableCopy() {
 				queryStats.toImmutable(),
 				queryResultStats.toImmutable(),
 				sentDataStats.toImmutable(),
-				receivedDataStats.toImmutable());
+				receivedDataStats.toImmutable(),
+				clientObjectCount,
+				collectedClientObjectCount);
 	}
 
 	public void update(long totalDataSent, long totalDataReceived) {

teamapps-ux/src/main/java/org/teamapps/uisession/statistics/UiSessionStats.java

@@ -38,4 +38,14 @@ public interface UiSessionStats {
 	SumStats getSentDataStats();
 	SumStats getReceivedDataStats();
 
+	/**
+	 * Number of client objects currently registered in the session (gauge).
+	 */
+	long getClientObjectCount();
+
+	/**
+	 * Total number of client objects garbage collected during the session's lifetime (cumulative).
+	 */
+	long getCollectedClientObjectCount();
+
 }

teamapps-ux/src/main/java/org/teamapps/ux/component/AbstractComponent.java

@@ -61,6 +61,8 @@ private enum RenderingState {
 	private final Map<String, CssStyles> stylesBySelector = new HashMap<>(0);
 	private final Map<String, Map<String, String>> attributesBySelector = new HashMap<>(0);
 
+	private boolean pinnedWhileDisplayed;
+
 	public AbstractComponent() {
 		this.sessionContext = CurrentSessionContext.get();
 		id = getClass().getSimpleName() + "-" + UUID.randomUUID().toString();
@@ -84,6 +86,30 @@ public SessionContext getSessionContext() {
 		return sessionContext;
 	}
 
+	/**
+	 * Pins this component in its session context until {@link #releaseDisplayPin()}, so it does not get garbage
+	 * collected while displayed even if the application holds no reference to it
+	 * (see {@link org.teamapps.config.TeamAppsConfiguration#setClientObjectGarbageCollectionEnabled(boolean)}).
+	 * Idempotent per display cycle: consecutive calls acquire only one pin, so a racing double-release
+	 * (e.g. a server-side close plus the client's close event) cannot steal an independent application pin.
+	 */
+	public final void pinWhileDisplayed() {
+		if (!pinnedWhileDisplayed) {
+			pinnedWhileDisplayed = true;
+			sessionContext.pinClientObject(this);
+		}
+	}
+
+	/**
+	 * Releases the pin acquired by {@link #pinWhileDisplayed()}. No-op if not pinned.
+	 */
+	protected final void releaseDisplayPin() {
+		if (pinnedWhileDisplayed) {
+			pinnedWhileDisplayed = false;
+			sessionContext.unpinClientObject(this);
+		}
+	}
+
 	@Override
 	public boolean isRendered() {
 		return renderingState == RenderingState.RENDERED;

teamapps-ux/src/main/java/org/teamapps/ux/component/chat/ChatDisplay.java

@@ -44,6 +44,10 @@ public class ChatDisplay extends AbstractComponent {
 	private Icon<?, ?> deletedMessageIcon = MaterialIcon.DELETE.withStyle(MaterialIconStyles.OUTLINE_GREY_900);
 
 	private Function<ChatMessage, Component> contextMenuProvider = null;
+	// Strong reference — displayed context menus must not get garbage collected.
+	// Deliberately retained until replaced by the next context menu or explicitly closed via closeContextMenu();
+	// a client-side dismissal does not clear it (bounded: at most one menu subtree is kept alive).
+	private Component lastContextMenuComponent;
 
 	public ChatDisplay(ChatDisplayModel model) {
 		this.model = model;
@@ -98,6 +102,7 @@ public Object handleUiQuery(UiQuery query) {
 				ChatMessage chatMessage = model.getChatMessageById(q.getChatMessageId());
 				if (chatMessage != null) {
 					Component component = contextMenuProvider.apply(chatMessage);
+					lastContextMenuComponent = component; // strong reference while the context menu is displayed
 					return component != null ? component.createUiReference() : null;
 				}
 			}
@@ -175,6 +180,7 @@ public void setContextMenuProvider(Function<ChatMessage, Component> contextMenuP
 	}
 
 	public void closeContextMenu() {
+		lastContextMenuComponent = null;
 		queueCommandIfRendered(() -> new UiChatDisplay.CloseContextMenuCommand(getId()));
 	}
 

teamapps-ux/src/main/java/org/teamapps/ux/component/infiniteitemview/InfiniteItemView.java

@@ -69,6 +69,10 @@ public class InfiniteItemView<RECORD> extends AbstractComponent {
 	private final Consumer<RecordsRemovedEvent<RECORD>> modelOnRecordDeletedListener = x -> this.refresh();
 
 	private Function<RECORD, Component> contextMenuProvider = null;
+	// Strong reference — displayed context menus must not get garbage collected.
+	// Deliberately retained until replaced by the next context menu or explicitly closed via closeContextMenu();
+	// a client-side dismissal does not clear it (bounded: at most one menu subtree is kept alive).
+	private Component lastContextMenuComponent;
 	private int lastSeenContextMenuRequestId;
 
 	private int displayedRangeStart = 0;
@@ -148,6 +152,7 @@ public void handleUiEvent(UiEvent event) {
 				RECORD record = itemCache.getRecordByClientId(e.getRecordId());
 				if (record != null && contextMenuProvider != null) {
 					Component contextMenuContent = contextMenuProvider.apply(record);
+					lastContextMenuComponent = contextMenuContent; // strong reference while the context menu is displayed
 					if (contextMenuContent != null) {
 						queueCommandIfRendered(() -> new UiInfiniteItemView.SetContextMenuContentCommand(getId(), e.getRequestId(), contextMenuContent.createUiReference()));
 					} else {
@@ -311,6 +316,7 @@ public void setContextMenuProvider(Function<RECORD, Component> contextMenuProvid
 	}
 
 	public void closeContextMenu() {
+		lastContextMenuComponent = null;
 		queueCommandIfRendered(() -> new UiInfiniteItemView.CloseContextMenuCommand(getId(), this.lastSeenContextMenuRequestId));
 	}
 

teamapps-ux/src/main/java/org/teamapps/ux/component/infiniteitemview/InfiniteItemView2.java

@@ -59,6 +59,10 @@ public class InfiniteItemView2<RECORD> extends AbstractInfiniteListComponent<REC
 	private int clientRecordIdCounter = 0;
 
 	private Function<RECORD, Component> contextMenuProvider = null;
+	// Strong reference — displayed context menus must not get garbage collected.
+	// Deliberately retained until replaced by the next context menu or explicitly closed via closeContextMenu();
+	// a client-side dismissal does not clear it (bounded: at most one menu subtree is kept alive).
+	private Component lastContextMenuComponent;
 	private int lastSeenContextMenuRequestId;
 
 	private boolean selectionEnabled;
@@ -131,6 +135,7 @@ public void handleUiEvent(UiEvent event) {
 					RECORD record = renderedRecords.getRecord(e.getRecordId());
 					if (record != null) {
 						Component contextMenuContent = contextMenuProvider.apply(record);
+						lastContextMenuComponent = contextMenuContent; // strong reference while the context menu is displayed
 						if (contextMenuContent != null) {
 							queueCommandIfRendered(() -> new UiInfiniteItemView2.SetContextMenuContentCommand(getId(), e.getRequestId(), contextMenuContent.createUiReference()));
 						} else {
@@ -186,6 +191,7 @@ public void setContextMenuProvider(Function<RECORD, Component> contextMenuProvid
 	}
 
 	public void closeContextMenu() {
+		lastContextMenuComponent = null;
 		queueCommandIfRendered(() -> new UiInfiniteItemView2.CloseContextMenuCommand(getId(), this.lastSeenContextMenuRequestId));
 	}
 

teamapps-ux/src/main/java/org/teamapps/ux/component/notification/Notification.java

@@ -90,13 +90,16 @@ public void handleUiEvent(UiEvent event) {
 			}
 			case UI_NOTIFICATION_CLOSED: {
 				this.showing = false;
+				releaseDisplayPin();
 				onClosed.fire(((UiNotification.ClosedEvent) event).getByUser());
 				break;
 			}
 		}
 	}
 
 	public void close() {
+		// server-initiated close does not fire UI_NOTIFICATION_CLOSED back, so release the pin here
+		releaseDisplayPin();
 		queueCommandIfRendered(() -> new UiNotification.CloseCommand(getId()));
 	}