Empty implementation for Done callback to stop accepting null

Currently `null` is tolerated as a callback for a number of
terminal-related operations. The introduced empty implementation `NOOP`
allows to prohibit `null` as a callback argument.

Author: ruspl-afed

terminal/bundles/org.eclipse.terminal.connector.local/src/org/eclipse/terminal/connector/local/launcher/LocalLauncherDelegate.java

@@ -77,6 +77,7 @@ public IConfigurationPanel getPanel(IConfigurationPanelContainer container) {
 	@Override
 	public void execute(Map<String, Object> properties, ITerminalService.Done done) {
 		Assert.isNotNull(properties);
+		Assert.isNotNull(done);
 
 		// Set the terminal tab title
 		String terminalTitle = getTerminalTitle(properties);

terminal/bundles/org.eclipse.terminal.connector.local/src/org/eclipse/terminal/connector/local/launcher/LocalLauncherHandler.java

@@ -23,6 +23,7 @@
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.jface.viewers.StructuredSelection;
 import org.eclipse.terminal.connector.local.activator.UIPlugin;
+import org.eclipse.terminal.view.core.ITerminalService;
 import org.eclipse.terminal.view.core.ITerminalsConnectorConstants;
 import org.eclipse.terminal.view.ui.launcher.ILauncherDelegate;
 import org.eclipse.ui.IEditorInput;
@@ -68,7 +69,7 @@ private void executeDelegate(ISelection selection, ILauncherDelegate delegate) {
 		Map<String, Object> properties = new HashMap<>();
 		properties.put(ITerminalsConnectorConstants.PROP_DELEGATE_ID, delegate.getId());
 		properties.put(ITerminalsConnectorConstants.PROP_SELECTION, selection);
-		delegate.execute(properties, null);
+		delegate.execute(properties, ITerminalService.NOOP);
 	}
 
 }

terminal/bundles/org.eclipse.terminal.connector.process/src/org/eclipse/terminal/connector/process/internal/ProcessLauncherDelegate.java

@@ -47,6 +47,7 @@ public IConfigurationPanel getPanel(IConfigurationPanelContainer container) {
 	@Override
 	public void execute(Map<String, Object> properties, ITerminalService.Done done) {
 		Assert.isNotNull(properties);
+		Assert.isNotNull(done);
 
 		// Get the terminal service
 		ITerminalService terminal = getTerminalService();

terminal/bundles/org.eclipse.terminal.connector.ssh/src/org/eclipse/terminal/connector/ssh/launcher/SshLauncherDelegate.java

@@ -55,6 +55,7 @@ public IConfigurationPanel getPanel(IConfigurationPanelContainer container) {
 	@Override
 	public void execute(Map<String, Object> properties, ITerminalService.Done done) {
 		Assert.isNotNull(properties);
+		Assert.isNotNull(done);
 
 		// Set the terminal tab title
 		String terminalTitle = getTerminalTitle(properties);

terminal/bundles/org.eclipse.terminal.connector.telnet/src/org/eclipse/terminal/connector/telnet/launcher/TelnetLauncherDelegate.java

@@ -54,6 +54,7 @@ public IConfigurationPanel getPanel(IConfigurationPanelContainer container) {
 	@Override
 	public void execute(Map<String, Object> properties, ITerminalService.Done done) {
 		Assert.isNotNull(properties);
+		Assert.isNotNull(done);
 
 		// Set the terminal tab title
 		String terminalTitle = getTerminalTitle(properties);

terminal/bundles/org.eclipse.terminal.view.core/src/org/eclipse/terminal/view/core/ITerminalService.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011 - 2018 Wind River Systems, Inc. and others. All rights reserved.
+ * Copyright (c) 2011 - 2025 Wind River Systems, Inc. and others. All rights reserved.
  * This program and the accompanying materials are made available under the terms
  * of the Eclipse Public License 2.0 which accompanies this distribution, and is
  * available at https://www.eclipse.org/legal/epl-2.0/
@@ -8,6 +8,7 @@
  *
  * Contributors:
  * Wind River Systems - initial API and implementation
+ * Alexander Fedorov (ArSysOp) - further evolution
  *******************************************************************************/
 package org.eclipse.terminal.view.core;
 
@@ -32,34 +33,48 @@ public interface Done {
 		public void done(IStatus status);
 	}
 
+	/**
+	 * Empty callback if no action is needed
+	 */
+	Done NOOP = new Done() {
+
+		@Override
+		public void done(IStatus status) {
+			//no-op
+		}
+	};
+
 	/**
 	 * Opens a terminal asynchronously and invokes the given callback if done.
 	 *
 	 * @param properties The terminal properties. Must not be <code>null</code>.
-	 * @param done The callback to invoke if finished or <code>null</code>.
+	 * @param done The callback to invoke if finished. Must not be <code>null</code>.
+	 * @see ITerminalService#NOOP
 	 */
 	public void openConsole(Map<String, Object> properties, Done done);
 
 	/**
 	 * Close the terminal asynchronously and invokes the given callback if done.
 	 *
 	 * @param properties The terminal properties. Must not be <code>null</code>.
-	 * @param done The callback to invoke if finished or <code>null</code>.
+	 * @param done The callback to invoke if finished. Must not be <code>null</code>.
+	 * @see ITerminalService#NOOP
 	 */
 	public void closeConsole(Map<String, Object> properties, Done done);
 
 	/**
 	 * Terminate (disconnect) the terminal asynchronously and invokes the given callback if done.
 	 *
 	 * @param properties The terminal properties. Must not be <code>null</code>.
-	 * @param done The callback to invoke if finished or <code>null</code>.
+	 * @param done The callback to invoke if finished. Must not be <code>null</code>.
+	 * @see ITerminalService#NOOP
 	 */
 	public void terminateConsole(Map<String, Object> properties, Done done);
 
 	/**
 	 * Register the given listener to receive notifications about terminal events.
 	 * Calling this method multiple times with the same listener has no effect.
-
+	
 	 * @param listener The terminal tab listener. Must not be <code>null</code>.
 	 */
 	public void addTerminalTabListener(ITerminalTabListener listener);

terminal/bundles/org.eclipse.terminal.view.ui/src/org/eclipse/terminal/view/ui/internal/TerminalService.java

@@ -77,7 +77,8 @@ protected static abstract class TerminalServiceRunnable {
 		 * @param title The terminal tab title. Must not be <code>null</code>.
 		 * @param connector The terminal connector. Must not be <code>null</code>.
 		 * @param data The custom terminal data node or <code>null</code>.
-		 * @param done The callback to invoke if the operation finished or <code>null</code>.
+		 * @param done The callback to invoke if finished. Must not be <code>null</code>.
+		 * @see ITerminalService#NOOP
 		 */
 		public abstract void run(TerminalViewId tvid, String title, ITerminalConnector connector, Object data,
 				Done done);
@@ -165,6 +166,7 @@ protected final void executeServiceOperation(final Map<String, Object> propertie
 			final TerminalServiceRunnable runnable, final Done done) {
 		Assert.isNotNull(properties);
 		Assert.isNotNull(runnable);
+		Assert.isNotNull(done);
 
 		// Extract the properties
 		String id = (String) properties.get(ITerminalsConnectorConstants.PROP_ID);
@@ -186,9 +188,7 @@ protected final void executeServiceOperation(final Map<String, Object> propertie
 			connector = createTerminalConnector(properties);
 		} catch (CoreException e) {
 			// Properties contain invalid connector arguments
-			if (done != null) {
-				done.done(e.getStatus());
-			}
+			done.done(e.getStatus());
 			return;
 		}
 		executeServiceOperation(runnable, new TerminalViewId(id, secondaryId), title, connector, data, done);
@@ -260,6 +260,7 @@ protected ITerminalConnector createTerminalConnector(Map<String, Object> propert
 	@Override
 	public void openConsole(final Map<String, Object> properties, final Done done) {
 		Assert.isNotNull(properties);
+		Assert.isNotNull(done);
 		final boolean restoringView = fRestoringView;
 
 		executeServiceOperation(properties, new TerminalServiceRunnable() {
@@ -317,13 +318,9 @@ public void doRun(TerminalViewId tvid, String title, ITerminalConnector connecto
 						console.setData("properties", properties); //$NON-NLS-1$
 					}
 					// Invoke the callback
-					if (done != null) {
-						done.done(Status.OK_STATUS);
-					}
+					done.done(Status.OK_STATUS);
 				} catch (CoreException e) {
-					if (done != null) {
-						done.done(e.getStatus());
-					}
+					done.done(e.getStatus());
 				}
 			}
 		}, done);
@@ -332,6 +329,7 @@ public void doRun(TerminalViewId tvid, String title, ITerminalConnector connecto
 	@Override
 	public void closeConsole(final Map<String, Object> properties, final Done done) {
 		Assert.isNotNull(properties);
+		Assert.isNotNull(done);
 
 		executeServiceOperation(properties, new TerminalServiceRunnable() {
 			@Override
@@ -349,6 +347,7 @@ public void run(TerminalViewId tvid, String title, ITerminalConnector connector,
 	@Override
 	public void terminateConsole(Map<String, Object> properties, Done done) {
 		Assert.isNotNull(properties);
+		Assert.isNotNull(done);
 
 		executeServiceOperation(properties, new TerminalServiceRunnable() {
 			@Override

terminal/bundles/org.eclipse.terminal.view.ui/src/org/eclipse/terminal/view/ui/internal/handler/LaunchTerminalCommandHandler.java

@@ -30,6 +30,7 @@
 import org.eclipse.terminal.connector.ITerminalConnector;
 import org.eclipse.terminal.view.core.IContextPropertiesConstants;
 import org.eclipse.terminal.view.core.ITerminalContextPropertiesProvider;
+import org.eclipse.terminal.view.core.ITerminalService;
 import org.eclipse.terminal.view.core.ITerminalsConnectorConstants;
 import org.eclipse.terminal.view.core.TerminalContextPropertiesProviderFactory;
 import org.eclipse.terminal.view.ui.internal.ITraceIds;
@@ -84,7 +85,8 @@ public Object execute(ExecutionEvent event) throws ExecutionException {
 				dialog.setSelection(selection);
 			}
 			if (dialog.open() == Window.OK) {
-				findDelegate(dialog).ifPresent(delegate -> delegate.execute(dialog.getSettings(), null));
+				findDelegate(dialog)
+						.ifPresent(delegate -> delegate.execute(dialog.getSettings(), ITerminalService.NOOP));
 			}
 		} else {
 			if (UIPlugin.getTraceHandler().isSlotEnabled(0, ITraceIds.TRACE_LAUNCH_TERMINAL_COMMAND_HANDLER)) {
@@ -116,7 +118,8 @@ public Object execute(ExecutionEvent event) throws ExecutionException {
 					dialog.setSelection(selection);
 				}
 				if (dialog.open() == Window.OK) {
-					findDelegate(dialog).ifPresent(delegate -> delegate.execute(dialog.getSettings(), null));
+					findDelegate(dialog)
+							.ifPresent(delegate -> delegate.execute(dialog.getSettings(), ITerminalService.NOOP));
 				}
 			} else if (delegates.size() == 1) {
 				ILauncherDelegate delegate = delegates.get(0);

terminal/bundles/org.eclipse.terminal.view.ui/src/org/eclipse/terminal/view/ui/internal/local/showin/DynamicContributionItems.java

@@ -25,6 +25,7 @@
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.swt.graphics.ImageData;
+import org.eclipse.terminal.view.core.ITerminalService;
 import org.eclipse.terminal.view.core.ITerminalsConnectorConstants;
 import org.eclipse.terminal.view.ui.IExternalExecutablesProperties;
 import org.eclipse.terminal.view.ui.internal.UIPlugin;
@@ -128,7 +129,7 @@ public void run() {
 				properties.put(ITerminalsConnectorConstants.PROP_TRANSLATE_BACKSLASHES_ON_PASTE,
 						Boolean.valueOf(translate));
 
-				delegate.execute(properties, null);
+				delegate.execute(properties, ITerminalService.NOOP);
 			}
 		};
 

terminal/bundles/org.eclipse.terminal.view.ui/src/org/eclipse/terminal/view/ui/internal/view/TerminalsViewMementoHandler.java

@@ -21,6 +21,7 @@
 import org.eclipse.core.runtime.Assert;
 import org.eclipse.swt.custom.CTabItem;
 import org.eclipse.terminal.control.ITerminalViewControl;
+import org.eclipse.terminal.view.core.ITerminalService;
 import org.eclipse.terminal.view.core.ITerminalsConnectorConstants;
 import org.eclipse.terminal.view.ui.IMementoHandler;
 import org.eclipse.terminal.view.ui.internal.UIPlugin;
@@ -186,7 +187,7 @@ protected void restoreState(final TerminalsView view, IMemento memento) {
 				delegate.map(d -> d.getAdapter(IMementoHandler.class))
 						.ifPresent(mh -> mh.restoreState(connection, properties));
 				// Restore the terminal connection
-				delegate.ifPresent(d -> d.execute(properties, null));
+				delegate.ifPresent(d -> d.execute(properties, ITerminalService.NOOP));
 			}
 		}
 	}