Merge master to Beta Java 20 (#189)

* Catch and log exceptions from IJDIEventListener during event dispatch

IF IJDIEventListener.handleEvent() throws an exception during
EventDispatcher.dispatch(), the debugger breaks. Stepping, resuming,
terminating, etc. doesn't work.

This change adds a try-catch block around
IJDIEventListener.handleEvent() in EventDispatcher.dispatch(), to ensure
faulty listeners don't break the debugger.

Fixes: #172

* Disable GC for exception in ExceptionEvent until event is processed

This change disables garbage collection for
ExceptionEventImpl.fException, until the event is processed by listeners
in EventDispatcher.dispatch().

Fixes: #167

* Check if AskRecurrenceDialog was cancelled and has null result (#176)

Fixes #176

* Remove references to deprecated Navigator in Scrapbook editor

It's up for removal thus offering it makes no sense.

* Clean up duplicated code in JavaRuntime

Replace the code checking if a classpath entry is modular with the new
ClasspathEntry.isModular().

Fixes: #184

---------

Co-authored-by: Simeon Andreev <simeon.danailov.andreev@gmail.com>
Co-authored-by: Andrey Loskutov <loskutov@gmx.de>
Co-authored-by: Александър Куртаков <akurtakov@gmail.com>

org.eclipse.jdt.debug.ui/ui/org/eclipse/jdt/internal/debug/ui/JavaDebugOptionsManager.java

@@ -618,6 +618,9 @@ public boolean shouldSkipSubsequentOccurrence(JDIThread thread, IJavaExceptionBr
 		if (skip == SuspendOnRecurrenceStrategy.RECURRENCE_UNCONFIGURED) {
 			skip = new AskRecurrenceDialog(JDIDebugUIPlugin.getShell()).getAnswer();
 		}
+		if (skip == null) {
+			return false; // user didn't understand the question and cancelled dialog
+		}
 		switch (skip) {
 			case SKIP_RECURRENCES:
 				return true;

org.eclipse.jdt.debug.ui/ui/org/eclipse/jdt/internal/debug/ui/snippeteditor/JavaSnippetEditor.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2022 IBM Corporation and others.
+ * Copyright (c) 2000, 2023 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -107,7 +107,6 @@
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.ui.IEditorInput;
 import org.eclipse.ui.IEditorSite;
-import org.eclipse.ui.IPageLayout;
 import org.eclipse.ui.IPartListener2;
 import org.eclipse.ui.IViewPart;
 import org.eclipse.ui.IWorkbenchPage;
@@ -1446,14 +1445,7 @@ public void run() {
 	@Override
 	public <T> T getAdapter(Class<T> required) {
 		if (required == IShowInTargetList.class) {
-			return (T) new IShowInTargetList() {
-				@SuppressWarnings("deprecation")
-				@Override
-				public String[] getShowInTargetIds() {
-					return new String[] { JavaUI.ID_PACKAGES, IPageLayout.ID_RES_NAV };
-				}
-
-			};
+			return (T) (IShowInTargetList) () -> new String[] { JavaUI.ID_PACKAGES };
 		}
 		return super.getAdapter(required);
 	}

org.eclipse.jdt.debug/jdi/org/eclipse/jdi/internal/event/ExceptionEventImpl.java

@@ -40,6 +40,8 @@ public class ExceptionEventImpl extends LocatableEventImpl implements
 	private ObjectReferenceImpl fException;
 	/** Location of catch, or 0 if not caught. */
 	private LocationImpl fCatchLocation;
+	/** Whether garbage collection has been re-enabled for the exception. */
+	private boolean fExceptionCollectionEnabled;
 
 	/**
 	 * Creates new ExceptionEventImpl.
@@ -60,6 +62,8 @@ public static ExceptionEventImpl read(MirrorImpl target,
 		event.readThreadAndLocation(target, dataInStream);
 		event.fException = ObjectReferenceImpl.readObjectRefWithTag(target,
 				dataInStream);
+		event.fException.disableCollection();
+		event.fExceptionCollectionEnabled = false;
 		event.fCatchLocation = LocationImpl.read(target, dataInStream);
 		return event;
 	}
@@ -79,4 +83,14 @@ public Location catchLocation() {
 	public ObjectReference exception() {
 		return fException;
 	}
+
+	/**
+	 * Enables garbage collection for the exception in the event. GC for the exception is initially disabled, until the exception event is processed.
+	 */
+	public void enableExceptionGC() {
+		if (!fExceptionCollectionEnabled && fException != null) {
+			fException.enableCollection();
+			fExceptionCollectionEnabled = true;
+		}
+	}
 }

org.eclipse.jdt.debug/model/org/eclipse/jdt/internal/debug/core/EventDispatcher.java

@@ -27,6 +27,7 @@
 import org.eclipse.debug.core.DebugEvent;
 import org.eclipse.debug.core.DebugException;
 import org.eclipse.debug.core.DebugPlugin;
+import org.eclipse.jdi.internal.event.ExceptionEventImpl;
 import org.eclipse.jdt.debug.core.IJavaLineBreakpoint;
 import org.eclipse.jdt.internal.debug.core.model.JDIDebugTarget;
 
@@ -153,7 +154,13 @@ private void dispatch(EventSet eventSet) {
 					}
 				}
 				vote = true;
-				resume = listener.handleEvent(event, fTarget, !resume, eventSet) && resume;
+				try {
+					resume = listener.handleEvent(event, fTarget, !resume, eventSet) && resume;
+				} catch (Throwable t) {
+					logHandleEventError(listener, event, t);
+				} finally {
+					enableGCForExceptionEvent(event);
+				}
 				continue;
 			}
 
@@ -187,7 +194,13 @@ private void dispatch(EventSet eventSet) {
 						.get(event.request());
 				if (listener != null) {
 					vote = true;
-					resume = listener.handleEvent(event, fTarget, !resume, eventSet) && resume;
+					try {
+						resume = listener.handleEvent(event, fTarget, !resume, eventSet) && resume;
+					} catch (Throwable t) {
+						logHandleEventError(listener, event, t);
+					} finally {
+						enableGCForExceptionEvent(event);
+					}
 					continue;
 				}
 			}
@@ -411,4 +424,17 @@ private void fireEvents(EventSet set) {
 		}
 	}
 
+	private static void enableGCForExceptionEvent(Event event) {
+		if (event instanceof ExceptionEventImpl) {
+			try {
+				((ExceptionEventImpl) event).enableExceptionGC();
+			} catch (Throwable t) {
+				JDIDebugPlugin.logError("Failed to enable GC for event: " + event, t); //$NON-NLS-1$
+			}
+		}
+	}
+
+	private static void logHandleEventError(IJDIEventListener listener, Event event, Throwable t) {
+		JDIDebugPlugin.logError("Exception occurred while notifying listener: " + listener + ", with event: " + event, t); //$NON-NLS-1$ //$NON-NLS-2$
+	}
 }

org.eclipse.jdt.launching/launching/org/eclipse/jdt/launching/JavaRuntime.java

@@ -78,6 +78,7 @@
 import org.eclipse.jdt.core.IPackageFragmentRoot;
 import org.eclipse.jdt.core.JavaCore;
 import org.eclipse.jdt.core.JavaModelException;
+import org.eclipse.jdt.internal.core.ClasspathEntry;
 import org.eclipse.jdt.internal.core.JavaProject;
 import org.eclipse.jdt.internal.launching.CompositeId;
 import org.eclipse.jdt.internal.launching.DefaultEntryResolver;
@@ -1036,12 +1037,7 @@ public static boolean isModule(IClasspathEntry entry, IJavaProject proj) {
 			return false;
 		}
 
-		for (IClasspathAttribute classpathAttribute : entry.getExtraAttributes()) {
-			if (classpathAttribute.getName().equals(IClasspathAttribute.MODULE) && "true".equals(classpathAttribute.getValue())) {//$NON-NLS-1$
-				return true;
-			}
-		}
-		return false;
+		return ClasspathEntry.isModular(entry);
 
 	}