Bug 43766 [reconciling] ResourceMarkerAnnotationModel listener taking a long time
Build: I20030925 I was investigating a situation where adding breakpoints to a large file was very slow. It can take up to a second to add a breakpoint to a file such as Workspace.java (2000 lines). Almost all of this time is in the resource change listener added by ResourceMarkerAnnotationModel. First, a minor issue: Instead of adding a resource change listener that traverses the entire delta, you can locate a given resource delta within the resource change delta very quickly using IResourceDelta.findMember(): public void resourceChanged(IResourceChangeEvent e) { IResourceDelta delta= e.getDelta(); if (delta != null) { IResourceDelta child = delta.findMember(fResource.getFullPath()); if (child != null) update(child.getMarkerDeltas()); } } However, this was only a small speed improvement. The main problem is that the entire compilation unit is reparsed every time a breakpoint is added. I have added a profiler trace of where the time is going for adding a single breakpoint.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/filebuffers/CompilationUnitDocumentProvider2.java
return fOverlaids.iterator();
				return null;
			}
			
			public String getAnnotationType() {
				return fType;
			}
			/*
			 * @see IAnnotationExtension#getMarkerType()
			 */
			public String getMarkerType() {
				if (isProblem() || INFO_ANNOTATION_TYPE.equals(fType))
					return IMarker.PROBLEM;
				else
					return IMarker.TASK;
			}
			/*
			 * @see IAnnotationExtension#getSeverity()
			 */
			public int getSeverity() {
				if (ERROR_ANNOTATION_TYPE.equals(fType))
					return IMarker.SEVERITY_ERROR;
				if (WARNING_ANNOTATION_TYPE.equals(fType))
					return IMarker.SEVERITY_WARNING;
				return IMarker.SEVERITY_INFO;
			}
			/*
			 * @see org.eclipse.jdt.internal.ui.javaeditor.IJavaAnnotation#getCompilationUnit()
			 */
			public ICompilationUnit getCompilationUnit() {