Plugin Extensions Module

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type: module title: Plugin Extensions Module created: 2026-05-25 updated: 2026-05-25 tags:

• domain/metrics
• domain/ui status: mature related:
• "Metrics Module"
• "Feature Location Module"
• "Extension Points"
• "Feature Metrics View" sources:
• .raw/MetricsService.java
• .raw/ProjectMetricsService.java
• .raw/HighlighterService.java
• .raw/FeatureHighlighterService.java
• .raw/GetProjectMetrics.java
• .raw/GetFeatureMetricsForFeature.java

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Plugin Extensions Module

Package: se.isselab.HAnS.pluginExtensions

MetricsService (interface)

The primary API surface for external plugins. All methods fall into regions tagged in the source:

Feature model navigation

Method	Return	Notes
getFeatures()	List<FeatureModelFeature>	All registered features
getChildFeatures(feature)	List<FeatureModelFeature>	Direct children in model tree
getParentFeature(feature)	FeatureModelFeature	Returns file root if at top level
isRootFeature(feature)	boolean	True if parent is FeatureModelFile
getRootFeature(feature)	FeatureModelFeature	Walks up until parent is FeatureModelFile
getRootFeatures()	List<FeatureModelFeature>	All top-level features via sibling traversal

FeatureFileMapping (sync + async)

Method	Notes
getFeatureFileMappingOfFeature(map, feature)	Lookup by feature.getLPQText()
isFeatureInFeatureModel(map, feature)	Map containment check
getFeatureFileMappingBackground(feature, callback)	Spawns GetFeatureFileMappingForFeature
getAllFeatureFileMappingsBackground(callback)	Spawns GetFeatureFileMappings

LineCount (sync)

Method	Notes
getTotalFeatureLineCount(mapping)	Delegates to FeatureFileMapping.getTotalFeatureLineCount()
getFeatureLineCountInFile(mapping, location)	Uses location.getMappedPathPairMappedBy() as key

Tangling (sync + async)

Method	Notes
getTanglingMapOfFeature(map, feature)	Direct HashMap.get()
getFeatureTanglings(feature, callback)	Spawns GetTangledFeaturesForFeature
getFeatureTanglingDegreeBackground(feature, callback)	Spawns GetTanglingDegreeForFeature
getTanglingMapBackground(callback)	Spawns GetTanglingMap

Scattering (sync + async)

Method	Notes
getFeatureScattering(mapping)	Calls FeatureScattering.getScatteringDegree(mapping) directly
getFeatureScatteringBackground(feature, callback)	Spawns GetScatteringDegreeForFeature

NestingDepths (async only)

Method	Notes
getNestingDepthsBackGround(feature, callback)	Spawns GetNestingDepthsForFeature

NumberOfAnnotatedFiles (async only)

Method	Notes
getNumberOfAnnotatedFilesBackground(feature, callback)	Spawns GetNumberOfAnnotationsForFeature

FeatureLocation (sync)

Method	Notes
getFeatureLocations(mapping)	Delegates to FeatureFileMapping.getFeatureLocations()
getListOfFeatureLocationBlock(location)	Delegates to FeatureLocation.getFeatureLocations()

Metrics aggregate (async)

Method	Notes
getProjectMetricsBackground(callback)	Spawns GetProjectMetrics (all features)
getFeatureMetricsBackground(callback, feature)	Spawns GetFeatureMetricsForFeature

ProjectMetricsService (implementation)

@Service(Service.Level.PROJECT) — one instance per project, accessed via project.getService(ProjectMetricsService.class).

All async methods follow the pattern:

new BackgroundTask(project, "title", callback, [optional data]).queue();

getRootFeatures() traverses sibling PSI links (prev/next) from FeatureModelUtil.findFeatures().getFirst().

HighlighterService (interface)

Method	Notes
highlightFeatureInFeatureModel(String lpq)	Opens feature model and scrolls to feature by LPQ
highlighFeatureInFeatureModel(FeatureModelFeature)	Same, but from PSI element
openFileInProject(String path)	Opens file in editor
openFileInProject(String path, int start, int end)	Opens file and highlights line range

FeatureHighlighterService (implementation)

@Service(Service.Level.PROJECT) — thin delegate to static FileHighlighter methods.

Background task classes

GetProjectMetrics (Task.Backgroundable)

Runs in background thread:

1. FeatureLocationManager.getAllFeatureFileMappings(project) — full location scan
2. FeatureTangling.getTanglingMap(project, mappings) — tangling
3. NestingDepths.getNestingDepthMap(mappings) — nesting

Then iterates every FeatureFileMapping, computes per-feature metrics and sets them on the FeatureModelFeature:

• scatteringDegree, tanglingDegree, lineCount
• avgNestingDepth, maxNestingDepth, minNestingDepth
• numberOfAnnotatedFiles, numberOfFolderAnnotations, numberOfFileAnnotations

Constructs ProjectMetrics snapshot. On onSuccess() → callback.onComplete(metrics).

Progress indicator: fraction 0 → 1 over feature count.

GetFeatureMetricsForFeature (Task.Backgroundable)

Sequentially runs four sub-tasks inline (reusing same ProgressIndicator):

1. GetScatteringDegreeForFeature (0% → 25%)
2. GetTanglingDegreeForFeature (25% → 50%)
3. GetNestingDepthsForFeature (50% → 75%)
4. GetNumberOfAnnotationsForFeature (75% → 100%)

On onSuccess() → callback.onComplete(feature).

[!key-insight] GetFeatureMetricsForFeature calls .run(indicator) directly on sub-tasks rather than .queue() — they share the same background thread and progress indicator.

Callback interfaces

Interface	onComplete signature
MetricsCallback	(ProjectMetrics)
FeatureCallback	(FeatureModelFeature)
FeatureFileMappingCallback	(HashMap<String, FeatureFileMapping>)
TanglingMapCallback	(HashMap<FeatureModelFeature, HashSet<FeatureModelFeature>>)

Related

• Metrics Module — calculator implementations
• Feature Location Module — data model consumed by all tasks
• Extension Points — how external plugins register callbacks