VirtualizingMatchingReferenceReaderFactory.kt

TLDR

The provided file, VirtualizingMatchingReferenceReaderFactory.kt, contains the implementation of a class named VirtualizingMatchingReferenceReaderFactory. This class is responsible for creating instances of ReferenceReader that follow references from all HeapObjects. It applies matching rules provided by referenceMatchers and creates additional virtual instance references based on the list of VirtualInstanceReferenceReaders created by virtualRefReadersFactory.

Classes

VirtualizingMatchingReferenceReaderFactory

The VirtualizingMatchingReferenceReaderFactory class creates instances of ReferenceReader that follow references from all HeapObjects. It takes in a list of ReferenceMatchers (referenceMatchers) and a factory for creating VirtualInstanceReferenceReader chains (virtualRefReadersFactory). The createFor method returns a DelegatingObjectReferenceReader that delegates the reading of references to its internal readers, such as ClassReferenceReader, ChainingInstanceReferenceReader, and ObjectArrayReferenceReader.

package shark

import shark.ChainingInstanceReferenceReader.VirtualInstanceReferenceReader

// TODO Move to shark-android once HeapAnalyzer is removed.
// TODO This should be configurable to provide your own ref readers. Maybe just
/**
 * Creates [ReferenceReader] instances that will follow references from all [HeapObject]s,
 * applying matching rules provided by [referenceMatchers], creating additional virtual instance
 * reference based on the list of [VirtualInstanceReferenceReader] created by [virtualRefReadersFactory].
 */
class VirtualizingMatchingReferenceReaderFactory(
  private val referenceMatchers: List<ReferenceMatcher>,
  private val virtualRefReadersFactory: VirtualInstanceReferenceReader.ChainFactory
  ) : ReferenceReader.Factory<HeapObject> {
  override fun createFor(heapGraph: HeapGraph): ReferenceReader<HeapObject> {
    return DelegatingObjectReferenceReader(
      classReferenceReader = ClassReferenceReader(heapGraph, referenceMatchers),
      instanceReferenceReader = ChainingInstanceReferenceReader(
        virtualRefReaders = virtualRefReadersFactory.createFor(heapGraph),
        fieldRefReader = FieldInstanceReferenceReader(heapGraph, referenceMatchers)
      ),
      objectArrayReferenceReader = ObjectArrayReferenceReader()
    )
  }
}