org.mmtk.plan
Class TransitiveClosure

java.lang.Object
  org.mmtk.plan.TransitiveClosure

Direct Known Subclasses:

GenRCModifiedProcessor, ImmortalSpaceDriver.Closure, ObjectReferenceBuffer, RCModifiedProcessor, RCZero, TraceLocal, TraceWriteBuffer

public abstract class TransitiveClosure
extends Object

This abstract class is the fundamental mechanism for performing a transitive closure over an object graph.

Some mechanisms only operate on nodes or edges, but due to limitations of inheritance we have combined these two here.

See Also:

TraceLocal

specializedScans

private static final Class<?>[] specializedScans

Database of specialized scan classes.

specializedScan

protected final int specializedScan

The specialized scan identifier

TransitiveClosure

protected TransitiveClosure()

Constructor

TransitiveClosure

protected TransitiveClosure(int specializedScan)

Constructor

Parameters:

specializedScan - The specialized scan for this trace.

registerSpecializedScan

public static void registerSpecializedScan(int id,
                                           Class<?> specializedScanClass)

A transitive closure has been created that is designed to work with a specialized scan method. We must register it here so the specializer can return the class when queried.

Parameters:

id - The method id to register.

specializedScanClass - The class to register.

getSpecializedScanClass

public static Class<?> getSpecializedScanClass(int id)

Get the specialized scan with the given id.

processEdge

public void processEdge(ObjectReference source,
                        Address slot)

Trace an edge during GC.

Parameters:

source - The source of the reference.

slot - The location containing the object reference.

processNode

public void processNode(ObjectReference object)

Trace a node during GC.

Parameters:

object - The object to be processed.