Module openj9.dtfj

Package com.ibm.j9ddr.vm29.j9.gc

Class MMObjectAccessBarrier

java.lang.Object

com.ibm.j9ddr.vm29.j9.gc.GCBase

com.ibm.j9ddr.vm29.j9.gc.MMObjectAccessBarrier

public abstract class MMObjectAccessBarrier
extends GCBase

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	MMObjectAccessBarrier()

Method Summary

Modifier and Type	Method	Description
abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer	convertPointerFromToken(long token)	Converts token (e.g. compressed pointer value) into real heap pointer.
abstract long	convertTokenFromPointer(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer pointer)	Converts real heap pointer into token (e.g. compressed pointer value).
static MMObjectAccessBarrier	from()	Factory method to construct an appropriate object model.
abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer	getFinalizeLink(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)	Fetch the finalize link field of object.
abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectMonitorPointer	getLockword(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)	Return the lockword for the given object, or NULL if it does not have a lockword.
abstract ObjectMonitor	getMonitor(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)	Return an object representing the monitor for the given object, or NULL if it does not have a lockword/monitor.
abstract I32	getObjectHashCode(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)	Determine the basic hash code for the specified object.
abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer	getReferenceLink(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)	Fetch the reference link field of the specified reference object.

Methods declared in class com.ibm.j9ddr.vm29.j9.gc.GCBase

getExtensions, getJavaVM

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MMObjectAccessBarrier

protected MMObjectAccessBarrier()

Method Detail

from

public static MMObjectAccessBarrier from()
                                  throws CorruptDataException

Factory method to construct an appropriate object model.

Parameters:

structure - the J9JavaVM structure to use

Returns:

an instance of ObjectModel

Throws:

CorruptDataException

getObjectHashCode

public abstract I32 getObjectHashCode(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
                               throws CorruptDataException

Determine the basic hash code for the specified object.

Parameters:

object - [in] the object to be hashed

Returns:

the persistent, basic hash code for the object

Throws:

CorruptDataException

getFinalizeLink

public abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer getFinalizeLink(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
                                                                              throws CorruptDataException

Fetch the finalize link field of object.

Parameters:

object - [in] the object to read

Returns:

the value stored in the object's finalizeLink field

Throws:

CorruptDataException

getReferenceLink

public abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer getReferenceLink(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
                                                                               throws CorruptDataException

Fetch the reference link field of the specified reference object.

Parameters:

object - the object to read

Returns:

the value stored in the object's reference link field

Throws:

CorruptDataException

getLockword

public abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectMonitorPointer getLockword(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
                                                                                 throws CorruptDataException

Return the lockword for the given object, or NULL if it does not have a lockword. This may return NULL, a flatlock, or an inflated monitor.

Throws:

CorruptDataException

getMonitor

public abstract ObjectMonitor getMonitor(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
                                  throws CorruptDataException

Return an object representing the monitor for the given object, or NULL if it does not have a lockword/monitor.

Throws:

CorruptDataException

convertPointerFromToken

public abstract com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer convertPointerFromToken(long token)

Converts token (e.g. compressed pointer value) into real heap pointer.

Returns:

the heap pointer value.

convertTokenFromPointer

public abstract long convertTokenFromPointer(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer pointer)

Converts real heap pointer into token (e.g. compressed pointer value).

Returns:

the compressed pointer value.