Class ObjectModel

java.lang.Object
com.ibm.j9ddr.vm29.j9.ObjectModel
public final class ObjectModel extends Object

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected static final GCObjectModel
    gcObjectModel
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static UDATA
    adjustSizeInBytes(UDATA sizeInBytes)
    Object size should be at least minimumConsumedSize and 8 byte aligned.
    static GCHeapRegionDescriptor
    findRegionForPointer(com.ibm.j9ddr.vm29.pointer.generated.J9JavaVMPointer javaVM, GCHeapRegionManager hrm, AbstractPointer pointer, GCHeapRegionDescriptor region)
    Returns the heap region of a pointer.
    static U32
    getAge(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the age of an object.
    static UDATA
    getClassShape(com.ibm.j9ddr.vm29.pointer.generated.J9ClassPointer clazz)
    Returns the shape of an object.
    static UDATA
    getClassShape(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the shape of an object.
    static UDATA
    getConsumedSizeInBytesWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Same as getSizeInBytesWithHeader, except it takes into account object alignment and minimum object size
    UDATA
    getConsumedSizeInSlotsWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Same as getSizeInSlotsWithHeader, except it takes into account object alignment and minimum object size
    static UDATA
    getDataSizeInBytes(com.ibm.j9ddr.vm29.pointer.generated.J9IndexableObjectPointer array)
    Returns the size of data in an indexable object, in bytes, including leaves, excluding the header.
    static VoidPointer
    getElementAddress(com.ibm.j9ddr.vm29.pointer.generated.J9IndexableObjectPointer indexableObjectPointer, int elementIndex, int elementSize)
    Returns the address of an element.
    static UDATA
    getHashcodeOffset(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
     
    static UDATA
    getHeaderSize(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the size of an object header, in bytes.
    static long
    getObjectAlignmentInBytes()
    Object size should be at least minimumConsumedSize and 8 byte aligned.
    static I32
    getObjectHashCode(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Determine the basic hash code for the specified object.
    static UDATA
    getRememberedBits(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the collector bits from object's header.
    static long
    getScanType(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
     
    static UDATA
    getSizeInBytesHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the size in bytes of a hole object.
    static UDATA
    getSizeInBytesMultiSlotHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the size, in bytes, of a multi-slot hole object.
    static UDATA
    getSizeInBytesSingleSlotHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the size, in bytes, of a single slot hole object.
    static UDATA
    getSizeInBytesWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the size of an object, in bytes, including the header.
    static UDATA
    getSizeInElements(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the size of an indexable object in elements.
    UDATA
    getSizeInSlotsWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns the size of an object, in slots, including the header.
    static UDATA
    getTotalFootprintInBytesWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Get the total footprint of an object, in bytes, including the object header and all data.
    static boolean
    hasBeenHashed(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object has been hashed, FALSE otherwise.
    static boolean
    hasBeenMoved(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object has been moved after being hashed, FALSE otherwise.
    static boolean
    isDarkMatterObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object is dark matter, FALSE otherwise.
    static boolean
    isHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object is a hole, FALSE otherwise.
    static boolean
    isIndexable(com.ibm.j9ddr.vm29.pointer.generated.J9ClassPointer clazz)
    Returns TRUE if an class is indexable, FALSE otherwise.
    static boolean
    isIndexable(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object is indexable, FALSE otherwise.
    static boolean
    isInlineContiguousArraylet(com.ibm.j9ddr.vm29.pointer.generated.J9IndexableObjectPointer arrayPtr)
     
    static boolean
    isOld(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object is old, FALSE otherwise.
    static boolean
    isPointerInHeap(com.ibm.j9ddr.vm29.pointer.generated.J9JavaVMPointer javaVM, AbstractPointer pointer)
    Returns true if a pointer is in stored in heap.
    static boolean
    isPointerInRegion(AbstractPointer pointer, GCHeapRegionDescriptor region)
    Returns true if a pointer is in stored in specified region.
    static boolean
    isRemembered(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object is remembered, FALSE otherwise.
    static boolean
    isSingleSlotHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
    Returns TRUE if an object is a single slot hole object, FALSE otherwise.
    static GCHeapRegionDescriptor
    regionForAddress(com.ibm.j9ddr.vm29.pointer.generated.J9JavaVMPointer javaVM, GCHeapRegionManager hrm, AbstractPointer pointer)
    Returns the heap region for address of a pointer.

    Methods declared in class java.lang.Object

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

  • Field Details

    • gcObjectModel

      protected static final GCObjectModel gcObjectModel

  • Method Details

    • adjustSizeInBytes

      public static UDATA adjustSizeInBytes(UDATA sizeInBytes)
      Object size should be at least minimumConsumedSize and 8 byte aligned.
      Parameters:
      sizeInBytes - Real size of an object
      Returns:
      Adjusted size

    • getObjectAlignmentInBytes

      public static long getObjectAlignmentInBytes()
      Object size should be at least minimumConsumedSize and 8 byte aligned.
      Parameters:
      sizeInBytes - Real size of an object
      Returns:
      Adjusted size

    • getClassShape

      public static UDATA getClassShape(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the shape of an object.
      Parameters:
      object - Pointer to object whose shape is required.
      Returns:
      The shape of the object
      Throws:
      CorruptDataException

    • getClassShape

      public static UDATA getClassShape(com.ibm.j9ddr.vm29.pointer.generated.J9ClassPointer clazz) throws CorruptDataException
      Returns the shape of an object.
      Parameters:
      clazz - Pointer to J9Class whose shape is required.
      Returns:
      The shape of the object
      Throws:
      CorruptDataException

    • isIndexable

      public static boolean isIndexable(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object is indexable, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object is indexable, FALSE otherwise
      Throws:
      CorruptDataException

    • isIndexable

      public static boolean isIndexable(com.ibm.j9ddr.vm29.pointer.generated.J9ClassPointer clazz) throws CorruptDataException
      Returns TRUE if an class is indexable, FALSE otherwise.
      Parameters:
      clazz - Pointer to an J9Class
      Returns:
      TRUE if an class is indexable, FALSE otherwise
      Throws:
      CorruptDataException

    • isHoleObject

      public static boolean isHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object is a hole, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object is a hole, FALSE otherwise
      Throws:
      CorruptDataException

    • isSingleSlotHoleObject

      public static boolean isSingleSlotHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object is a single slot hole object, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object is a single slot hole object, FALSE otherwise
      Throws:
      CorruptDataException

    • getSizeInBytesMultiSlotHoleObject

      public static UDATA getSizeInBytesMultiSlotHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the size, in bytes, of a multi-slot hole object.
      Parameters:
      object - Pointer to an object
      Returns:
      The size, in bytes, of a multi-slot hole object
      Throws:
      CorruptDataException

    • getSizeInBytesSingleSlotHoleObject

      public static UDATA getSizeInBytesSingleSlotHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object)
      Returns the size, in bytes, of a single slot hole object.
      Parameters:
      object - Pointer to an object
      Returns:
      The size, in bytes, of a single slot hole object

    • getSizeInBytesHoleObject

      public static UDATA getSizeInBytesHoleObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the size in bytes of a hole object.
      Parameters:
      object - Pointer to an object
      Returns:
      The size in bytes of a hole object
      Throws:
      CorruptDataException

    • isDarkMatterObject

      public static boolean isDarkMatterObject(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object is dark matter, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object is dark matter, FALSE otherwise
      Throws:
      CorruptDataException

    • getSizeInBytesWithHeader

      public static UDATA getSizeInBytesWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the size of an object, in bytes, including the header.
      Parameters:
      object - Pointer to an object
      Returns:
      The size of an object, in bytes, including the header
      Throws:
      CorruptDataException

    • getTotalFootprintInBytesWithHeader

      public static UDATA getTotalFootprintInBytesWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Get the total footprint of an object, in bytes, including the object header and all data. If the object has a discontiguous representation, this method should return the size of the root object plus the total of all the discontiguous parts of the object.
      Parameters:
      object - Pointer to an object
      Returns:
      the total size of an object, in bytes, including discontiguous parts
      Throws:
      CorruptDataException

    • getConsumedSizeInBytesWithHeader

      public static UDATA getConsumedSizeInBytesWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Same as getSizeInBytesWithHeader, except it takes into account object alignment and minimum object size
      Parameters:
      object - Pointer to an object
      Returns:
      The consumed heap size of an object, in bytes, including the header
      Throws:
      CorruptDataException

    • getSizeInSlotsWithHeader

      public UDATA getSizeInSlotsWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the size of an object, in slots, including the header.
      Parameters:
      object - Pointer to an object
      Returns:
      The size of an object, in slots, including the header
      Throws:
      CorruptDataException

    • getConsumedSizeInSlotsWithHeader

      public UDATA getConsumedSizeInSlotsWithHeader(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Same as getSizeInSlotsWithHeader, except it takes into account object alignment and minimum object size
      Parameters:
      object - Pointer to an object
      Returns:
      The consumed heap size of an object, in slots, including the header
      Throws:
      CorruptDataException

    • getAge

      public static U32 getAge(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the age of an object.
      Parameters:
      object - Pointer to an object
      Returns:
      The age of the object
      Throws:
      CorruptDataException

    • isRemembered

      public static boolean isRemembered(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object is remembered, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object is remembered, FALSE otherwise
      Throws:
      CorruptDataException

    • getRememberedBits

      public static UDATA getRememberedBits(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the collector bits from object's header.
      Parameters:
      object - Pointer to an object
      Returns:
      collector bits
      Throws:
      CorruptDataException

    • isOld

      public static boolean isOld(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object is old, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object is in the old area, FALSE otherwise
      Throws:
      CorruptDataException

    • getSizeInElements

      public static UDATA getSizeInElements(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws IllegalArgumentException, CorruptDataException
      Returns the size of an indexable object in elements.
      Parameters:
      array - Pointer to the indexable object whose size is required
      Returns:
      Size of object in elements
      Throws:
      IllegalArgumentException - if the object is not an array
      CorruptDataException

    • getScanType

      public static long getScanType(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Throws:
      CorruptDataException

    • hasBeenHashed

      public static boolean hasBeenHashed(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object has been hashed, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object has been hashed, FALSE otherwise
      Throws:
      CorruptDataException

    • hasBeenMoved

      public static boolean hasBeenMoved(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns TRUE if an object has been moved after being hashed, FALSE otherwise.
      Parameters:
      object - Pointer to an object
      Returns:
      TRUE if an object has been moved after being hashed, FALSE otherwise
      Throws:
      CorruptDataException

    • getObjectHashCode

      public static 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

    • getHashcodeOffset

      public static UDATA getHashcodeOffset(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Throws:
      CorruptDataException

    • getDataSizeInBytes

      public static UDATA getDataSizeInBytes(com.ibm.j9ddr.vm29.pointer.generated.J9IndexableObjectPointer array) throws CorruptDataException
      Returns the size of data in an indexable object, in bytes, including leaves, excluding the header.
      Parameters:
      array - pointer to the indexable object whose size is required
      Returns:
      the size of an object in bytes excluding the header
      Throws:
      CorruptDataException

    • getHeaderSize

      public static UDATA getHeaderSize(com.ibm.j9ddr.vm29.pointer.generated.J9ObjectPointer object) throws CorruptDataException
      Returns the size of an object header, in bytes.

      Parameters:
      object - Pointer to an object
      Returns:
      The size of an object header, in bytes.
      Throws:
      CorruptDataException

    • getElementAddress

      public static VoidPointer getElementAddress(com.ibm.j9ddr.vm29.pointer.generated.J9IndexableObjectPointer indexableObjectPointer, int elementIndex, int elementSize) throws CorruptDataException
      Returns the address of an element.
      Parameters:
      indexableObjectPointer - Pointer to a J9 indexable object
      elementIndex - Index of the element
      elementSize - Size of the element
      Returns:
      The address of an element.
      Throws:
      CorruptDataException

    • findRegionForPointer

      public static GCHeapRegionDescriptor findRegionForPointer(com.ibm.j9ddr.vm29.pointer.generated.J9JavaVMPointer javaVM, GCHeapRegionManager hrm, AbstractPointer pointer, GCHeapRegionDescriptor region)
      Returns the heap region of a pointer.
      Parameters:
      javaVM - J9JavaVMPointer
      hrm - The gc heap region manager
      pointer - Any abstract pointer
      region - A gc heap region descriptor
      Returns:
      The heap region descriptor of the given pointer.

    • regionForAddress

      public static GCHeapRegionDescriptor regionForAddress(com.ibm.j9ddr.vm29.pointer.generated.J9JavaVMPointer javaVM, GCHeapRegionManager hrm, AbstractPointer pointer)
      Returns the heap region for address of a pointer.
      Parameters:
      javaVM - J9JavaVMPointer
      hrm - The gc heap region manager
      pointer - Any abstract pointer
      Returns:
      The heap region descriptor for address of a pointer.

    • isPointerInRegion

      public static boolean isPointerInRegion(AbstractPointer pointer, GCHeapRegionDescriptor region)
      Returns true if a pointer is in stored in specified region.
      Parameters:
      pointer - Any abstract pointer
      region - Descriptor for a region in heap
      Returns:
      If the AbstractPointer pointer is in stored in the given region in heap.

    • isPointerInHeap

      public static boolean isPointerInHeap(com.ibm.j9ddr.vm29.pointer.generated.J9JavaVMPointer javaVM, AbstractPointer pointer)
      Returns true if a pointer is in stored in heap.
      Parameters:
      javaVM - J9JavaVMPointer
      pointer - Any abstract pointer
      Returns:
      If the AbstractPointer pointer is in stored in heap.

    • isInlineContiguousArraylet

      public static boolean isInlineContiguousArraylet(com.ibm.j9ddr.vm29.pointer.generated.J9IndexableObjectPointer arrayPtr) throws CorruptDataException
      Parameters:
      arrayPtr - array object we are checking for isInlineContiguousArraylet
      Throws:
      CorruptDataException - If there's a problem accessing the layout of the indexable object