HeapImpl

java.lang.Object
- com.oracle.svm.core.heap.Heap
- - com.oracle.svm.core.genscavenge.HeapImpl

```
public final class HeapImpl
extends Heap
```
An implementation of a card remembered set generational heap.

Constructor Summary

Constructors
Constructor and Description

HeapImpl(org.graalvm.nativeimage.hosted.Feature.FeatureAccess access)

Constructors
Constructor and Description
`HeapImpl(org.graalvm.nativeimage.hosted.Feature.FeatureAccess access)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`attachThread(org.graalvm.nativeimage.IsolateThread isolateThread)` Notifies the heap that a new thread was attached to the VM.
`org.graalvm.compiler.nodes.gc.CardTableBarrierSet`	`createBarrierSet(jdk.vm.ci.meta.MetaAccessProvider metaAccess)` Returns a suitable `BarrierSet` for the garbage collector that is used for this heap.
`void`	`detachThread(org.graalvm.nativeimage.IsolateThread isolateThread)` Notifies the heap that a thread will be detached from the VM.
`void`	`endSafepoint()` Reset the heap to the normal execution state.
`Reference<?>`	`getAndClearReferencePendingList()` Atomically get the list of pending references and clears (resets) it.
`List<Class<?>>`	`getClassList()` Return a list of all the classes in the heap.
`GC`	`getGC()`
`static HeapImpl`	`getHeapImpl()`
`static ImageHeapInfo`	`getImageHeapInfo()`
`int`	`getImageHeapOffsetInAddressSpace()` Returns the offset that the image heap should have when mapping the native image file to the address space in memory.
`ObjectHeader`	`getObjectHeader()` Get the ObjectHeader implementation that this Heap uses.
`int`	`getPreferredAddressSpaceAlignment()` Returns a multiple to which the heap address space should be aligned to at runtime.
`boolean`	`hasReferencePendingList()` Determines if the heap currently has `Reference` objects that are pending to be enqueued.
`boolean`	`isAllocationDisallowed()`
`boolean`	`isInImageHeap(Object obj)` Returns true if the given object is located in the image heap.
`boolean`	`isInImageHeap(org.graalvm.word.Pointer pointer)` Returns true if the object at the given address is located in the image heap.
`void`	`prepareForSafepoint()` Prepare the heap for a safepoint.
`void`	`registerCodeConstants(CodeInfo codeInfo)` Notify the GC that run-time compiled code has embedded references to Java heap objects.
`void`	`registerRuntimeCodeInfo(CodeInfo codeInfo)` Notify the GC that a code metadata object references Java heap objects from native-memory.
`void`	`resumeAllocation()`
`void`	`suspendAllocation()`
`boolean`	`tearDown()` Tear down the heap and release its memory.
`void`	`unregisterCodeConstants(CodeInfo info)` Notify the GC that run-time compiled code will be freed that has embedded references to Java heap objects.
`void`	`unregisterRuntimeCodeInfo(CodeInfo codeInfo)` Notify the GC that a code metadata object will be freed that references Java heap objects from native-memory.
`static boolean`	`usesImageHeapCardMarking()`
`static boolean`	`usesImageHeapChunks()`
`void`	`waitForReferencePendingList()` Blocks until the heap has pending references.
`void`	`wakeUpReferencePendingListWaiters()` Unblocks any threads in `Heap.waitForReferencePendingList()`.
`boolean`	`walkCollectedHeapObjects(ObjectVisitor visitor)` Walk all heap objects except the native image heap objects.
`boolean`	`walkImageHeapObjects(ObjectVisitor visitor)` Walk all native image heap objects.
`boolean`	`walkObjects(ObjectVisitor visitor)` Walk all the objects in the heap.

Methods inherited from class com.oracle.svm.core.heap.Heap
getHeap

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - HeapImpl
```
public HeapImpl(org.graalvm.nativeimage.hosted.Feature.FeatureAccess access)
```
- Method Detail
  - getHeapImpl
```
public static HeapImpl getHeapImpl()
```
  - getImageHeapInfo
```
public static ImageHeapInfo getImageHeapInfo()
```
  - isInImageHeap
```
public boolean isInImageHeap(Object obj)
```
    Description copied from class: Heap
    
    Returns true if the given object is located in the image heap.
    
    Specified by:
    
    isInImageHeap in class Heap
  - isInImageHeap
```
public boolean isInImageHeap(org.graalvm.word.Pointer pointer)
```
    Description copied from class: Heap
    
    Returns true if the object at the given address is located in the image heap.
    
    Specified by:
    
    isInImageHeap in class Heap
  - suspendAllocation
```
public void suspendAllocation()
```
    Specified by:
    
    suspendAllocation in class Heap
  - resumeAllocation
```
public void resumeAllocation()
```
    Specified by:
    
    resumeAllocation in class Heap
  - walkObjects
```
public boolean walkObjects(ObjectVisitor visitor)
```
    Description copied from class: Heap
    
    Walk all the objects in the heap. Must only be executed as part of a VM operation that causes a safepoint.
    
    Specified by:
    
    walkObjects in class Heap
  - tearDown
```
public boolean tearDown()
```
    Tear down the heap and release its memory.
    
    Specified by:
    
    tearDown in class Heap
  - getObjectHeader
```
public ObjectHeader getObjectHeader()
```
    Description copied from class: Heap
    
    Get the ObjectHeader implementation that this Heap uses. TODO: This is used during native image generation to put appropriate headers on Objects in the native image heap. Is there any reason to expose the whole ObjectHeader interface, since only setBootImageOnLong(0L) is used then, to get the native image object header bits? TODO: Would an "Unsigned getBootImageObjectHeaderBits()" method be sufficient?
    
    Specified by:
    
    getObjectHeader in class Heap
  - getGC
```
public GC getGC()
```
    Specified by:
    
    getGC in class Heap
  - isAllocationDisallowed
```
public boolean isAllocationDisallowed()
```
    Specified by:
    
    isAllocationDisallowed in class Heap
  - getClassList
```
public List<Class<?>> getClassList()
```
    Return a list of all the classes in the heap.
    
    Specified by:
    
    getClassList in class Heap
  - prepareForSafepoint
```
public void prepareForSafepoint()
```
    Description copied from class: Heap
    
    Prepare the heap for a safepoint.
    
    Specified by:
    
    prepareForSafepoint in class Heap
  - endSafepoint
```
public void endSafepoint()
```
    Description copied from class: Heap
    
    Reset the heap to the normal execution state.
    
    Specified by:
    
    endSafepoint in class Heap
  - attachThread
```
public void attachThread(org.graalvm.nativeimage.IsolateThread isolateThread)
```
    Description copied from class: Heap
    
    Notifies the heap that a new thread was attached to the VM. This allows to initialize heap-specific datastructures, e.g., the TLAB. This method is called for every thread except the main thread (i.e., the one that maps the image heap).
    
    Specified by:
    
    attachThread in class Heap
  - detachThread
```
public void detachThread(org.graalvm.nativeimage.IsolateThread isolateThread)
```
    Description copied from class: Heap
    
    Notifies the heap that a thread will be detached from the VM. This allows to cleanup heap-specific resources, e.g., the TLAB. This method is called for every thread except the main thread (i.e., the one that maps the image heap).
    
    Specified by:
    
    detachThread in class Heap
  - usesImageHeapChunks
```
public static boolean usesImageHeapChunks()
```
  - usesImageHeapCardMarking
```
public static boolean usesImageHeapCardMarking()
```
  - getPreferredAddressSpaceAlignment
```
public int getPreferredAddressSpaceAlignment()
```
    Description copied from class: Heap
    
    Returns a multiple to which the heap address space should be aligned to at runtime.
    
    Specified by:
    
    getPreferredAddressSpaceAlignment in class Heap
    
    See Also:
    
    CommittedMemoryProvider.guaranteesHeapPreferredAddressSpaceAlignment()
  - getImageHeapOffsetInAddressSpace
```
public int getImageHeapOffsetInAddressSpace()
```
    Description copied from class: Heap
    
    Returns the offset that the image heap should have when mapping the native image file to the address space in memory.
    
    Specified by:
    
    getImageHeapOffsetInAddressSpace in class Heap
  - walkImageHeapObjects
```
public boolean walkImageHeapObjects(ObjectVisitor visitor)
```
    Description copied from class: Heap
    
    Walk all native image heap objects. Must only be executed as part of a VM operation that causes a safepoint.
    
    Specified by:
    
    walkImageHeapObjects in class Heap
  - walkCollectedHeapObjects
```
public boolean walkCollectedHeapObjects(ObjectVisitor visitor)
```
    Description copied from class: Heap
    
    Walk all heap objects except the native image heap objects. Must only be executed as part of a VM operation that causes a safepoint.
    
    Specified by:
    
    walkCollectedHeapObjects in class Heap
  - createBarrierSet
```
public org.graalvm.compiler.nodes.gc.CardTableBarrierSet createBarrierSet(jdk.vm.ci.meta.MetaAccessProvider metaAccess)
```
    Description copied from class: Heap
    
    Returns a suitable BarrierSet for the garbage collector that is used for this heap.
    
    Specified by:
    
    createBarrierSet in class Heap
  - hasReferencePendingList
```
public boolean hasReferencePendingList()
```
    Description copied from class: Heap
    
    Determines if the heap currently has Reference objects that are pending to be enqueued.
    
    Specified by:
    
    hasReferencePendingList in class Heap
  - waitForReferencePendingList
```
public void waitForReferencePendingList()
                                 throws InterruptedException
```
    Description copied from class: Heap
    
    Blocks until the heap has pending references.
    
    Specified by:
    
    waitForReferencePendingList in class Heap
    
    Throws:
    
    InterruptedException
  - wakeUpReferencePendingListWaiters
```
public void wakeUpReferencePendingListWaiters()
```
    Description copied from class: Heap
    
    Unblocks any threads in Heap.waitForReferencePendingList().
    
    Specified by:
    
    wakeUpReferencePendingListWaiters in class Heap
  - getAndClearReferencePendingList
```
public Reference<?> getAndClearReferencePendingList()
```
    Description copied from class: Heap
    
    Atomically get the list of pending references and clears (resets) it. May return null.
    
    Specified by:
    
    getAndClearReferencePendingList in class Heap
  - registerRuntimeCodeInfo
```
public void registerRuntimeCodeInfo(CodeInfo codeInfo)
```
    Description copied from class: Heap
    
    Notify the GC that a code metadata object references Java heap objects from native-memory.
    
    Specified by:
    
    registerRuntimeCodeInfo in class Heap
  - registerCodeConstants
```
public void registerCodeConstants(CodeInfo codeInfo)
```
    Description copied from class: Heap
    
    Notify the GC that run-time compiled code has embedded references to Java heap objects.
    
    Specified by:
    
    registerCodeConstants in class Heap
  - unregisterCodeConstants
```
public void unregisterCodeConstants(CodeInfo info)
```
    Description copied from class: Heap
    
    Notify the GC that run-time compiled code will be freed that has embedded references to Java heap objects.
    
    Specified by:
    
    unregisterCodeConstants in class Heap
  - unregisterRuntimeCodeInfo
```
public void unregisterRuntimeCodeInfo(CodeInfo codeInfo)
```
    Description copied from class: Heap
    
    Notify the GC that a code metadata object will be freed that references Java heap objects from native-memory.
    
    Specified by:
    
    unregisterRuntimeCodeInfo in class Heap

Class HeapImpl

Constructor Summary

Method Summary

Methods inherited from class com.oracle.svm.core.heap.Heap

Methods inherited from class java.lang.Object

Constructor Detail

HeapImpl

Method Detail

getHeapImpl

getImageHeapInfo

isInImageHeap

isInImageHeap

suspendAllocation

resumeAllocation

walkObjects

tearDown

getObjectHeader

getGC

isAllocationDisallowed

getClassList

prepareForSafepoint

endSafepoint

attachThread

detachThread

usesImageHeapChunks

usesImageHeapCardMarking

getPreferredAddressSpaceAlignment

getImageHeapOffsetInAddressSpace

walkImageHeapObjects

walkCollectedHeapObjects

createBarrierSet

hasReferencePendingList

waitForReferencePendingList

wakeUpReferencePendingListWaiters

getAndClearReferencePendingList

registerRuntimeCodeInfo

registerCodeConstants

unregisterCodeConstants

unregisterRuntimeCodeInfo