org.bytedeco.javacpp.tools

Class NativeAllocationTracer

java.lang.Object

org.bytedeco.javacpp.tools.NativeAllocationTracer

public class NativeAllocationTracer
extends Object

Tracks native memory allocation sites and provides usage statistics for debugging memory lifecycle. Captures the source code location where Pointer objects are created and monitors allocation, deallocation, and garbage collection events for each site.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	NativeAllocationTracer.Location Represents a specific location in source code identified by class, method, file, and line number.
static class	NativeAllocationTracer.Site Contains allocation statistics for a specific source code location.

Field Summary

Fields

Modifier and Type	Field and Description
private static Logger	logger
private static WeakHashMap<Pointer,NativeAllocationTracer.Location>	pointerLocations Maps for remember where each Pointer object was created
private static WeakHashMap<PhantomReference<Pointer>,NativeAllocationTracer.Location>	pointerReferenceLocations Maps phantom references to allocation sites for GC-time tracking
private static HashMap<NativeAllocationTracer.Location,NativeAllocationTracer.Site>	sites Maps source code locations to their allocation statistics

Constructor Summary

Constructors

Constructor and Description
NativeAllocationTracer()

Method Summary

Modifier and Type	Method and Description
private static NativeAllocationTracer.Location	captureCreationLocation(Class<?> createdClass) Captures the location in the source code where an instance creation occurs.
static Collection<NativeAllocationTracer.Site>	getSites() Retrieves a collection of all currently tracked allocation sites.
private static void	markPointer(Pointer pointer) Associates a Pointer with its creation location for future tracking
private static void	markReference(PhantomReference<Pointer> pointerReference, Pointer pointer) Associates a Pointer Reference with its allocation location for tracking during GC.
private static void	recordAllocation(PhantomReference<Pointer> pointerReference, long size) Records when native memory is allocated, updating total and live statistics.
private static void	recordCollection(PhantomReference<Pointer> pointerReference, long size) Records when native memory is garbage collected, updating collection statistics.
private static void	recordDeallocation(PhantomReference<Pointer> pointerReference, long size) Records when native memory is manually deallocated, updating live statistics.

Methods inherited from class java.lang.Object

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

Field Detail

logger

private static final Logger logger

sites

private static final HashMap<NativeAllocationTracer.Location,NativeAllocationTracer.Site> sites

Maps source code locations to their allocation statistics

pointerLocations

private static final WeakHashMap<Pointer,NativeAllocationTracer.Location> pointerLocations

Maps for remember where each Pointer object was created

pointerReferenceLocations

private static final WeakHashMap<PhantomReference<Pointer>,NativeAllocationTracer.Location> pointerReferenceLocations

Maps phantom references to allocation sites for GC-time tracking

Constructor Detail

NativeAllocationTracer

public NativeAllocationTracer()

Method Detail

getSites

public static Collection<NativeAllocationTracer.Site> getSites()

Retrieves a collection of all currently tracked allocation sites.

Returns:

a collection of Site objects representing the allocation statistics

markPointer

private static void markPointer(Pointer pointer)

Associates a Pointer with its creation location for future tracking

Parameters:

pointer - the Pointer object to be marked and tracked

markReference

private static void markReference(PhantomReference<Pointer> pointerReference,
                                  Pointer pointer)

Associates a Pointer Reference with its allocation location for tracking during GC. First attempts to retrieve the location from the associated Pointer, then falls back to capturing the current stack frame location if not found.

Parameters:

pointerReference - the phantom reference to be marked and tracked

pointer - the Pointer object associated with the phantom reference

recordAllocation

private static void recordAllocation(PhantomReference<Pointer> pointerReference,
                                     long size)

Records when native memory is allocated, updating total and live statistics.

Parameters:

pointerReference - the phantom reference associated with the allocation

size - the number of bytes allocated

recordDeallocation

private static void recordDeallocation(PhantomReference<Pointer> pointerReference,
                                       long size)

Records when native memory is manually deallocated, updating live statistics.

Parameters:

pointerReference - the phantom reference associated with the deallocation

size - the number of bytes deallocated

recordCollection

private static void recordCollection(PhantomReference<Pointer> pointerReference,
                                     long size)

Records when native memory is garbage collected, updating collection statistics.

Parameters:

pointerReference - the phantom reference associated with the garbage collected memory

size - the number of bytes garbage collected

captureCreationLocation

private static NativeAllocationTracer.Location captureCreationLocation(Class<?> createdClass)

Captures the location in the source code where an instance creation occurs. The method extracts the stack trace information, skipping frames related to Pointer class constructors and internal tracer calls to identify the actual call site where the object instantiation was initiated.

Parameters:

createdClass - the class of the object being created

Returns:

the Location object containing class, method, file and line information, or null if the location could not be determined