Package io.github.jwharm.javagi.interop

Class MemoryCleaner

java.lang.Object

io.github.jwharm.javagi.interop.MemoryCleaner

public class MemoryCleaner
extends Object

This class keeps a cache of all memory addresses for which a Proxy object was created (except for GObject instances; those are handled in the InstanceCache).

When a cached (and owned) Proxy object is garbage-collected, the native memory is released using g_boxed_free, a custom free-function, or (as a last resort), g_free.

When ownership of a memory address transfers to native code, the cleaner will not free the memory. Take and yield ownership with takeOwnership(io.github.jwharm.javagi.base.Proxy) and yieldOwnership(io.github.jwharm.javagi.base.Proxy).

Constructor Summary

Constructors

Constructor	Description
MemoryCleaner()

Method Summary

Modifier and Type	Method	Description
static void	free(MemorySegment address)	Run the MemoryCleaner.StructFinalizer associated with this memory address, by invoking Cleaner.Cleanable.clean().
static void	setBoxedType(@NotNull Proxy proxy, @NotNull Type boxedType)	For a boxed type, g_boxed_free(type, pointer) will be used as cleanup function.
static void	setFreeFunc(@NotNull Proxy proxy, @NotNull String freeFunc)	Register a specialized cleanup function for this proxy instance, instead of the default GLib.free(MemorySegment).
static void	takeOwnership(@NotNull Proxy proxy)	Take ownership of this memory address: when the proxy object is garbage-collected, the memory will automatically be released.
static void	yieldOwnership(@NotNull Proxy proxy)	Yield ownership of this memory address: when the proxy object is garbage-collected, the memory will not be released.

Methods inherited from class java.lang.Object

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

Constructor Details

MemoryCleaner

public MemoryCleaner()

Method Details

setFreeFunc

public static void setFreeFunc(@NotNull
 @NotNull Proxy proxy,
 @NotNull
 @NotNull String freeFunc)

Register a specialized cleanup function for this proxy instance, instead of the default GLib.free(MemorySegment).

Parameters:

proxy - the proxy instance

freeFunc - the specialized cleanup function to call

setBoxedType

public static void setBoxedType(@NotNull
 @NotNull Proxy proxy,
 @NotNull
 @NotNull Type boxedType)

For a boxed type, g_boxed_free(type, pointer) will be used as cleanup function.

Parameters:

proxy - the proxy instance

boxedType - the boxed type

takeOwnership

public static void takeOwnership(@NotNull
 @NotNull Proxy proxy)

Take ownership of this memory address: when the proxy object is garbage-collected, the memory will automatically be released.

Parameters:

proxy - the proxy instance

yieldOwnership

public static void yieldOwnership(@NotNull
 @NotNull Proxy proxy)

Yield ownership of this memory address: when the proxy object is garbage-collected, the memory will not be released.

Parameters:

proxy - the proxy instance

free

public static void free(MemorySegment address)

Run the MemoryCleaner.StructFinalizer associated with this memory address, by invoking Cleaner.Cleanable.clean().

The cleaner action will only ever run once, so any further attempts to free this instance (including by the GC) will be a no-op.

Parameters:

address - the memory address to free