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[Mono.Android] call new Java "GC Bridge" APIs #10125

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0ae638d
[Mono.Android] call new Java "GC Bridge" APIs
jonathanpeppers May 8, 2025
f4a2148
What if everything was managed-only?
jonathanpeppers May 8, 2025
aa0a4ae
Now uses: https://github.com/dotnet/java-interop/pull/1334
jonathanpeppers May 12, 2025
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2 changes: 2 additions & 0 deletions .gitattributes
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Expand Up @@ -35,3 +35,5 @@ Makefile eol=lf
*.wixproj eol=crlf
*.wxs eol=crlf
*.rtf eol=crlf

packages/* filter=lfs diff=lfs merge=lfs -text
25 changes: 19 additions & 6 deletions Documentation/workflow/DevelopmentTips.md
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Expand Up @@ -450,13 +450,26 @@ A second (better) way is to add this MSBuild target to your Android
`.csproj` file:

```xml
<Target Name="UpdateMonoRuntimePacks" BeforeTargets="ProcessFrameworkReferences">
<Target Name="UpdateRuntimeVersion" BeforeTargets="ProcessFrameworkReferences">
<PropertyGroup>
<!-- This could be a version I built myself -->
<_Version>10.0.0-dev</_Version>
</PropertyGroup>
<ItemGroup>
<KnownRuntimePack
Update="Microsoft.NETCore.App"
Condition=" '%(KnownRuntimePack.TargetFramework)' == 'net6.0' "
LatestRuntimeFrameworkVersion="6.0.0-preview.7.21364.3"
/>
<!-- For runtime packs only -->
<KnownRuntimePack
Update="Microsoft.NETCore.App"
Condition=" '%(KnownRuntimePack.TargetFramework)' == 'net10.0' "
LatestRuntimeFrameworkVersion="$(_Version)"
/>
<!-- For new .NET APIs -->
<KnownFrameworkReference
Update="Microsoft.NETCore.App"
Condition=" '%(KnownFrameworkReference.TargetFramework)' == 'net10.0' "
DefaultRuntimeFrameworkVersion="$(_Version)"
LatestRuntimeFrameworkVersion="$(_Version)"
TargetingPackVersion="$(_Version)"
/>
</ItemGroup>
</Target>
```
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1 change: 1 addition & 0 deletions NuGet.config
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Expand Up @@ -7,6 +7,7 @@
<!-- End: Package sources from dotnet-android -->
<!--End: Package sources managed by Dependency Flow automation. Do not edit the sources above.-->
<!-- ensure only the sources defined below are used -->
<add key="local-packages" value="packages" />
<add key="dotnet-public" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-public/nuget/v3/index.json" protocolVersion="3" />
<add key="dotnet-eng" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-eng/nuget/v3/index.json" protocolVersion="3" />
<!-- This is for packages needed by debugger-libs -->
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21 changes: 21 additions & 0 deletions build-tools/scripts/custom-runtime.targets
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@@ -0,0 +1,21 @@
<Project>
<!-- Use version in local packages folder -->
<Target Name="UpdateRuntimeVersion" BeforeTargets="ProcessFrameworkReferences">
<PropertyGroup>
<_Version>10.0.0-dev</_Version>
</PropertyGroup>
<ItemGroup>
<KnownFrameworkReference Update="Microsoft.NETCore.App"
Condition=" '%(KnownFrameworkReference.TargetFramework)' == 'net10.0' "
DefaultRuntimeFrameworkVersion="$(_Version)"
LatestRuntimeFrameworkVersion="$(_Version)"
TargetingPackVersion="$(_Version)"
/>
<KnownRuntimePack
Update="Microsoft.NETCore.App"
Condition=" '%(KnownRuntimePack.TargetFramework)' == 'net10.0' "
LatestRuntimeFrameworkVersion="$(_Version)"
/>
</ItemGroup>
</Target>
</Project>
2 changes: 1 addition & 1 deletion external/Java.Interop
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Submodule Java.Interop updated 7 files
+2 −0 src/Java.Interop/Java.Interop/IJavaPeerable.cs
+19 −10 src/Java.Interop/Java.Interop/JavaException.cs
+20 −11 src/Java.Interop/Java.Interop/JavaObject.cs
+27 −0 src/Java.Interop/Java.Interop/JniObjectReferenceControlBlock.cs
+1 −0 src/Java.Interop/PublicAPI.Unshipped.txt
+71 −67 src/java-interop/java-interop-gc-bridge-mono.cc
+67 −0 src/utils/NullableAttributes.cs
3 changes: 3 additions & 0 deletions packages/Microsoft.NETCore.App.Ref.10.0.0-dev.nupkg
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3 changes: 3 additions & 0 deletions packages/Microsoft.NETCore.App.Runtime.android-arm64.10.0.0-dev.nupkg
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65 changes: 46 additions & 19 deletions src/Mono.Android/Microsoft.Android.Runtime/ManagedValueManager.cs
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Expand Up @@ -10,6 +10,7 @@
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.Java;
using System.Threading;
using Android.Runtime;
using Java.Interop;
Expand All @@ -20,10 +21,11 @@ class ManagedValueManager : JniRuntime.JniValueManager
{
const DynamicallyAccessedMemberTypes Constructors = DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors;

Dictionary<int, List<IJavaPeerable>>? RegisteredInstances = new Dictionary<int, List<IJavaPeerable>>();
Dictionary<int, List<GCHandle>>? RegisteredInstances = new ();

internal ManagedValueManager ()
internal unsafe ManagedValueManager ()
{
JavaMarshal.Initialize (&FinishBridgeProcessing);
}

public override void WaitForGCBridgeProcessing ()
Expand All @@ -35,7 +37,7 @@ public override void CollectPeers ()
if (RegisteredInstances == null)
throw new ObjectDisposedException (nameof (ManagedValueManager));

var peers = new List<IJavaPeerable> ();
var peers = new List<GCHandle> ();

lock (RegisteredInstances) {
foreach (var ps in RegisteredInstances.Values) {
Expand All @@ -48,7 +50,8 @@ public override void CollectPeers ()
List<Exception>? exceptions = null;
foreach (var peer in peers) {
try {
peer.Dispose ();
if (peer.Target is IDisposable disposable)
disposable.Dispose ();
}
catch (Exception e) {
exceptions = exceptions ?? new List<Exception> ();
Expand All @@ -74,33 +77,35 @@ public override void AddPeer (IJavaPeerable value)
}
int key = value.JniIdentityHashCode;
lock (RegisteredInstances) {
List<IJavaPeerable>? peers;
List<GCHandle>? peers;
if (!RegisteredInstances.TryGetValue (key, out peers)) {
peers = new List<IJavaPeerable> () {
value,
peers = new List<GCHandle> () {
CreateReferenceTrackingHandle (value)
};
RegisteredInstances.Add (key, peers);
return;
}

for (int i = peers.Count - 1; i >= 0; i--) {
var p = peers [i];
if (!JniEnvironment.Types.IsSameObject (p.PeerReference, value.PeerReference))
if (p.Target is not IJavaPeerable peer)
continue;
if (!JniEnvironment.Types.IsSameObject (peer.PeerReference, value.PeerReference))
continue;
if (Replaceable (p)) {
peers [i] = value;
peers [i] = CreateReferenceTrackingHandle (value);
} else {
WarnNotReplacing (key, value, p);
WarnNotReplacing (key, value, peer);
}
return;
}
peers.Add (value);
peers.Add (CreateReferenceTrackingHandle (value));
}
}

static bool Replaceable (IJavaPeerable peer)
static bool Replaceable (GCHandle handle)
{
if (peer == null)
if (handle.Target is not IJavaPeerable peer)
return true;
return peer.JniManagedPeerState.HasFlag (JniManagedPeerStates.Replaceable);
}
Expand Down Expand Up @@ -132,14 +137,14 @@ void WarnNotReplacing (int key, IJavaPeerable ignoreValue, IJavaPeerable keepVal
int key = GetJniIdentityHashCode (reference);

lock (RegisteredInstances) {
List<IJavaPeerable>? peers;
List<GCHandle>? peers;
if (!RegisteredInstances.TryGetValue (key, out peers))
return null;

for (int i = peers.Count - 1; i >= 0; i--) {
var p = peers [i];
if (JniEnvironment.Types.IsSameObject (reference, p.PeerReference))
return p;
if (p.Target is IJavaPeerable peer && JniEnvironment.Types.IsSameObject (reference, peer.PeerReference))
return peer;
}
if (peers.Count == 0)
RegisteredInstances.Remove (key);
Expand All @@ -157,14 +162,15 @@ public override void RemovePeer (IJavaPeerable value)

int key = value.JniIdentityHashCode;
lock (RegisteredInstances) {
List<IJavaPeerable>? peers;
List<GCHandle>? peers;
if (!RegisteredInstances.TryGetValue (key, out peers))
return;

for (int i = peers.Count - 1; i >= 0; i--) {
var p = peers [i];
if (object.ReferenceEquals (value, p)) {
if (object.ReferenceEquals (value, p.Target)) {
peers.RemoveAt (i);
FreeHandle (p);
}
}
if (peers.Count == 0)
Expand Down Expand Up @@ -251,13 +257,34 @@ public override List<JniSurfacedPeerInfo> GetSurfacedPeers ()
var peers = new List<JniSurfacedPeerInfo> (RegisteredInstances.Count);
foreach (var e in RegisteredInstances) {
foreach (var p in e.Value) {
peers.Add (new JniSurfacedPeerInfo (e.Key, new WeakReference<IJavaPeerable> (p)));
if (p.Target is not IJavaPeerable peer)
continue;
peers.Add (new JniSurfacedPeerInfo (e.Key, new WeakReference<IJavaPeerable> (peer)));
}
}
return peers;
}
}

static GCHandle CreateReferenceTrackingHandle (IJavaPeerable value) =>
JavaMarshal.CreateReferenceTrackingHandle (value, value.JniObjectReferenceControlBlock);

static unsafe void FreeHandle (GCHandle handle)
{
IntPtr context = JavaMarshal.GetContext (handle);
NativeMemory.Free ((void*) context);
}

[UnmanagedCallersOnly]
internal static unsafe void FinishBridgeProcessing (nint sccsLen, StronglyConnectedComponent* sccs, nint ccrsLen, ComponentCrossReference* ccrs)
{
Java.Lang.JavaSystem.Gc ();
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This is the C# binding of java.lang.System.gc(): https://developer.android.com/reference/java/lang/System#gc()


JavaMarshal.ReleaseMarkCrossReferenceResources (
new Span<StronglyConnectedComponent> (sccs, (int) sccsLen),
new Span<ComponentCrossReference> (ccrs, (int) ccrsLen));
}

const BindingFlags ActivationConstructorBindingFlags = BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance;

static readonly Type[] XAConstructorSignature = new Type [] { typeof (IntPtr), typeof (JniHandleOwnership) };
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1 change: 1 addition & 0 deletions src/Mono.Android/Mono.Android.csproj
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Expand Up @@ -113,6 +113,7 @@
<Import Project="..\Xamarin.Android.NamingCustomAttributes\Xamarin.Android.NamingCustomAttributes.projitems" Label="Shared" Condition="Exists('..\Xamarin.Android.NamingCustomAttributes\Xamarin.Android.NamingCustomAttributes.projitems')" />
<Import Project="Mono.Android.targets" />
<Import Project="..\..\build-tools\scripts\JavaCallableWrappers.targets" />
<Import Project="..\..\build-tools\scripts\custom-runtime.targets" />
<Import Project="$(IntermediateOutputPath)mcw\Mono.Android.projitems" Condition="Exists('$(IntermediateOutputPath)mcw\Mono.Android.projitems')" />

<ItemGroup>
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