[TrimmableTypeMap] Add trimmable [Export] and [ExportField] callback support

src/Microsoft.Android.Sdk.TrimmableTypeMap/Generator/ExportMethodDispatchEmitterContext.cs

@@ -0,0 +1,228 @@
+using System.Reflection.Metadata;
+using System.Reflection.Metadata.Ecma335;
+
+namespace Microsoft.Android.Sdk.TrimmableTypeMap;
+
+/// <summary>
+/// Holds pre-resolved metadata references needed by <see cref="ExportMethodDispatchEmitter"/>
+/// for generating [Export] method dispatch IL. Created once per emit pass and reused
+/// for all export methods.
+/// </summary>
+sealed class ExportMethodDispatchEmitterContext
+{
+	public static ExportMethodDispatchEmitterContext Create (
+		PEAssemblyBuilder pe,
+		TypeReferenceHandle iJavaPeerableRef,
+		TypeReferenceHandle jniHandleOwnershipRef,
+		TypeReferenceHandle jniEnvRef,
+		TypeReferenceHandle systemTypeRef,
+		MemberReferenceHandle getTypeFromHandleRef,
+		MemberReferenceHandle ucoAttrCtorRef,
+		BlobHandle ucoAttrBlobHandle,
+		TypeReferenceHandle jniTransitionRef,
+		TypeReferenceHandle jniRuntimeRef,
+		TypeReferenceHandle exceptionRef,
+		MemberReferenceHandle beginMarshalMethodRef,
+		MemberReferenceHandle endMarshalMethodRef,
+		MemberReferenceHandle onUserUnhandledExceptionRef)
+	{
+		var metadata = pe.Metadata;
+		var iJavaObjectRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("IJavaObject"));
+		var javaLangObjectRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Java.Lang"), metadata.GetOrAddString ("Object"));
+		var systemArrayRef = metadata.AddTypeReference (pe.SystemRuntimeRef,
+			metadata.GetOrAddString ("System"), metadata.GetOrAddString ("Array"));
+		var systemStreamRef = metadata.AddTypeReference (pe.SystemRuntimeRef,
+			metadata.GetOrAddString ("System.IO"), metadata.GetOrAddString ("Stream"));
+		var systemXmlRef = pe.FindOrAddAssemblyRef ("System.Xml.ReaderWriter");
+		var systemXmlReaderRef = metadata.AddTypeReference (systemXmlRef,
+			metadata.GetOrAddString ("System.Xml"), metadata.GetOrAddString ("XmlReader"));
+		var inputStreamInvokerRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("InputStreamInvoker"));
+		var outputStreamInvokerRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("OutputStreamInvoker"));
+		var inputStreamAdapterRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("InputStreamAdapter"));
+		var outputStreamAdapterRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("OutputStreamAdapter"));
+		var xmlPullParserReaderRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("XmlPullParserReader"));
+		var xmlResourceParserReaderRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("XmlResourceParserReader"));
+		var xmlReaderPullParserRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("XmlReaderPullParser"));
+		var xmlReaderResourceParserRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("XmlReaderResourceParser"));
+		var charSequenceRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("CharSequence"));
+		var iCharSequenceRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Java.Lang"), metadata.GetOrAddString ("ICharSequence"));
+		var javaListRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("JavaList"));
+		var javaDictionaryRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("JavaDictionary"));
+		var javaCollectionRef = metadata.AddTypeReference (pe.MonoAndroidRef,
+			metadata.GetOrAddString ("Android.Runtime"), metadata.GetOrAddString ("JavaCollection"));
+		var systemCollectionsIListRef = metadata.AddTypeReference (pe.SystemRuntimeRef,
+			metadata.GetOrAddString ("System.Collections"), metadata.GetOrAddString ("IList"));
+		var systemCollectionsIDictionaryRef = metadata.AddTypeReference (pe.SystemRuntimeRef,
+			metadata.GetOrAddString ("System.Collections"), metadata.GetOrAddString ("IDictionary"));
+		var systemCollectionsICollectionRef = metadata.AddTypeReference (pe.SystemRuntimeRef,
+			metadata.GetOrAddString ("System.Collections"), metadata.GetOrAddString ("ICollection"));
+
+		return new ExportMethodDispatchEmitterContext {
+			IJavaObjectRef = iJavaObjectRef,
+			GetTypeFromHandleRef = getTypeFromHandleRef,
+			JniEnvGetStringRef = pe.AddMemberRef (jniEnvRef, "GetString",
+				sig => sig.MethodSignature ().Parameters (2,
+					rt => rt.Type ().String (),
+					p => {
+						p.AddParameter ().Type ().IntPtr ();
+						p.AddParameter ().Type ().Type (jniHandleOwnershipRef, true);
+					})),
+			JniEnvGetArrayRef = pe.AddMemberRef (jniEnvRef, "GetArray",
+				sig => sig.MethodSignature ().Parameters (3,
+					rt => rt.Type ().Type (systemArrayRef, false),
+					p => {
+						p.AddParameter ().Type ().IntPtr ();
+						p.AddParameter ().Type ().Type (jniHandleOwnershipRef, true);
+						p.AddParameter ().Type ().Type (systemTypeRef, false);
+					})),
+			JniEnvCopyArrayRef = pe.AddMemberRef (jniEnvRef, "CopyArray",
+				sig => sig.MethodSignature ().Parameters (3,
+					rt => rt.Void (),
+					p => {
+						p.AddParameter ().Type ().Type (systemArrayRef, false);
+						p.AddParameter ().Type ().Type (systemTypeRef, false);
+						p.AddParameter ().Type ().IntPtr ();
+					})),
+			JniEnvNewArrayRef = pe.AddMemberRef (jniEnvRef, "NewArray",
+				sig => sig.MethodSignature ().Parameters (2,
+					rt => rt.Type ().IntPtr (),
+					p => {
+						p.AddParameter ().Type ().Type (systemArrayRef, false);
+						p.AddParameter ().Type ().Type (systemTypeRef, false);
+					})),
+			JniEnvNewStringRef = pe.AddMemberRef (jniEnvRef, "NewString",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().String ())),
+			JniEnvToLocalJniHandleRef = pe.AddMemberRef (jniEnvRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (iJavaObjectRef, false))),
+			JavaLangObjectGetObjectRef = pe.AddMemberRef (javaLangObjectRef, "GetObject",
+				sig => sig.MethodSignature ().Parameters (3,
+					rt => rt.Type ().Type (iJavaPeerableRef, false),
+					p => {
+						p.AddParameter ().Type ().IntPtr ();
+						p.AddParameter ().Type ().Type (jniHandleOwnershipRef, true);
+						p.AddParameter ().Type ().Type (systemTypeRef, false);
+					})),
+			InputStreamInvokerFromJniHandleRef = pe.AddMemberRef (inputStreamInvokerRef, "FromJniHandle",
+				sig => sig.MethodSignature ().Parameters (2,
+					rt => rt.Type ().Type (systemStreamRef, false),
+					p => {
+						p.AddParameter ().Type ().IntPtr ();
+						p.AddParameter ().Type ().Type (jniHandleOwnershipRef, true);
+					})),
+			OutputStreamInvokerFromJniHandleRef = pe.AddMemberRef (outputStreamInvokerRef, "FromJniHandle",
+				sig => sig.MethodSignature ().Parameters (2,
+					rt => rt.Type ().Type (systemStreamRef, false),
+					p => {
+						p.AddParameter ().Type ().IntPtr ();
+						p.AddParameter ().Type ().Type (jniHandleOwnershipRef, true);
+					})),
+			InputStreamAdapterToLocalJniHandleRef = pe.AddMemberRef (inputStreamAdapterRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (systemStreamRef, false))),
+			OutputStreamAdapterToLocalJniHandleRef = pe.AddMemberRef (outputStreamAdapterRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (systemStreamRef, false))),
+			XmlPullParserReaderFromJniHandleRef = pe.AddMemberRef (xmlPullParserReaderRef, "FromJniHandle",
+				sig => sig.MethodSignature ().Parameters (2,
+					rt => rt.Type ().Type (systemXmlReaderRef, false),
+					p => {
+						p.AddParameter ().Type ().IntPtr ();
+						p.AddParameter ().Type ().Type (jniHandleOwnershipRef, true);
+					})),
+			XmlResourceParserReaderFromJniHandleRef = pe.AddMemberRef (xmlResourceParserReaderRef, "FromJniHandle",
+				sig => sig.MethodSignature ().Parameters (2,
+					rt => rt.Type ().Type (systemXmlReaderRef, false),
+					p => {
+						p.AddParameter ().Type ().IntPtr ();
+						p.AddParameter ().Type ().Type (jniHandleOwnershipRef, true);
+					})),
+			XmlReaderPullParserToLocalJniHandleRef = pe.AddMemberRef (xmlReaderPullParserRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (systemXmlReaderRef, false))),
+			XmlReaderResourceParserToLocalJniHandleRef = pe.AddMemberRef (xmlReaderResourceParserRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (systemXmlReaderRef, false))),
+			CharSequenceToLocalJniHandleRef = pe.AddMemberRef (charSequenceRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (iCharSequenceRef, false))),
+			JavaListToLocalJniHandleRef = pe.AddMemberRef (javaListRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (systemCollectionsIListRef, false))),
+			JavaDictionaryToLocalJniHandleRef = pe.AddMemberRef (javaDictionaryRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (systemCollectionsIDictionaryRef, false))),
+			JavaCollectionToLocalJniHandleRef = pe.AddMemberRef (javaCollectionRef, "ToLocalJniHandle",
+				sig => sig.MethodSignature ().Parameters (1,
+					rt => rt.Type ().IntPtr (),
+					p => p.AddParameter ().Type ().Type (systemCollectionsICollectionRef, false))),
+			UcoAttrCtorRef = ucoAttrCtorRef,
+			UcoAttrBlobHandle = ucoAttrBlobHandle,
+			JniTransitionRef = jniTransitionRef,
+			JniRuntimeRef = jniRuntimeRef,
+			ExceptionRef = exceptionRef,
+			BeginMarshalMethodRef = beginMarshalMethodRef,
+			EndMarshalMethodRef = endMarshalMethodRef,
+			OnUserUnhandledExceptionRef = onUserUnhandledExceptionRef,
+		};
+	}
+
+	public required TypeReferenceHandle IJavaObjectRef { get; init; }
+	public required MemberReferenceHandle GetTypeFromHandleRef { get; init; }
+	public required MemberReferenceHandle JniEnvGetStringRef { get; init; }
+	public required MemberReferenceHandle JniEnvGetArrayRef { get; init; }
+	public required MemberReferenceHandle JniEnvCopyArrayRef { get; init; }
+	public required MemberReferenceHandle JniEnvNewArrayRef { get; init; }
+	public required MemberReferenceHandle JniEnvNewStringRef { get; init; }
+	public required MemberReferenceHandle JniEnvToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle JavaLangObjectGetObjectRef { get; init; }
+	public required MemberReferenceHandle InputStreamInvokerFromJniHandleRef { get; init; }
+	public required MemberReferenceHandle OutputStreamInvokerFromJniHandleRef { get; init; }
+	public required MemberReferenceHandle InputStreamAdapterToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle OutputStreamAdapterToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle XmlPullParserReaderFromJniHandleRef { get; init; }
+	public required MemberReferenceHandle XmlResourceParserReaderFromJniHandleRef { get; init; }
+	public required MemberReferenceHandle XmlReaderPullParserToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle XmlReaderResourceParserToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle CharSequenceToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle JavaListToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle JavaDictionaryToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle JavaCollectionToLocalJniHandleRef { get; init; }
+	public required MemberReferenceHandle UcoAttrCtorRef { get; init; }
+
+	public required BlobHandle UcoAttrBlobHandle { get; init; }
+
+	// Marshal-method wrapper plumbing — mirrors the UCO ctor wrapper used by
+	// TypeMapAssemblyEmitter so that managed exceptions thrown from [Export] method
+	// bodies surface as Java exceptions instead of crashing the runtime.
+	public required TypeReferenceHandle JniTransitionRef { get; init; }
+	public required TypeReferenceHandle JniRuntimeRef { get; init; }
+	public required TypeReferenceHandle ExceptionRef { get; init; }
+	public required MemberReferenceHandle BeginMarshalMethodRef { get; init; }
+	public required MemberReferenceHandle EndMarshalMethodRef { get; init; }
+	public required MemberReferenceHandle OnUserUnhandledExceptionRef { get; init; }
+}

src/Microsoft.Android.Sdk.TrimmableTypeMap/Generator/JcwJavaSourceGenerator.cs

@@ -249,7 +249,7 @@ static void WriteMethods (JavaPeerInfo type, TextWriter writer)
 				throwsClause = $"\n\t\tthrows {string.Join (", ", method.ThrownNames)}";
 			}
 
-			if (method.Connector != null) {
+			if (method.Connector != null && !method.IsExport) {
 				writer.Write ($$"""
 
 	@Override
@@ -262,13 +262,14 @@ static void WriteMethods (JavaPeerInfo type, TextWriter writer)
 """);
 			} else {
 				string access = method.IsExport && method.JavaAccess != null ? method.JavaAccess : "public";
+				string staticKeyword = method.IsStatic ? "static " : "";
 				writer.Write ($$"""
 
-	{{access}} {{javaReturnType}} {{method.JniName}} ({{parameters}}){{throwsClause}}
+	{{access}} {{staticKeyword}}{{javaReturnType}} {{method.JniName}} ({{parameters}}){{throwsClause}}
 	{
 {{registerNativesLine}}		{{returnPrefix}}{{method.NativeCallbackName}} ({{args}});
 	}
-	{{access}} native {{javaReturnType}} {{method.NativeCallbackName}} ({{parameters}});
+	{{access}} {{staticKeyword}}native {{javaReturnType}} {{method.NativeCallbackName}} ({{parameters}});
 
 """);
 			}

src/Microsoft.Android.Sdk.TrimmableTypeMap/Generator/Model/TypeMapAssemblyData.cs

@@ -142,6 +142,13 @@ sealed class JavaPeerProxyData
 	/// </summary>
 	public bool IsGenericDefinition { get; init; }
 
+	/// <summary>
+	/// True when the Java stub must not call RegisterNatives from a static initializer because
+	/// the type can be instantiated before the runtime is fully ready (for example Application
+	/// or Instrumentation subclasses).
+	/// </summary>
+	public bool CannotRegisterInStaticConstructor { get; init; }
+
 	/// <summary>
 	/// Whether this proxy needs ACW support (RegisterNatives + UCO wrappers + IAndroidCallableWrapper).
 	/// </summary>
@@ -166,7 +173,7 @@ sealed class JavaPeerProxyData
 /// <summary>
 /// A cross-assembly type reference (assembly name + full managed type name).
 /// </summary>
-sealed record TypeRefData
+public sealed record TypeRefData
 {
 	/// <summary>
 	/// Full managed type name, e.g., "Android.App.Activity" or "MyApp.Outer+Inner".
@@ -177,11 +184,19 @@ sealed record TypeRefData
 	/// Assembly containing the type, e.g., "Mono.Android".
 	/// </summary>
 	public required string AssemblyName { get; init; }
+
+	/// <summary>
+	/// True if this type — or, for array types, the element type — is an enum.
+	/// Used by the IL emitter to encode the type as <c>ELEMENT_TYPE_VALUETYPE</c>
+	/// rather than <c>ELEMENT_TYPE_CLASS</c> in member references and signatures.
+	/// </summary>
+	public bool IsEnum { get; init; }
 }
 
 /// <summary>
 /// An [UnmanagedCallersOnly] static wrapper for a marshal method.
-/// Body: load all args → call n_* callback → ret.
+/// Body: either forward to an existing n_* callback or dispatch directly to the
+/// managed export target when the trimmable path can avoid dynamic callback generation.
 /// </summary>
 sealed record UcoMethodData
 {
@@ -191,7 +206,7 @@ sealed record UcoMethodData
 	public required string WrapperName { get; init; }
 
 	/// <summary>
-	/// Name of the n_* callback to call, e.g., "n_OnCreate".
+	/// Java/JNI-visible native method name, e.g., "n_OnCreate".
 	/// </summary>
 	public required string CallbackMethodName { get; init; }
 
@@ -205,6 +220,52 @@ sealed record UcoMethodData
 	/// </summary>
 	public required string JniSignature { get; init; }
 
+	/// <summary>
+	/// Optional [Export]-only metadata for wrappers that dispatch directly to the
+	/// managed export target instead of forwarding to a generated n_* callback.
+	/// </summary>
+	public ExportMethodDispatchData? ExportMethodDispatch { get; init; }
+
+	/// <summary>
+	/// True when this wrapper performs the static [Export] direct-dispatch path.
+	/// </summary>
+	public bool UsesExportMethodDispatch => ExportMethodDispatch != null;
+}
+
+sealed record ExportMethodDispatchData
+{
+	/// <summary>
+	/// Managed method name on the callback type that should be invoked for [Export].
+	/// </summary>
+	public required string ManagedMethodName { get; init; }
+
+	/// <summary>
+	/// Managed parameter types for the target method, including the defining assembly.
+	/// </summary>
+	public IReadOnlyList<TypeRefData> ParameterTypes { get; init; } = [];
+
+	/// <summary>
+	/// Per-parameter [ExportParameter] kinds for legacy callback marshalling.
+	/// </summary>
+	public IReadOnlyList<ExportParameterKindInfo> ParameterKinds { get; init; } = [];
+
+	/// <summary>
+	/// Managed return type for the target method, including the defining assembly.
+	/// </summary>
+	public TypeRefData ReturnType { get; init; } = new () {
+		ManagedTypeName = "System.Void",
+		AssemblyName = "System.Runtime",
+	};
+
+	/// <summary>
+	/// [ExportParameter] kind applied to the return value, if any.
+	/// </summary>
+	public ExportParameterKindInfo ReturnKind { get; init; }
+
+	/// <summary>
+	/// Whether the managed target method is static.
+	/// </summary>
+	public bool IsStatic { get; init; }
 }
 
 /// <summary>
@@ -231,14 +292,22 @@ sealed record UcoConstructorData
 	public required string JniSignature { get; init; }
 
 	/// <summary>
-	/// Managed constructor parameter type names, in declaration order.
+	/// <see langword="true"/> when the UCO codegen can statically prove the managed
+	/// type defines a matching user-visible ctor with this signature. When
+	/// <see langword="false"/>, the codegen must use the legacy activation-ctor
+	/// `(IntPtr, JniHandleOwnership)` path instead of emitting a member ref to
+	/// a (potentially non-existent) user ctor.
 	/// </summary>
-	public IReadOnlyList<string> ManagedParameterTypes { get; init; } = [];
+	public required bool HasMatchingManagedCtor { get; init; }
 
 	/// <summary>
-	/// True when this Java constructor has a matching managed constructor on the target type.
+	/// Managed parameter types of the matching user-visible ctor, in declaration
+	/// order. Empty for `()V`. Non-empty when <see cref="HasMatchingManagedCtor"/>
+	/// is <see langword="true"/> and the ctor takes parameters; the emitter uses
+	/// this to build the member ref signature and to marshal each JNI argument
+	/// to the corresponding managed type before calling the user ctor.
 	/// </summary>
-	public bool HasManagedConstructor { get; init; }
+	public IReadOnlyList<TypeRefData> ManagedParameterTypes { get; init; } = [];
 }
 
 /// <summary>