Simple step towards importing structs, add initializeWithCopy funcs

Samples/SwiftKitSampleApp/Sources/MySwiftLibrary/MySwiftClass.swift

@@ -0,0 +1,58 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+public class MySwiftClass {
+
+  public var len: Int
+  public var cap: Int
+
+  public init(len: Int, cap: Int) {
+    self.len = len
+    self.cap = cap
+
+    p("\(MySwiftClass.self).len = \(self.len)")
+    p("\(MySwiftClass.self).cap = \(self.cap)")
+    let addr = unsafeBitCast(self, to: UInt64.self)
+    p("initializer done, self = 0x\(String(addr, radix: 16, uppercase: true))")
+  }
+
+  deinit {
+    let addr = unsafeBitCast(self, to: UInt64.self)
+    p("Deinit, self = 0x\(String(addr, radix: 16, uppercase: true))")
+  }
+
+  public var counter: Int32 = 0
+
+  public func voidMethod() {
+    p("")
+  }
+
+  public func takeIntMethod(i: Int) {
+    p("i:\(i)")
+  }
+
+  public func echoIntMethod(i: Int) -> Int {
+    p("i:\(i)")
+    return i
+  }
+
+  public func makeIntMethod() -> Int {
+    p("make int -> 12")
+    return 12
+  }
+
+  public func makeRandomIntMethod() -> Int {
+    return Int.random(in: 1..<256)
+  }
+}

Samples/SwiftKitSampleApp/Sources/MySwiftLibrary/MySwiftLibrary.swift

@@ -47,68 +47,18 @@ public func globalCallMeRunnable(run: () -> ()) {
   run()
 }
 
-public class MySwiftClass {
-
-  public var len: Int
-  public var cap: Int
-
-  public init(len: Int, cap: Int) {
-    self.len = len
-    self.cap = cap
-
-    p("\(MySwiftClass.self).len = \(self.len)")
-    p("\(MySwiftClass.self).cap = \(self.cap)")
-    let addr = unsafeBitCast(self, to: UInt64.self)
-    p("initializer done, self = 0x\(String(addr, radix: 16, uppercase: true))")
-  }
-
-  deinit {
-    let addr = unsafeBitCast(self, to: UInt64.self)
-    p("Deinit, self = 0x\(String(addr, radix: 16, uppercase: true))")
-  }
-
-  public var counter: Int32 = 0
-
-  public func voidMethod() {
-    p("")
-  }
-
-  public func takeIntMethod(i: Int) {
-    p("i:\(i)")
-  }
-
-  public func echoIntMethod(i: Int) -> Int {
-    p("i:\(i)")
-    return i
-  }
-
-  public func makeIntMethod() -> Int {
-    p("make int -> 12")
-    return 12
-  }
-
-  public func writeString(string: String) -> Int {
-    p("echo -> \(string)")
-    return string.count
-  }
-
-  public func makeRandomIntMethod() -> Int {
-    return Int.random(in: 1..<256)
-  }
-}
-
 // ==== Internal helpers
 
-private func p(_ msg: String, file: String = #fileID, line: UInt = #line, function: String = #function) {
-//  print("[swift][\(file):\(line)](\(function)) \(msg)")
-//  fflush(stdout)
+func p(_ msg: String, file: String = #fileID, line: UInt = #line, function: String = #function) {
+  print("[swift][\(file):\(line)](\(function)) \(msg)")
+  fflush(stdout)
 }
 
-#if os(Linux)
-// FIXME: why do we need this workaround?
-@_silgen_name("_objc_autoreleaseReturnValue")
-public func _objc_autoreleaseReturnValue(a: Any) {}
+ #if os(Linux)
+ // FIXME: why do we need this workaround?
+ @_silgen_name("_objc_autoreleaseReturnValue")
+ public func _objc_autoreleaseReturnValue(a: Any) {}
 
-@_silgen_name("objc_autoreleaseReturnValue")
-public func objc_autoreleaseReturnValue(a: Any) {}
-#endif
+ @_silgen_name("objc_autoreleaseReturnValue")
+ public func objc_autoreleaseReturnValue(a: Any) {}
+ #endif

Samples/SwiftKitSampleApp/Sources/MySwiftLibrary/MySwiftStruct.swift

@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+public struct MySwiftStruct {
+
+  public var number: Int
+
+  public init(number: Int) {
+    self.number = number
+  }
+
+  public func voidMethod() {
+    p("")
+  }
+
+  public func takeIntMethod(i: Int) {
+    p("i:\(i)")
+  }
+
+  public func echoIntMethod(i: Int) -> Int {
+    p("i:\(i)")
+    return i
+  }
+
+  public func makeIntMethod() -> Int {
+    p("make int -> 12")
+    return 12
+  }
+
+  public func makeRandomIntMethod() -> Int {
+    return Int.random(in: 1..<256)
+  }
+}

Samples/SwiftKitSampleApp/Sources/MySwiftLibrary/_RuntimeWorkarounds.swift

@@ -0,0 +1,22 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+#if os(Linux)
+// FIXME: why do we need this workaround?
+@_silgen_name("_objc_autoreleaseReturnValue")
+public func _objc_autoreleaseReturnValue(a: Any) {}
+
+@_silgen_name("objc_autoreleaseReturnValue")
+public func objc_autoreleaseReturnValue(a: Any) {}
+#endif

Samples/SwiftKitSampleApp/src/main/java/com/example/swift/HelloJava2Swift.java

@@ -52,6 +52,9 @@ static void examples() {
 
             obj.voidMethod();
             obj.takeIntMethod(42);
+
+            MySwiftStruct swiftValue = new MySwiftStruct(12);
+
         }
 
         System.out.println("DONE.");

Samples/SwiftKitSampleApp/src/test/java/com/example/swift/MySwiftStructTest.java

@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+package com.example.swift;
+
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
+import org.swift.swiftkit.SwiftArena;
+import org.swift.swiftkit.SwiftKit;
+
+import java.io.File;
+import java.util.stream.Stream;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class MySwiftStructTest {
+
+    @Test
+    void test_MySwiftClass_voidMethod() {
+        try (var arena = SwiftArena.ofConfined()) {
+            MySwiftStruct o = new MySwiftStruct(12);
+//        o.voidMethod();
+        }
+    }
+
+}

Samples/SwiftKitSampleApp/src/test/java/org/swift/swiftkit/SwiftArenaTest.java

@@ -70,6 +70,10 @@ public void arena_releaseClassOnClose_class_leaked() {
             // The message should point out which objects "leaked":
             assertTrue(ex.getMessage().contains(memorySegmentDescription));
         }
+    }
+
+    @Test
+    public void arena_initializeWithCopy_struct() {
 
     }
 }

Sources/ExampleSwiftLibrary/MySwiftLibrary.swift

@@ -97,16 +97,7 @@ public func _getTypeByMangledNameInEnvironment(
 
 // ==== Internal helpers
 
-private func p(_ msg: String, file: String = #fileID, line: UInt = #line, function: String = #function) {
+func p(_ msg: String, file: String = #fileID, line: UInt = #line, function: String = #function) {
   print("[swift][\(file):\(line)](\(function)) \(msg)")
   fflush(stdout)
 }
-
-#if os(Linux)
-// FIXME: why do we need this workaround?
-@_silgen_name("_objc_autoreleaseReturnValue")
-public func _objc_autoreleaseReturnValue(a: Any) {}
-
-@_silgen_name("objc_autoreleaseReturnValue")
-public func objc_autoreleaseReturnValue(a: Any) {}
-#endif

Sources/JExtractSwift/ImportedDecls.swift

@@ -49,6 +49,15 @@ public struct ImportedNominalType: ImportedDecl {
       javaType: javaType
     )
   }
+
+  public var isReferenceType: Bool {
+    switch self.kind {
+    case .class, .actor:
+      return true
+    case .enum, .struct:
+      return false
+    }
+  }
 
   /// The Java class name without the package.
   public var javaClassName: String {

Sources/JExtractSwift/Swift2JavaTranslator+Printing.swift

@@ -194,7 +194,7 @@ extension Swift2JavaTranslator {
     printPackage(&printer)
     printImports(&printer)
 
-    printClass(&printer, decl) { printer in
+    printNominal(&printer, decl) { printer in
       // Prepare type metadata, we're going to need these when invoking e.g. initializers so cache them in a static.
       // We call into source swift-java source generated accessors which give us the type of the Swift object:
       // TODO: seems we no longer need the mangled name per se, so avoiding such constant and downcall
@@ -277,10 +277,17 @@ extension Swift2JavaTranslator {
     printer.print("")
   }
 
-  public func printClass(
+  public func printNominal(
     _ printer: inout CodePrinter, _ decl: ImportedNominalType, body: (inout CodePrinter) -> Void
   ) {
-    printer.printTypeDecl("public final class \(decl.javaClassName) implements SwiftHeapObject") {
+    let parentProtocol: String
+    if decl.isReferenceType {
+      parentProtocol = "SwiftHeapObject"
+    } else {
+      parentProtocol = "SwiftValue"
+    }
+
+    printer.printTypeDecl("public final class \(decl.javaClassName) implements \(parentProtocol)") {
       printer in
       // ==== Storage of the class
       printClassSelfProperty(&printer, decl)

Sources/JExtractSwift/Swift2JavaVisitor.swift

@@ -40,6 +40,7 @@ final class Swift2JavaVisitor: SyntaxVisitor {
   }
 
   override func visit(_ node: ClassDeclSyntax) -> SyntaxVisitorContinueKind {
+    log.debug("Visit \(node.kind): \(node)")
     guard let importedNominalType = translator.importedNominalType(node) else {
       return .skipChildren
     }
@@ -54,7 +55,24 @@ final class Swift2JavaVisitor: SyntaxVisitor {
       currentTypeName = nil
     }
   }
+
+  override func visit(_ node: StructDeclSyntax) -> SyntaxVisitorContinueKind {
+    log.debug("Visit \(node.kind): \(node)")
+    guard let importedNominalType = translator.importedNominalType(node) else {
+      return .skipChildren
+    }
+
+    currentTypeName = importedNominalType.swiftTypeName
+    return .visitChildren
+  }
 
+  override func visitPost(_ node: StructDeclSyntax) {
+    if currentTypeName != nil {
+      log.debug("Completed import: \(node.kind) \(node.name)")
+      currentTypeName = nil
+    }
+  }
+
   override func visit(_ node: ExtensionDeclSyntax) -> SyntaxVisitorContinueKind {
     // Resolve the extended type of the extension as an imported nominal, and
     // recurse if we found it.

SwiftKit/src/main/java/org/swift/swiftkit/ConfinedSwiftMemorySession.java

@@ -36,7 +36,8 @@ public ConfinedSwiftMemorySession(Thread owner) {
 
     public void checkValid() throws RuntimeException {
         if (this.owner != null && this.owner != Thread.currentThread()) {
-            throw new WrongThreadException("ConfinedSwift arena is confined to %s but was closed from %s!".formatted(this.owner, Thread.currentThread()));
+            throw new WrongThreadException("ConfinedSwift arena is confined to %s but was closed from %s!"
+                    .formatted(this.owner, Thread.currentThread()));
         } else if (this.state.get() < ACTIVE) {
             throw new RuntimeException("SwiftArena is already closed!");
         }