jextract prebuil plugin; without swift interfaces; triggered by gradle

Author: ktoso

Plugins/JExtractSwiftPlugin/JExtractSwiftPlugin.swift

@@ -19,39 +19,41 @@ import PackagePlugin
 struct JExtractSwiftBuildToolPlugin: BuildToolPlugin {
   func createBuildCommands(context: PluginContext, target: Target) throws -> [Command] {
     guard let sourceModule = target.sourceModule else { return [] }
-    
+
     // Note: Target doesn't have a directoryURL counterpart to directory,
     // so we cannot eliminate this deprecation warning.
     let sourceDir = target.directory.string
-    
+
     let configuration = try readConfiguration(sourceDir: "\(sourceDir)")
-    
+
     // We use the the usual maven-style structure of "src/[generated|main|test]/java/..."
     // that is common in JVM ecosystem
-    let outputDirectory = context.pluginWorkDirectoryURL
+    let outputDirectoryJava = context.pluginWorkDirectoryURL
       .appending(path: "src")
       .appending(path: "generated")
       .appending(path: "java")
-    
+    let outputDirectorySwift = context.pluginWorkDirectoryURL
+
     var arguments: [String] = [
       "--swift-module", sourceModule.name,
       "--package-name", configuration.javaPackage,
-      "--output-directory", outputDirectory.path(percentEncoded: false),
+      "--output-directory-java", outputDirectoryJava.path(percentEncoded: false),
+      "--output-directory-swift", outputDirectorySwift.path(percentEncoded: false),
       // TODO: "--build-cache-directory", ...
       //       Since plugins cannot depend on libraries we cannot detect what the output files will be,
       //       as it depends on the contents of the input files. Therefore we have to implement this as a prebuild plugin.
       //       We'll have to make up some caching inside the tool so we don't re-parse files which have not changed etc.
     ]
     arguments.append(sourceDir)
-    
+
     return [
       .prebuildCommand(
         displayName: "Generate Java wrappers for Swift types",
         executable: try context.tool(named: "JExtractSwiftTool").url,
         arguments: arguments,
         // inputFiles: [ configFile ] + swiftFiles,
         // outputFiles: outputJavaFiles
-        outputFilesDirectory: outputDirectory
+        outputFilesDirectory: outputDirectorySwift
       )
     ]
   }
@@ -64,17 +66,17 @@ func findJavaHome() -> String {
   if let home = ProcessInfo.processInfo.environment["JAVA_HOME"] {
     return home
   }
-  
+
   // This is a workaround for envs (some IDEs) which have trouble with
   // picking up env variables during the build process
   let path = "\(FileManager.default.homeDirectoryForCurrentUser.path()).java_home"
   if let home = try? String(contentsOfFile: path, encoding: .utf8) {
     if let lastChar = home.last, lastChar.isNewline {
       return String(home.dropLast())
     }
-    
+
     return home
   }
-  
+
   fatalError("Please set the JAVA_HOME environment variable to point to where Java is installed.")
 }

Samples/JExtractPluginSampleApp/Package.swift

@@ -44,12 +44,19 @@ let package = Package(
     platforms: [
         .macOS(.v10_15),
     ],
-    dependencies: [
+   products: [
+     .library(
+       name: "JExtractPluginSampleLib",
+       type: .dynamic,
+       targets: ["JExtractPluginSampleLib"]
+     ),
+   ],
+   dependencies: [
         .package(name: "swift-java", path: "../../"),
     ],
     targets: [
-        .executableTarget(
-            name: "JExtractPluginSample",
+        .target(
+            name: "JExtractPluginSampleLib",
             dependencies: [
             ],
             swiftSettings: [

Samples/JExtractPluginSampleApp/Sources/JExtractPluginSample/JExtractSwift.config renamed to Samples/JExtractPluginSampleApp/Sources/JExtractPluginSampleLib/JExtractSwift.config

@@ -12,6 +12,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-public class MyCoolLibrary {
+public class MyCoolSwiftClass {
+  public init(number: Int) {}
   public func exposedToJava() { }
 }

Samples/JExtractPluginSampleApp/Sources/JExtractPluginSample/main.swift renamed to Samples/JExtractPluginSampleApp/Sources/JExtractPluginSampleLib/MyCoolSwiftClass.swift

@@ -0,0 +1,91 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+import org.swift.swiftkit.gradle.BuildUtils
+
+plugins {
+    id("build-logic.java-application-conventions")
+//     id("me.champeau.jmh") version "0.7.2"
+}
+
+group = "org.swift.swiftkit"
+version = "1.0-SNAPSHOT"
+
+repositories {
+    mavenCentral()
+}
+
+java {
+    toolchain {
+        languageVersion.set(JavaLanguageVersion.of(22))
+    }
+}
+
+
+def jextract = tasks.register("swift-build", Exec) {
+    description = "Builds swift sources, including swift-java source generation"
+
+    // monitor project Swift sources:
+    inputs.dir(layout.projectDirectory.dir("Sources/"))
+
+    // monitor root java-swift sources (including source generator libs which may be changing):
+    inputs.dir("$rootDir/Sources")
+
+    // the swift-java produced Java sources are located here:
+    outputs.dir(layout.buildDirectory.dir("../.build/plugins/outputs/jextractpluginsampleapp/JExtractPluginSampleLib/destination/JExtractSwiftPlugin/src/generated/java"))
+
+    workingDir = rootDir
+    commandLine "swift"
+    args "build"
+}
+
+// Add the java-swift generated Java sources
+sourceSets {
+    main {
+        java {
+            srcDir(jextract)
+        }
+    }
+}
+
+dependencies {
+    implementation(project(':SwiftKit'))
+
+    testImplementation(platform("org.junit:junit-bom:5.10.0"))
+    testImplementation("org.junit.jupiter:junit-jupiter")
+}
+
+tasks.named('test', Test) {
+    useJUnitPlatform()
+}
+
+application {
+    mainClass = "com.example.swift.HelloJava2Swift"
+
+    // In order to silence:
+    //   WARNING: A restricted method in java.lang.foreign.SymbolLookup has been called
+    //   WARNING: java.lang.foreign.SymbolLookup::libraryLookup has been called by org.example.swift.JavaKitExample in an unnamed module
+    //   WARNING: Use --enable-native-access=ALL-UNNAMED to avoid a warning for callers in this module
+    //   WARNING: Restricted methods will be blocked in a future release unless native access is enabled
+    // FIXME: Find out the proper solution to this
+    applicationDefaultJvmArgs = [
+        "--enable-native-access=ALL-UNNAMED",
+
+        // Include the library paths where our dylibs are that we want to load and call
+        "-Djava.library.path=" + BuildUtils.javaLibraryPaths(rootDir).join(":"),
+
+        // Enable tracing downcalls (to Swift)
+        "-Djextract.trace.downcalls=true"
+    ]
+}

Samples/JExtractPluginSampleApp/build.gradle

@@ -0,0 +1,13 @@
+package com.example.swift;
+
+import org.swift.swiftkit.SwiftKit;
+
+public class JExtractPluginSampleMain {
+    public static void main() {
+        System.out.println("java.library.path = " + SwiftKit.getJavaLibraryPath());
+        System.out.println("jextract.trace.downcalls = " + SwiftKit.getJextractTraceDowncalls());
+
+        var o = new MyCoolSwiftClass(12);
+        o.exposedToJava();
+    }
+}

Samples/JExtractPluginSampleApp/src/main/java/com/example/swift/JExtractPluginSampleMain.java

@@ -56,6 +56,10 @@ sourceSets {
     }
 }
 
+tasks.build {
+    dependsOn("jextract")
+}
+
 dependencies {
     implementation(project(':SwiftKit'))
 

Samples/SwiftKitSampleApp/build.gradle

@@ -39,3 +39,13 @@ extension Collection {
     }
   }
 }
+
+extension Collection where Element == Int {
+  var sum: Int { 
+    var s = 0
+    for i in self {
+      s += i
+    }
+    return s
+  }
+}

Sources/JExtractSwift/Convenience/Collection+Extensions.swift

@@ -29,17 +29,15 @@ public typealias JavaPackage = String
 public struct ImportedNominalType: ImportedDecl {
   public let swiftTypeName: String
   public let javaType: JavaType
-  public var swiftMangledName: String?
   public var kind: NominalTypeKind
 
   public var initializers: [ImportedFunc] = []
   public var methods: [ImportedFunc] = []
   public var variables: [ImportedVariable] = []
 
-  public init(swiftTypeName: String, javaType: JavaType, swiftMangledName: String? = nil, kind: NominalTypeKind) {
+  public init(swiftTypeName: String, javaType: JavaType, kind: NominalTypeKind) {
     self.swiftTypeName = swiftTypeName
     self.javaType = javaType
-    self.swiftMangledName = swiftMangledName
     self.kind = kind
   }
 
@@ -201,16 +199,22 @@ public struct ImportedFunc: ImportedDecl, CustomStringConvertible {
 
   public var swiftMangledName: String = ""
 
-  public var syntax: String? = nil
+  public var swiftDecl: any DeclSyntaxProtocol
+
+  public var syntax: String? {
+    "\(self.swiftDecl)"
+  }
 
   public var isInit: Bool = false
 
   public init(
+    decl: any DeclSyntaxProtocol,
     parentName: TranslatedType?,
     identifier: String,
     returnType: TranslatedType,
     parameters: [ImportedParam]
   ) {
+    self.swiftDecl = decl
     self.parentName = parentName
     self.identifier = identifier
     self.returnType = returnType
@@ -287,6 +291,7 @@ public struct ImportedVariable: ImportedDecl, CustomStringConvertible {
     case .set:
       let newValueParam: FunctionParameterSyntax = "_ newValue: \(self.returnType.cCompatibleSwiftType)"
       var funcDecl = ImportedFunc(
+        decl: self.syntax!,
         parentName: self.parentName,
         identifier: self.identifier,
         returnType: TranslatedType.void,
@@ -296,6 +301,7 @@ public struct ImportedVariable: ImportedDecl, CustomStringConvertible {
 
     case .get:
       var funcDecl = ImportedFunc(
+        decl: self.syntax!,
         parentName: self.parentName,
         identifier: self.identifier,
         returnType: self.returnType,

Sources/JExtractSwift/ImportedDecls.swift

@@ -28,43 +28,64 @@ public struct SwiftToJava: ParsableCommand {
   @Option(help: "The package the generated Java code should be emitted into.")
   var packageName: String
 
-  @Option(name: .shortAndLong, help: "The directory in which to output the generated Swift files and manifest.")
-  var outputDirectory: String = ".build/jextract-swift/generated"
+  @Option(
+    name: .shortAndLong,
+    help: "The directory in which to output the generated Swift files and manifest.")
+  var outputDirectoryJava: String = ".build/jextract-swift/generated"
 
-  @Option(name: .long, help: "Name of the Swift module to import (and the swift interface files belong to)")
+  @Option(help: "Swift output directory")
+  var outputDirectorySwift: String
+
+  @Option(
+    name: .long,
+    help: "Name of the Swift module to import (and the swift interface files belong to)")
   var swiftModule: String
 
   // TODO: Once we ship this, make this `.warning` by default
   @Option(name: .shortAndLong, help: "Configure the level of lots that should be printed")
   var logLevel: Logger.Level = .notice
 
-  @Argument(help: "The Swift interface files to export to Java.")
-  var swiftInterfaceFiles: [String]
+  @Argument(help: "The Swift files or directories to recursively export to Java.")
+  var input: [String]
 
   public func run() throws {
-    let interfaceFiles = self.swiftInterfaceFiles.dropFirst()
-    print("Interface files: \(interfaceFiles)")
+    let inputPaths = self.input.dropFirst().map { URL(string: $0)! }
+    print("Input \(inputPaths)")
 
     let translator = Swift2JavaTranslator(
       javaPackage: packageName,
       swiftModuleName: swiftModule
     )
     translator.log.logLevel = logLevel
 
-    var fileNo = 1
-    for interfaceFile in interfaceFiles {
-      print("[\(fileNo)/\(interfaceFiles.count)] Importing module '\(swiftModule)', interface file: \(interfaceFile)")
-      defer { fileNo += 1 }
+    var allFiles: [URL] = []
+    let fileManager = FileManager.default
+
+    for path in inputPaths {
+      if isDirectory(url: path) {
+        if let enumerator = fileManager.enumerator(at: path, includingPropertiesForKeys: nil) {
+          for case let fileURL as URL in enumerator {
+            allFiles.append(fileURL)
+          }
+        }
+      } else if path.isFileURL {
+        allFiles.append(path)
+      }
+    }
+
+    for file in allFiles {
+      print("Importing module '\(swiftModule)', interface file: \(file)")
 
-      try translator.analyze(swiftInterfacePath: interfaceFile)
-      try translator.writeImportedTypesTo(outputDirectory: outputDirectory)
+      try translator.analyze(file: file.path)
+      try translator.writeExportedJavaSources(outputDirectory: outputDirectoryJava)
+      try translator.writeSwiftThunkSources(outputDirectory: outputDirectorySwift)
 
-      print("[\(fileNo)/\(interfaceFiles.count)] Imported interface file: \(interfaceFile) " + "done.".green)
+      print("Imported interface file: \(file) " + "done.".green)
     }
 
-    try translator.writeModuleTo(outputDirectory: outputDirectory)
+    try translator.writeExportedJavaModule(outputDirectory: outputDirectoryJava)
     print("")
-    print("Generated Java sources in package '\(packageName)' in: \(outputDirectory)/")
+    print("Generated Java sources in package '\(packageName)' in: \(outputDirectoryJava)/")
     print("Swift module '\(swiftModule)' import: " + "done.".green)
   }
 
@@ -79,3 +100,9 @@ extension Logger.Level: ExpressibleByArgument {
 
   public private(set) static var defaultCompletionKind: CompletionKind = .default
 }
+
+func isDirectory(url: URL) -> Bool {
+  var isDirectory: ObjCBool = false
+  FileManager.default.fileExists(atPath: url.path, isDirectory: &isDirectory)
+  return isDirectory.boolValue
+}