extend jextract build plugin to compile java sources

Author: madsodgaard

Plugins/JExtractSwiftPlugin/JExtractSwiftPlugin.swift

@@ -25,9 +25,16 @@ struct JExtractSwiftBuildToolPlugin: SwiftJavaPluginProtocol, BuildToolPlugin {
 
   func createBuildCommands(context: PluginContext, target: Target) throws -> [Command] {
     let toolURL = try context.tool(named: "SwiftJavaTool").url
-    
+
+    // The URL of the compiled Java sources
+    let javaClassFileURL = context.pluginWorkDirectoryURL
+      .appending(path: "compiled-java-output")
+
+    var commands: [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.
     for dependency in target.dependencies {
@@ -123,15 +130,71 @@ struct JExtractSwiftBuildToolPlugin: SwiftJavaPluginProtocol, BuildToolPlugin {
 
     print("[swift-java-plugin] Output swift files:\n - \(outputSwiftFiles.map({$0.absoluteString}).joined(separator: "\n - "))")
 
-    return [
+    // Extract list of all sources
+    let javaSourcesFile = outputJavaDirectory.appending(path: "sources.txt")
+
+    commands += [
       .buildCommand(
         displayName: "Generate Java wrappers for Swift types",
         executable: toolURL,
         arguments: arguments,
         inputFiles: [ configFile ] + swiftFiles,
-        outputFiles: outputSwiftFiles
+        outputFiles: outputSwiftFiles + [javaSourcesFile]
       )
     ]
+
+    // Build SwiftKitCore and get the classpath
+    // as the jextracted sources will depend on that
+
+    guard let swiftJavaDirectory = findSwiftJavaDirectory(for: target) else {
+      // FIXME: Error
+      fatalError()
+    }
+    log("Found swift-java at \(swiftJavaDirectory)")
+
+    commands += [
+      .buildCommand(
+        displayName: "Build SwiftKitCore",
+        executable: swiftJavaDirectory.appending(path: "gradlew"),
+        arguments: [
+          ":SwiftKitCore:build",
+          "-p", swiftJavaDirectory.path(percentEncoded: false),
+          "--configure-on-demand",
+          "--no-daemon"
+        ],
+        environment: [:],
+        inputFiles: [swiftJavaDirectory],
+        outputFiles: []
+      )
+    ]
+
+    let swiftKitCoreClassPath = swiftJavaDirectory.appending(path: "SwiftKitCore/build/classes/java/main")
+
+    // Compile the jextracted sources
+    let javaHome = URL(filePath: findJavaHome())
+  #if os(Windows)
+    let javac = "javac.exe"
+  #else
+    let javac = "javac"
+  #endif
+    commands += [
+      .buildCommand(
+        displayName: "Build extracted Java sources",
+        executable: javaHome
+          .appending(path: "bin")
+          .appending(path: javac),
+        arguments: [
+          "@\(javaSourcesFile.path(percentEncoded: false))",
+          "-d", javaClassFileURL.path,
+          "-parameters",
+          "-classpath", swiftKitCoreClassPath.path(percentEncoded: false)
+        ],
+        inputFiles: [javaSourcesFile],
+        outputFiles: []
+      )
+    ]
+
+    return commands
   }
 
   /// Find the manifest files from other swift-java executions in any targets
@@ -181,5 +244,27 @@ struct JExtractSwiftBuildToolPlugin: SwiftJavaPluginProtocol, BuildToolPlugin {
 
     return dependentConfigFiles
   }
+
+  private func findSwiftJavaDirectory(for target: any Target) -> URL? {
+    for dependency in target.dependencies {
+      switch dependency {
+      case .target(let target):
+        continue
+
+      case .product(let product):
+        guard let swiftJava = product.sourceModules.first(where: { $0.name == "SwiftJava" }) else {
+          return nil
+        }
+
+        // We are inside Sources/SwiftJava
+        return swiftJava.directoryURL.deletingLastPathComponent().deletingLastPathComponent()
+
+      @unknown default:
+        continue
+      }
+    }
+
+    return nil
+  }
 }
 

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator+JavaBindingsPrinting.swift

@@ -12,6 +12,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+import Foundation
 import JavaTypes
 
 // MARK: Defaults
@@ -40,6 +41,8 @@ extension JNISwift2JavaGenerator {
   package func writeExportedJavaSources(_ printer: inout CodePrinter) throws {
     let importedTypes = analysis.importedTypes.sorted(by: { (lhs, rhs) in lhs.key < rhs.key })
 
+    var exportedFileNames: Set<String> = []
+
     // Each parent type goes into its own file
     // any nested types are printed inside the body as `static class`
     for (_, ty) in importedTypes.filter({ _, type in type.parent == nil }) {
@@ -52,6 +55,7 @@ extension JNISwift2JavaGenerator {
         javaPackagePath: javaPackagePath,
         filename: filename
       ) {
+        exportedFileNames.insert(outputFile.path(percentEncoded: false))
         logger.info("[swift-java] Generated: \(ty.swiftNominal.name.bold).java (at \(outputFile))")
       }
     }
@@ -65,10 +69,24 @@ extension JNISwift2JavaGenerator {
       javaPackagePath: javaPackagePath,
       filename: filename
     ) {
+      exportedFileNames.insert(outputFile.path(percentEncoded: false))
       logger.info("[swift-java] Generated: \(self.swiftModuleName).java (at \(outputFile))")
     }
+
+    // Write sources.txt file
+    if !exportedFileNames.isEmpty {
+      let outputPath = URL(fileURLWithPath: javaOutputDirectory).appending(path: "sources.txt")
+      try exportedFileNames.joined(separator: "\n").write(
+        to: outputPath,
+        atomically: true,
+        encoding: .utf8
+      )
+      logger.info("Generated file at \(outputPath)")
+    }
   }
 
+
+
   private func printModule(_ printer: inout CodePrinter) {
     printHeader(&printer)
     printPackage(&printer)