refa: jni (#2244)

* refa: jni

* refa: jni

tool/README.md

@@ -0,0 +1 @@
+run `dart run tool/jnigen.dart`

tool/jnigen.dart

@@ -0,0 +1,23 @@
+import 'dart:io' show Platform;
+
+import 'package:jnigen/jnigen.dart';
+
+void main(List<String> args) {
+  final packageRoot = Platform.script.resolve('../');
+  generateJniBindings(
+    Config(
+      outputConfig: OutputConfig(
+        dartConfig: DartCodeOutputConfig(
+          path: packageRoot.resolve('lib/utils/android/bindings.g.dart'),
+          structure: .singleFile,
+        ),
+      ),
+      androidSdkConfig: AndroidSdkConfig(addGradleDeps: true),
+      sourcePath: [packageRoot.resolve('android/app/src/main/java')],
+      classes: [
+        'com.example.piliplus',
+        'java.lang.Runnable',
+      ],
+    ),
+  );
+}