Put JNI functions under an interface

ci/licenses_golden/licenses_flutter

@@ -784,13 +784,15 @@ FILE: ../../../flutter/shell/platform/android/io/flutter/view/FlutterRunArgument
 FILE: ../../../flutter/shell/platform/android/io/flutter/view/FlutterView.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/view/TextureRegistry.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/view/VsyncWaiter.java
+FILE: ../../../flutter/shell/platform/android/jni/platform_view_android_jni.cc
+FILE: ../../../flutter/shell/platform/android/jni/platform_view_android_jni.h
 FILE: ../../../flutter/shell/platform/android/library_loader.cc
 FILE: ../../../flutter/shell/platform/android/platform_message_response_android.cc
 FILE: ../../../flutter/shell/platform/android/platform_message_response_android.h
 FILE: ../../../flutter/shell/platform/android/platform_view_android.cc
 FILE: ../../../flutter/shell/platform/android/platform_view_android.h
-FILE: ../../../flutter/shell/platform/android/platform_view_android_jni.cc
-FILE: ../../../flutter/shell/platform/android/platform_view_android_jni.h
+FILE: ../../../flutter/shell/platform/android/platform_view_android_jni_impl.cc
+FILE: ../../../flutter/shell/platform/android/platform_view_android_jni_impl.h
 FILE: ../../../flutter/shell/platform/android/robolectric.properties
 FILE: ../../../flutter/shell/platform/android/vsync_waiter_android.cc
 FILE: ../../../flutter/shell/platform/android/vsync_waiter_android.h

shell/platform/android/BUILD.gn

@@ -50,8 +50,8 @@ shared_library("flutter_shell_native") {
     "platform_message_response_android.h",
     "platform_view_android.cc",
     "platform_view_android.h",
-    "platform_view_android_jni.cc",
-    "platform_view_android_jni.h",
+    "platform_view_android_jni_impl.cc",
+    "platform_view_android_jni_impl.h",
     "vsync_waiter_android.cc",
     "vsync_waiter_android.h",
   ]
@@ -68,6 +68,7 @@ shared_library("flutter_shell_native") {
     "//flutter/runtime:libdart",
     "//flutter/shell/common",
     "//flutter/shell/platform/android/external_view_embedder",
+    "//flutter/shell/platform/android/jni",
     "//third_party/skia",
   ]
 

shell/platform/android/android_external_texture_gl.cc

@@ -6,15 +6,18 @@
 
 #include <GLES/glext.h>
 
-#include "flutter/shell/platform/android/platform_view_android_jni.h"
 #include "third_party/skia/include/gpu/GrBackendSurface.h"
 
 namespace flutter {
 
 AndroidExternalTextureGL::AndroidExternalTextureGL(
     int64_t id,
-    const fml::jni::JavaObjectWeakGlobalRef& surfaceTexture)
-    : Texture(id), surface_texture_(surfaceTexture), transform(SkMatrix::I()) {}
+    const fml::jni::JavaObjectWeakGlobalRef& surface_texture,
+    std::unique_ptr<PlatformViewAndroidJNI> jni_facade)
+    : Texture(id),
+      jni_facade_(std::move(jni_facade)),
+      surface_texture_(surface_texture),
+      transform(SkMatrix::I()) {}
 
 AndroidExternalTextureGL::~AndroidExternalTextureGL() {
   if (state_ == AttachmentState::attached) {
@@ -68,36 +71,8 @@ void AndroidExternalTextureGL::Paint(SkCanvas& canvas,
   }
 }
 
-// The bounds we set for the canvas are post composition.
-// To fill the canvas we need to ensure that the transformation matrix
-// on the `SurfaceTexture` will be scaled to fill. We rescale and preseve
-// the scaled aspect ratio.
-SkSize ScaleToFill(float scaleX, float scaleY) {
-  const double epsilon = std::numeric_limits<double>::epsilon();
-  // scaleY is negative.
-  const double minScale = fmin(scaleX, fabs(scaleY));
-  const double rescale = 1.0f / (minScale + epsilon);
-  return SkSize::Make(scaleX * rescale, scaleY * rescale);
-}
-
 void AndroidExternalTextureGL::UpdateTransform() {
-  JNIEnv* env = fml::jni::AttachCurrentThread();
-  fml::jni::ScopedJavaLocalRef<jobject> surfaceTexture =
-      surface_texture_.get(env);
-  fml::jni::ScopedJavaLocalRef<jfloatArray> transformMatrix(
-      env, env->NewFloatArray(16));
-  SurfaceTextureGetTransformMatrix(env, surfaceTexture.obj(),
-                                   transformMatrix.obj());
-  float* m = env->GetFloatArrayElements(transformMatrix.obj(), nullptr);
-  float scaleX = m[0], scaleY = m[5];
-  const SkSize scaled = ScaleToFill(scaleX, scaleY);
-  SkScalar matrix3[] = {
-      scaled.fWidth, m[1],           m[2],   //
-      m[4],          scaled.fHeight, m[6],   //
-      m[8],          m[9],           m[10],  //
-  };
-  env->ReleaseFloatArrayElements(transformMatrix.obj(), m, JNI_ABORT);
-  transform.set9(matrix3);
+  jni_facade_->SurfaceTextureGetTransformMatrix(surface_texture_, transform);
 }
 
 void AndroidExternalTextureGL::OnGrContextDestroyed() {
@@ -108,31 +83,16 @@ void AndroidExternalTextureGL::OnGrContextDestroyed() {
 }
 
 void AndroidExternalTextureGL::Attach(jint textureName) {
-  JNIEnv* env = fml::jni::AttachCurrentThread();
-  fml::jni::ScopedJavaLocalRef<jobject> surfaceTexture =
-      surface_texture_.get(env);
-  if (!surfaceTexture.is_null()) {
-    SurfaceTextureAttachToGLContext(env, surfaceTexture.obj(), textureName);
-  }
+  jni_facade_->SurfaceTextureAttachToGLContext(surface_texture_, textureName);
 }
 
 void AndroidExternalTextureGL::Update() {
-  JNIEnv* env = fml::jni::AttachCurrentThread();
-  fml::jni::ScopedJavaLocalRef<jobject> surfaceTexture =
-      surface_texture_.get(env);
-  if (!surfaceTexture.is_null()) {
-    SurfaceTextureUpdateTexImage(env, surfaceTexture.obj());
-    UpdateTransform();
-  }
+  jni_facade_->SurfaceTextureUpdateTexImage(surface_texture_);
+  UpdateTransform();
 }
 
 void AndroidExternalTextureGL::Detach() {
-  JNIEnv* env = fml::jni::AttachCurrentThread();
-  fml::jni::ScopedJavaLocalRef<jobject> surfaceTexture =
-      surface_texture_.get(env);
-  if (!surfaceTexture.is_null()) {
-    SurfaceTextureDetachFromGLContext(env, surfaceTexture.obj());
-  }
+  jni_facade_->SurfaceTextureDetachFromGLContext(surface_texture_);
 }
 
 void AndroidExternalTextureGL::OnTextureUnregistered() {}

shell/platform/android/android_external_texture_gl.h

@@ -8,14 +8,16 @@
 #include <GLES/gl.h>
 #include "flutter/flow/texture.h"
 #include "flutter/fml/platform/android/jni_weak_ref.h"
+#include "flutter/shell/platform/android/platform_view_android_jni_impl.h"
 
 namespace flutter {
 
 class AndroidExternalTextureGL : public flutter::Texture {
  public:
   AndroidExternalTextureGL(
       int64_t id,
-      const fml::jni::JavaObjectWeakGlobalRef& surfaceTexture);
+      const fml::jni::JavaObjectWeakGlobalRef& surface_texture,
+      std::unique_ptr<PlatformViewAndroidJNI> jni_facade);
 
   ~AndroidExternalTextureGL() override;
 
@@ -43,6 +45,8 @@ class AndroidExternalTextureGL : public flutter::Texture {
 
   enum class AttachmentState { uninitialized, attached, detached };
 
+  std::unique_ptr<PlatformViewAndroidJNI> jni_facade_;
+
   fml::jni::JavaObjectWeakGlobalRef surface_texture_;
 
   AttachmentState state_ = AttachmentState::uninitialized;

shell/platform/android/android_shell_holder.cc

@@ -29,9 +29,9 @@ static WindowData GetDefaultWindowData() {
 
 AndroidShellHolder::AndroidShellHolder(
     flutter::Settings settings,
-    fml::jni::JavaObjectWeakGlobalRef java_object,
+    std::unique_ptr<PlatformViewAndroidJNI> jni_facade,
     bool is_background_view)
-    : settings_(std::move(settings)), java_object_(java_object) {
+    : settings_(std::move(settings)), jni_facade_(std::move(jni_facade)) {
   static size_t shell_count = 1;
   auto thread_label = std::to_string(shell_count++);
 
@@ -56,20 +56,19 @@ AndroidShellHolder::AndroidShellHolder(
 
   fml::WeakPtr<PlatformViewAndroid> weak_platform_view;
   Shell::CreateCallback<PlatformView> on_create_platform_view =
-      [is_background_view, java_object, &weak_platform_view](Shell& shell) {
+      [is_background_view, &jni_facade, &weak_platform_view](Shell& shell) {
         std::unique_ptr<PlatformViewAndroid> platform_view_android;
         if (is_background_view) {
           platform_view_android = std::make_unique<PlatformViewAndroid>(
               shell,                   // delegate
               shell.GetTaskRunners(),  // task runners
-              java_object              // java object handle for JNI interop
+              std::move(jni_facade)    // JNI interop
           );
-
         } else {
           platform_view_android = std::make_unique<PlatformViewAndroid>(
               shell,                   // delegate
               shell.GetTaskRunners(),  // task runners
-              java_object,             // java object handle for JNI interop
+              std::move(jni_facade),   // JNI interop
               shell.GetSettings()
                   .enable_software_rendering  // use software rendering
           );

shell/platform/android/android_shell_holder.h

@@ -8,21 +8,21 @@
 #include <memory>
 
 #include "flutter/fml/macros.h"
-#include "flutter/fml/platform/android/jni_weak_ref.h"
 #include "flutter/fml/unique_fd.h"
 #include "flutter/lib/ui/window/viewport_metrics.h"
 #include "flutter/runtime/window_data.h"
 #include "flutter/shell/common/run_configuration.h"
 #include "flutter/shell/common/shell.h"
 #include "flutter/shell/common/thread_host.h"
+#include "flutter/shell/platform/android/jni/platform_view_android_jni.h"
 #include "flutter/shell/platform/android/platform_view_android.h"
 
 namespace flutter {
 
 class AndroidShellHolder {
  public:
   AndroidShellHolder(flutter::Settings settings,
-                     fml::jni::JavaObjectWeakGlobalRef java_object,
+                     std::unique_ptr<PlatformViewAndroidJNI> jni_facade,
                      bool is_background_view);
 
   ~AndroidShellHolder();
@@ -42,7 +42,7 @@ class AndroidShellHolder {
 
  private:
   const flutter::Settings settings_;
-  const fml::jni::JavaObjectWeakGlobalRef java_object_;
+  const std::unique_ptr<PlatformViewAndroidJNI> jni_facade_;
   fml::WeakPtr<PlatformViewAndroid> platform_view_;
   ThreadHost thread_host_;
   std::unique_ptr<Shell> shell_;

shell/platform/android/android_surface.cc

@@ -15,18 +15,20 @@
 namespace flutter {
 
 std::unique_ptr<AndroidSurface> AndroidSurface::Create(
-    std::shared_ptr<AndroidContext> android_context) {
+    std::shared_ptr<AndroidContext> android_context,
+    std::unique_ptr<PlatformViewAndroidJNI> jni_facade) {
   std::unique_ptr<AndroidSurface> surface;
   switch (android_context->RenderingApi()) {
     case AndroidRenderingAPI::kSoftware:
-      surface = std::make_unique<AndroidSurfaceSoftware>();
+      surface = std::make_unique<AndroidSurfaceSoftware>(std::move(jni_facade));
       break;
     case AndroidRenderingAPI::kOpenGLES:
-      surface = std::make_unique<AndroidSurfaceGL>(android_context);
+      surface = std::make_unique<AndroidSurfaceGL>(android_context,
+                                                   std::move(jni_facade));
       break;
     case AndroidRenderingAPI::kVulkan:
 #if SHELL_ENABLE_VULKAN
-      surface = std::make_unique<AndroidSurfaceVulkan>();
+      surface = std::make_unique<AndroidSurfaceVulkan>(std::move(jni_facade));
 #endif  // SHELL_ENABLE_VULKAN
       break;
   }

shell/platform/android/android_surface.h

@@ -14,14 +14,16 @@
 #include "flutter/shell/common/surface.h"
 #include "flutter/shell/platform/android/android_context.h"
 #include "flutter/shell/platform/android/android_native_window.h"
+#include "flutter/shell/platform/android/jni/platform_view_android_jni.h"
 #include "third_party/skia/include/core/SkSize.h"
 
 namespace flutter {
 
 class AndroidSurface {
  public:
   static std::unique_ptr<AndroidSurface> Create(
-      std::shared_ptr<AndroidContext> android_context);
+      std::shared_ptr<AndroidContext> android_context,
+      std::unique_ptr<PlatformViewAndroidJNI> jni_facade);
 
   virtual ~AndroidSurface();
 

shell/platform/android/android_surface_gl.cc

@@ -12,7 +12,8 @@
 namespace flutter {
 
 AndroidSurfaceGL::AndroidSurfaceGL(
-    std::shared_ptr<AndroidContext> android_context)
+    std::shared_ptr<AndroidContext> android_context,
+    std::unique_ptr<PlatformViewAndroidJNI> jni_facade)
     : native_window_(nullptr),
       onscreen_surface_(nullptr),
       offscreen_surface_(nullptr) {
@@ -23,7 +24,8 @@ AndroidSurfaceGL::AndroidSurfaceGL(
   if (offscreen_surface_ == EGL_NO_SURFACE) {
     offscreen_surface_ = nullptr;
   }
-  external_view_embedder_ = std::make_unique<AndroidExternalViewEmbedder>();
+  external_view_embedder_ =
+      std::make_unique<AndroidExternalViewEmbedder>(std::move(jni_facade));
 }
 
 AndroidSurfaceGL::~AndroidSurfaceGL() {

shell/platform/android/android_surface_gl.h

@@ -14,13 +14,15 @@
 #include "flutter/shell/platform/android/android_environment_gl.h"
 #include "flutter/shell/platform/android/android_surface.h"
 #include "flutter/shell/platform/android/external_view_embedder/external_view_embedder.h"
+#include "flutter/shell/platform/android/jni/platform_view_android_jni.h"
 
 namespace flutter {
 
 class AndroidSurfaceGL final : public GPUSurfaceGLDelegate,
                                public AndroidSurface {
  public:
-  AndroidSurfaceGL(std::shared_ptr<AndroidContext> android_context);
+  AndroidSurfaceGL(std::shared_ptr<AndroidContext> android_context,
+                   std::unique_ptr<PlatformViewAndroidJNI> jni_facade);
 
   ~AndroidSurfaceGL() override;
 

shell/platform/android/android_surface_software.cc

@@ -11,7 +11,7 @@
 #include "flutter/fml/platform/android/jni_weak_ref.h"
 #include "flutter/fml/platform/android/scoped_java_ref.h"
 #include "flutter/fml/trace_event.h"
-#include "flutter/shell/platform/android/platform_view_android_jni.h"
+#include "flutter/shell/platform/android/jni/platform_view_android_jni.h"
 
 namespace flutter {
 
@@ -36,10 +36,12 @@ bool GetSkColorType(int32_t buffer_format,
 
 }  // anonymous namespace
 
-AndroidSurfaceSoftware::AndroidSurfaceSoftware() {
+AndroidSurfaceSoftware::AndroidSurfaceSoftware(
+    std::unique_ptr<PlatformViewAndroidJNI> jni_facade) {
   GetSkColorType(WINDOW_FORMAT_RGBA_8888, &target_color_type_,
                  &target_alpha_type_);
-  external_view_embedder_ = std::make_unique<AndroidExternalViewEmbedder>();
+  external_view_embedder_ =
+      std::make_unique<AndroidExternalViewEmbedder>(std::move(jni_facade));
 }
 
 AndroidSurfaceSoftware::~AndroidSurfaceSoftware() = default;

shell/platform/android/android_surface_software.h

@@ -11,13 +11,14 @@
 #include "flutter/shell/gpu/gpu_surface_software.h"
 #include "flutter/shell/platform/android/android_surface.h"
 #include "flutter/shell/platform/android/external_view_embedder/external_view_embedder.h"
+#include "flutter/shell/platform/android/jni/platform_view_android_jni.h"
 
 namespace flutter {
 
 class AndroidSurfaceSoftware final : public AndroidSurface,
                                      public GPUSurfaceSoftwareDelegate {
  public:
-  AndroidSurfaceSoftware();
+  AndroidSurfaceSoftware(std::unique_ptr<PlatformViewAndroidJNI> jni_facade);
 
   ~AndroidSurfaceSoftware() override;
 

shell/platform/android/android_surface_vulkan.cc

@@ -12,9 +12,11 @@
 
 namespace flutter {
 
-AndroidSurfaceVulkan::AndroidSurfaceVulkan()
+AndroidSurfaceVulkan::AndroidSurfaceVulkan(
+    std::unique_ptr<PlatformViewAndroidJNI> jni_facade)
     : proc_table_(fml::MakeRefCounted<vulkan::VulkanProcTable>()) {
-  external_view_embedder_ = std::make_unique<AndroidExternalViewEmbedder>();
+  external_view_embedder_ =
+      std::make_unique<AndroidExternalViewEmbedder>(std::move(jni_facade));
 }
 
 AndroidSurfaceVulkan::~AndroidSurfaceVulkan() = default;

shell/platform/android/android_surface_vulkan.h

@@ -12,14 +12,15 @@
 #include "flutter/shell/platform/android/android_native_window.h"
 #include "flutter/shell/platform/android/android_surface.h"
 #include "flutter/shell/platform/android/external_view_embedder/external_view_embedder.h"
+#include "flutter/shell/platform/android/jni/platform_view_android_jni.h"
 #include "flutter/vulkan/vulkan_window.h"
 
 namespace flutter {
 
 class AndroidSurfaceVulkan : public AndroidSurface,
                              public GPUSurfaceVulkanDelegate {
  public:
-  AndroidSurfaceVulkan();
+  AndroidSurfaceVulkan(std::unique_ptr<PlatformViewAndroidJNI> jni_facade);
 
   ~AndroidSurfaceVulkan() override;
 

shell/platform/android/external_view_embedder/BUILD.gn

@@ -22,6 +22,7 @@ source_set("external_view_embedder") {
     "//flutter/common",
     "//flutter/flow",
     "//flutter/fml",
+    "//flutter/shell/platform/android/jni",
     "//third_party/skia",
   ]
 }

shell/platform/android/external_view_embedder/external_view_embedder.cc

@@ -8,6 +8,10 @@
 
 namespace flutter {
 
+AndroidExternalViewEmbedder::AndroidExternalViewEmbedder(
+    std::unique_ptr<PlatformViewAndroidJNI> jni_facade)
+    : ExternalViewEmbedder(), jni_facade_(std::move(jni_facade)) {}
+
 // |ExternalViewEmbedder|
 void AndroidExternalViewEmbedder::PrerollCompositeEmbeddedView(
     int view_id,