Migrate orderfile to RegisterNatives.

Author: Dan Albert

orderfile/app/build.gradle

@@ -26,11 +26,13 @@ android {
     }
 
     buildFeatures {
+        prefab true
         viewBinding true
     }
 }
 
 dependencies {
+    implementation project(":base")
     implementation libs.appcompat
     implementation libs.material
     implementation libs.androidx.constraintlayout

orderfile/app/src/main/cpp/CMakeLists.txt

@@ -2,6 +2,7 @@ cmake_minimum_required(VERSION 3.22.1)
 project(OrderfileDemo CXX)
 
 include(AppLibrary)
+find_package(base CONFIG REQUIRED)
 
 # We have setup build variables that you can just comment or uncomment to use.
 # Make sure to have only one build variable uncommented at a time.
@@ -13,7 +14,7 @@ set(GENERATE_PROFILES ON)
 #set(USE_PROFILE "${CMAKE_SOURCE_DIR}/demo.orderfile")
 
 add_app_library(orderfiledemo SHARED orderfile.cpp)
-target_link_libraries(orderfiledemo log)
+target_link_libraries(orderfiledemo PRIVATE base::base log)
 
 if(GENERATE_PROFILES)
     # Generating profiles requires any optimization flag aside from -O0.

orderfile/app/src/main/cpp/orderfile.cpp

@@ -1,4 +1,5 @@
 #include <android/log.h>
+#include <base/macros.h>
 #include <errno.h>
 #include <jni.h>
 #include <linux/limits.h>
@@ -46,9 +47,26 @@ void DumpProfileDataIfNeeded(const char* temp_dir) {
 #endif
 }
 
-extern "C" JNIEXPORT void JNICALL
-Java_com_example_orderfiledemo_MainActivity_runWorkload(JNIEnv* env,
-                                                        jobject /* this */,
-                                                        jstring temp_dir) {
+void RunWorkload(JNIEnv* env, jobject /* this */, jstring temp_dir) {
   DumpProfileDataIfNeeded(env->GetStringUTFChars(temp_dir, 0));
 }
+
+extern "C" JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM* _Nonnull vm,
+                                             void* _Nullable) {
+  JNIEnv* env;
+  if (vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6) != JNI_OK) {
+    return JNI_ERR;
+  }
+
+  jclass c = env->FindClass("com/example/orderfiledemo/MainActivity");
+  if (c == nullptr) return JNI_ERR;
+
+  static const JNINativeMethod methods[] = {
+      {"runWorkload", "(Ljava/lang/String;)V",
+       reinterpret_cast<void*>(RunWorkload)},
+  };
+  int rc = env->RegisterNatives(c, methods, arraysize(methods));
+  if (rc != JNI_OK) return rc;
+
+  return JNI_VERSION_1_6;
+}