3 files changed, 26 insertions, 41 deletions
diff --git a/Source/Android/jni/AndroidCommon/IDCache.cpp b/Source/Android/jni/AndroidCommon/IDCache.cpp
index 71e2ae9d59..19b7147ba4 100644
--- a/Source/Android/jni/AndroidCommon/IDCache.cpp
+++ b/Source/Android/jni/AndroidCommon/IDCache.cpp
@@ -29,9 +29,27 @@ static jmethodID s_do_rumble;
 
 namespace IDCache
 {
-JavaVM* GetJavaVM()
-{
-  return s_java_vm;
+JNIEnv* GetEnvForThread()
+{
+  thread_local static struct OwnedEnv
+  {
+    OwnedEnv()
+    {
+      status = s_java_vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6);
+      if (status == JNI_EDETACHED)
+        s_java_vm->AttachCurrentThread(&env, nullptr);
+    }
+
+    ~OwnedEnv()
+    {
+      if (status == JNI_EDETACHED)
+        s_java_vm->DetachCurrentThread();
+    }
+
+    int status;
+    JNIEnv* env = nullptr;
+  } owned;
+  return owned.env;
 }
 
 jclass GetNativeLibraryClass()
diff --git a/Source/Android/jni/AndroidCommon/IDCache.h b/Source/Android/jni/AndroidCommon/IDCache.h
index 0e71a6ca7a..e3ef7259c1 100644
--- a/Source/Android/jni/AndroidCommon/IDCache.h
+++ b/Source/Android/jni/AndroidCommon/IDCache.h
@@ -10,7 +10,7 @@ namespace IDCache
 {
 static constexpr jint JNI_VERSION = JNI_VERSION_1_6;
 
-JavaVM* GetJavaVM();
+JNIEnv* GetEnvForThread();
 
 jclass GetNativeLibraryClass();
 jmethodID GetDisplayAlertMsg();
diff --git a/Source/Android/jni/MainAndroid.cpp b/Source/Android/jni/MainAndroid.cpp
index 763ecd182f..e0f305693b 100644
--- a/Source/Android/jni/MainAndroid.cpp
+++ b/Source/Android/jni/MainAndroid.cpp
@@ -76,17 +76,8 @@ bool s_have_wm_user_stop = false;
 void UpdatePointer()
 {
   // Update touch pointer
-  JNIEnv* env;
-  int get_env_status =
-      IDCache::GetJavaVM()->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6);
-
-  if (get_env_status == JNI_EDETACHED)
-    IDCache::GetJavaVM()->AttachCurrentThread(&env, nullptr);
-
+  JNIEnv* env = IDCache::GetEnvForThread();
   env->CallStaticVoidMethod(IDCache::GetNativeLibraryClass(), IDCache::GetUpdateTouchPointer());
-
-  if (get_env_status == JNI_EDETACHED)
-    IDCache::GetJavaVM()->DetachCurrentThread();
 }
 
 void Host_NotifyMapLoaded()
@@ -162,28 +153,19 @@ void Host_TitleChanged()
 
 static bool MsgAlert(const char* caption, const char* text, bool yes_no, MsgType /*style*/)
 {
-  __android_log_print(ANDROID_LOG_ERROR, DOLPHIN_TAG, "%s:%s", caption, text);
-
-  // Associate the current Thread with the Java VM.
-  JNIEnv* env;
-  IDCache::GetJavaVM()->AttachCurrentThread(&env, nullptr);
+  JNIEnv* env = IDCache::GetEnvForThread();
 
   // Execute the Java method.
   jboolean result = env->CallStaticBooleanMethod(
       IDCache::GetNativeLibraryClass(), IDCache::GetDisplayAlertMsg(), ToJString(env, caption),
       ToJString(env, text), yes_no ? JNI_TRUE : JNI_FALSE);
 
-  // Must be called before the current thread exits; might as well do it here.
-  IDCache::GetJavaVM()->DetachCurrentThread();
-
   return result != JNI_FALSE;
 }
 
 static void ReportSend(std::string endpoint, std::string report)
 {
-  // Associate the current Thread with the Java VM.
-  JNIEnv* env;
-  IDCache::GetJavaVM()->AttachCurrentThread(&env, nullptr);
+  JNIEnv* env = IDCache::GetEnvForThread();
 
   jbyteArray output_array = env->NewByteArray(report.size());
   jbyte* output = env->GetByteArrayElements(output_array, nullptr);
@@ -191,32 +173,17 @@ static void ReportSend(std::string endpoint, std::string report)
   env->ReleaseByteArrayElements(output_array, output, 0);
   env->CallStaticVoidMethod(IDCache::GetAnalyticsClass(), IDCache::GetSendAnalyticsReport(),
                             ToJString(env, endpoint), output_array);
-
-  IDCache::GetJavaVM()->DetachCurrentThread();
 }
 
 static std::string GetAnalyticValue(std::string key)
 {
-  // Associate the current Thread with the Java VM.
-  JNIEnv* env;
-  bool attached = false;
-  int getEnvStat =
-      IDCache::GetJavaVM()->GetEnv(reinterpret_cast<void**>(&env), IDCache::JNI_VERSION);
-  if (getEnvStat == JNI_EDETACHED)
-  {
-    IDCache::GetJavaVM()->AttachCurrentThread(&env, nullptr);
-    attached = true;
-  }
+  JNIEnv* env = IDCache::GetEnvForThread();
 
   jstring value = reinterpret_cast<jstring>(env->CallStaticObjectMethod(
       IDCache::GetAnalyticsClass(), IDCache::GetAnalyticsValue(), ToJString(env, key)));
 
   std::string stdvalue = GetJString(env, value);
 
-  // Only detach the thread if it wasn't already attached
-  if (attached)
-    IDCache::GetJavaVM()->DetachCurrentThread();
-
   return stdvalue;
 }