android_jni: Do not populate fieldIDs on JNI_OnLoad
Populate the fieldIDs only when the function is used. This way if
the java class variables are not found for some reason (like
proguard optimization), it will raise an exception only when the
function is invoked (and not when the library is loaded).
GOOGLE_INTERNAL_CL: 525239551
diff --git a/android_jni/avifandroidjni/src/main/jni/libavif_jni.cc b/android_jni/avifandroidjni/src/main/jni/libavif_jni.cc
index ef9d69d..efaef2d 100644
--- a/android_jni/avifandroidjni/src/main/jni/libavif_jni.cc
+++ b/android_jni/avifandroidjni/src/main/jni/libavif_jni.cc
@@ -25,17 +25,6 @@
namespace {
-jfieldID global_info_width;
-jfieldID global_info_height;
-jfieldID global_info_depth;
-jfieldID global_info_alpha_present;
-jfieldID global_width;
-jfieldID global_height;
-jfieldID global_depth;
-jfieldID global_frame_count;
-jfieldID global_repetition_count;
-jfieldID global_frame_durations;
-
// RAII wrapper class that properly frees the decoder related objects on
// destruction.
struct AvifDecoderWrapper {
@@ -155,22 +144,6 @@
if (vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6) != JNI_OK) {
return -1;
}
- const jclass info_class =
- env->FindClass("org/aomedia/avif/android/AvifDecoder$Info");
- global_info_width = env->GetFieldID(info_class, "width", "I");
- global_info_height = env->GetFieldID(info_class, "height", "I");
- global_info_depth = env->GetFieldID(info_class, "depth", "I");
- global_info_alpha_present = env->GetFieldID(info_class, "alphaPresent", "Z");
- const jclass avif_decoder_class =
- env->FindClass("org/aomedia/avif/android/AvifDecoder");
- global_width = env->GetFieldID(avif_decoder_class, "width", "I");
- global_height = env->GetFieldID(avif_decoder_class, "height", "I");
- global_depth = env->GetFieldID(avif_decoder_class, "depth", "I");
- global_frame_count = env->GetFieldID(avif_decoder_class, "frameCount", "I");
- global_repetition_count =
- env->GetFieldID(avif_decoder_class, "repetitionCount", "I");
- global_frame_durations =
- env->GetFieldID(avif_decoder_class, "frameDurations", "[D");
return JNI_VERSION_1_6;
}
@@ -188,11 +161,17 @@
if (!CreateDecoderAndParse(&decoder, buffer, length, /*threads=*/1)) {
return false;
}
- env->SetIntField(info, global_info_width, decoder.decoder->image->width);
- env->SetIntField(info, global_info_height, decoder.decoder->image->height);
- env->SetIntField(info, global_info_depth, decoder.decoder->image->depth);
- env->SetBooleanField(info, global_info_alpha_present,
- decoder.decoder->alphaPresent);
+ const jclass info_class =
+ env->FindClass("org/aomedia/avif/android/AvifDecoder$Info");
+ const jfieldID width = env->GetFieldID(info_class, "width", "I");
+ const jfieldID height = env->GetFieldID(info_class, "height", "I");
+ const jfieldID depth = env->GetFieldID(info_class, "depth", "I");
+ const jfieldID alpha_present =
+ env->GetFieldID(info_class, "alphaPresent", "Z");
+ env->SetIntField(info, width, decoder.decoder->image->width);
+ env->SetIntField(info, height, decoder.decoder->image->height);
+ env->SetIntField(info, depth, decoder.decoder->image->depth);
+ env->SetBooleanField(info, alpha_present, decoder.decoder->alphaPresent);
return true;
}
@@ -225,13 +204,24 @@
if (!CreateDecoderAndParse(decoder.get(), buffer, length, /*threads=*/1)) {
return 0;
}
- env->SetIntField(thiz, global_width, decoder->decoder->image->width);
- env->SetIntField(thiz, global_height, decoder->decoder->image->height);
- env->SetIntField(thiz, global_depth, decoder->decoder->image->depth);
- env->SetIntField(thiz, global_repetition_count,
+ const jclass avif_decoder_class =
+ env->FindClass("org/aomedia/avif/android/AvifDecoder");
+ const jfieldID width_id = env->GetFieldID(avif_decoder_class, "width", "I");
+ const jfieldID height_id = env->GetFieldID(avif_decoder_class, "height", "I");
+ const jfieldID depth_id = env->GetFieldID(avif_decoder_class, "depth", "I");
+ const jfieldID frame_count_id =
+ env->GetFieldID(avif_decoder_class, "frameCount", "I");
+ const jfieldID repetition_count_id =
+ env->GetFieldID(avif_decoder_class, "repetitionCount", "I");
+ const jfieldID frame_durations_id =
+ env->GetFieldID(avif_decoder_class, "frameDurations", "[D");
+ env->SetIntField(thiz, width_id, decoder->decoder->image->width);
+ env->SetIntField(thiz, height_id, decoder->decoder->image->height);
+ env->SetIntField(thiz, depth_id, decoder->decoder->image->depth);
+ env->SetIntField(thiz, repetition_count_id,
decoder->decoder->repetitionCount);
const int frameCount = decoder->decoder->imageCount;
- env->SetIntField(thiz, global_frame_count, frameCount);
+ env->SetIntField(thiz, frame_count_id, frameCount);
// This native array is needed because setting one element at a time to a Java
// array from the JNI layer is inefficient.
std::unique_ptr<double[]> native_durations(
@@ -253,7 +243,7 @@
}
env->SetDoubleArrayRegion(durations, /*start=*/0, frameCount,
native_durations.get());
- env->SetObjectField(thiz, global_frame_durations, durations);
+ env->SetObjectField(thiz, frame_durations_id, durations);
return reinterpret_cast<jlong>(decoder.release());
}
