Android, can't use library

[NickRadu]

How I can use this library in Android oS?

I got following exception:
java.lang.UnsatisfiedLinkError: No native resource found at /android-armv7l/libh3-java.so
at com.uber.h3core.H3CoreLoader.copyResource(H3CoreLoader.java:67)
at com.uber.h3core.H3CoreLoader.loadNatives(H3CoreLoader.java:99)
at com.uber.h3core.H3Core.newInstance(H3Core.java:68)

Thank you.

[isaacbrodsky]

Hi, thanks for reporting this.

I believe this is an issue with how the library is trying to detect what architecture of native library to use. It tries to use what it got from the system property os.arch, which was armv7l, when the resource path expects arm. For x86 we have a bunch of aliases in H3CoreLoader to handle this kind of situation.

We should add some aliases in H3CoreLoader to handle common architecture names on Android. We should probably also expose an API for the user to specify the OS/architecture to use in case the automatic detection doesn't get it right.

[NickRadu]

Hi Isaac and thanks for your response.

I see, but I don;t want to build the h3-Java library at least for now to add aliases in H3CoreLoader.
After I unpacked my apk I noticed that there;s no android directory with h3 library, I can see only:
darwin-x64, windows-x64, windows-x86 folders, it's ok?

Also I tried using newSystemInstance() method that loads library directly and I get another exception:
"java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "lround" referenced by "/data/app/com.myapp-1/lib/arm/libh3-java.so".

Thanks.

[isaacbrodsky]

@NickRadu that doesn't sound right - what version of h3-java are you using? Could you try 3.0.4? There should be a directory android-arm which should have the library for armv7l.

[NickRadu]

@ isaacbrodsky I'm using already version 3.0.4.
implementation 'com.uber:h3:3.0.4'
Thanks.

[isaacbrodsky]

I experimented with a test Android app, and was able to get it working with newSystemInstance and modifying H3-Java a little.

I faced an issue like you mention where only the windows-x64 and windows-x86 native libraries are copied into the APK (I didn't get darwin-x64 copied.) Without repackaging H3-Java as an Android library, I was only able to work around that by using the jniLibs feature (place the library at src/main/jniLibs/arm64-v8a/libh3-java.so in my case.) I also added splits { abi { enable false } } to the android section of my app's build.gradle.

Unfortunately this did not work as loading the library failed with an exception very similar to yours: java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "tan" referenced by .... This looks like the library was unable to load libm. I changed the H3-Java build script to link to libm, using the same pattern as H3 in CMakeLists.txt. This allowed me to load H3 into an Android app.

I'll update my PR with the change to link to libm, and a couple fixes for accessibility (especially of H3CoreLoader.) In the future, we might want to package an H3-Java specifically for Android, which might help with the need to copy the native library into your project.

[NickRadu]

Hi Isaac,

Great news, thank you for help. Do you have any ETA for this fix?

Thank.

[isaacbrodsky]

Hi, the fix for libm should be included in the v3.1.0 of the H3-Java library.

[NickRadu]

Hi Isaac, thanks for the fix.

[yterletskyi]

I'm using version 3.2.0 and still getting UnsatisfiedLinkError with couldn't find "libh3-java.so". Could you please help me to run it?

[isaacbrodsky]

Hi, I think the missing part is the native library resource being copied into the Android application. I'll leave this issue reopened to track that.

Could you try the above steps of copying the native library files into the jniLibs folder for your project (so they get included in the built APK)?

[yterletskyi]

where do I find libh3-java.so please?

[isaacbrodsky]

@yterletskyi You can find the resource files android-arm/libh3-java.so and android-arm64/libh3-java.soinside the downloadedh3-3.2.0.jar` file.

[long1eu]

any updates on this?

[long1eu]

I've added them to my jniLibs but still UnsatisfiedLinkError

[long1eu]

This is how I call it.

[isaacbrodsky]

Hi, I don't have an update on packaging the library for Android. Could you check if the files are copied to the APK? I needed to add specific build option (splits { abi { enable false } } in android in build.gradle) to get the libraries packaged in.

[MaGoOoDy]

i am still having the same issue :
java.lang.UnsatisfiedLinkError: No native resource found at /android-x86/libh3-java.so

i will post some photos

[isaacbrodsky]

The cross compiling system we use (Dockcross) doesn't seem to offer an android-x86 option, so I assume we do not currently support that. Could you try running on ARM with the workaround posted above regarding copying the so files and setting the splits ... option?

[lkoelman]

I still get the error java.lang.UnsatisfiedLinkError: No native resource found at /android-arm64/libh3-java.so running on ARM even when applying the listed fixes (manually copying .so files, adding the splits { ... } option). I'm using Android studio 3.4 and Gradle 5.4

[lkoelman]

Solved by using H3Core.newSystemInstance() instead of H3Core.newInstance()

[MaGoOoDy]

The cross compiling system we use (Dockcross) doesn't seem to offer an android-x86 option, so I assume we do not currently support that. Could you try running on ARM with the workaround posted above regarding copying the so files and setting the splits ... option?

i have copied the whole library folder to jinLibs folder and added the splits option to my gradle file, but when i run the emulator it took to much time to install the app then an error should up Session 'app': Install failed. The device timed out while trying to install the application. Rerun

do i need to reference something in local.properties file ?
do i need to load the library in the Activity ?

[AmaroNeto]

Hi everybody,
Some update? I'm trying use H3 in android and still show this error: java.lang.UnsatisfiedLinkError: No native resource found at /android-arm64/libh3-java.so.

I'm already added android-arm64/libh3-java.so in jniLib and didn't work.

[alphanota]

I also came across this issue. I was able to manually load the *.so by adding the jniLibs folder and adding splits {... } to the build.gradle folder as suggested.

Then I set a breakpoint on line 67 in H3CoreLoader.java

            if (resource == null) {

After starting the app in debug mode, the breakpoint is hit and the debug console appears. I had to set the resource variable as:

H3CoreLoader.class.getClassLoader().getResourceAsStream("lib/android-arm64/libh3-java.so")

Where android-arm64/ is the folder that was copied and pasted from the jar into the jniLibs folder

This is all on Android Studio

[yelsane]

Hi everybody,
Some update? I'm trying use H3 in android and still show this error: java.lang.UnsatisfiedLinkError: No native resource found at /android-arm64/libh3-java.so.

I'm already added android-arm64/libh3-java.so in jniLib and didn't work.

Rename your android-arm64 to just arm64.

I just managed to make the library work on my end myself. I added a StackOverflow answer here:
Android h3: A Hexagonal Hierarchical Geospatial Indexing System

Here's a sample project

[tijanja]

java.lang.UnsatisfiedLinkError: dalvik.system.PathClassLoader[DexPathList[[zip file "/system/framework/org.apache.http.legacy.boot.jar", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/base.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_dependencies_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_resources_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_0_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_1_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_2_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_3_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_4_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_5_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_6_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_7_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_8_apk.apk", zip file "/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/split_lib_slice_9_apk.apk"],nativeLibraryDirectories=[/data/app/buhari.teetech.com.dinkkydriver-j2qNhxNft14nXEBYMehitQ==/lib/arm64, /system/lib64]]] couldn't find "libh3-java.so"

I'm having the same problem has anybody got a solution to

[akexorcist]

armeabi, armeabi-v7a, arm64-v8a are ABIs supported in Android and this library doesn't support for x86 and x86_64

In your case, android-armv7l doesn't look like regular ABI for Android device

For regular Android device

Currently all android devices running on ARM (Except outdated device like Asus ZenPhone 5 and Chrome OS device). x86 and x86_64 are available in Android Emulator only.

So you can config your app to support ARM only in build.gradle like this

android {
    /* ... */
    defaultConfig {
        /* ... */
        ndk {
            abiFilters "armeabi", "armeabi-v7a", "arm64-v8a"
        }
    }
}

[ma-rp]

I also faced this issue, @yelsane solution worked for me, thanks.
It would be great if this library could be repackaged for Android

[mrQuidome]

I am facing the same problem. Got it working but after a Android Studio update it failed to work for me. Is it possible to fix this without the need for a workaround. Would be very nice :)

[alphanota]

@mrQuidome What are the minimum and target android API's in your project?

[mrQuidome]

Started all over again and have it working (again). That's very nice. But, the problem was something different. It works when I run it on my device It does not work when I use the emulator. Somebody an idea?

[alphanota]

@mrQuidome What architecture is your emulator using? When I had issues it was because the libh3.so didn't match the architecture of my emulator. If you're using the JNIlibs/libh3-java.so approach one thing you could do is make sure you have a libh3.so copy that is built for your emulator architecture (x86,arm,arm64, etc)

[mrQuidome]

@mrQuidome What architecture is your emulator using? When I had issues it was because the libh3.so didn't match the architecture of my emulator. If you're using the JNIlibs/libh3-java.so approach one thing you could do is make sure you have a libh3.so copy that is built for your emulator architecture (x86,arm,arm64, etc)

Thank you for your reply :)
I have put all the *.so files into their respective directories under JniLibs. Still no luck with the emulator. I am using Nexus 6, API 30 as my emulated phone.

[ben-ying]

Hi everybody,
Some update? I'm trying use H3 in android and still show this error: java.lang.UnsatisfiedLinkError: No native resource found at /android-arm64/libh3-java.so.
I'm already added android-arm64/libh3-java.so in jniLib and didn't work.

Rename your android-arm64 to just arm64.

I just managed to make the library work on my end myself. I added a StackOverflow answer here: Android h3: A Hexagonal Hierarchical Geospatial Indexing System

Here's a sample project

@yelsane did you change so files? It does work if using your so files in your demo project. But when I used so files in h3-3.7.1.jar or h3-3.4.1.jar it didn't work.
I can see you used the 3.4.1 library but your so file sha1 is different from so in h3-3.4.1.jar.

H3Core.newInstance() throws error: java.lang.UnsatisfiedLinkError: dlopen failed: library "libh3-java.so" not found.
H3Core.newSystemInstance() throws error: java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "lroundl" referenced by "/data/app/~~BreO23DLqqHC0NYue8lizA==/place.hexagon-LcpT7zLBDPKCQa0h5Qw1og==/base.apk!/lib/arm64-v8a/libh3-java.so"...

[ben-ying]

I'm using 3.6.2 and it's working.

[yelsane]

@yelsane did you change so files? It does work if using your so files in your demo project. But when I used so files in h3-3.7.1.jar or h3-3.4.1.jar it didn't work. I can see you used the 3.4.1 library but your so file sha1 is different from so in h3-3.4.1.jar.

H3Core.newInstance() throws error: java.lang.UnsatisfiedLinkError: dlopen failed: library "libh3-java.so" not found. H3Core.newSystemInstance() throws error: java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "lroundl" referenced by "/data/app/~~BreO23DLqqHC0NYue8lizA==/place.hexagon-LcpT7zLBDPKCQa0h5Qw1og==/base.apk!/lib/arm64-v8a/libh3-java.so"...

@ben-ying it's been a while since I touched this lib, but with regard to the h3 files, I didn't change anything. I just used them as is.

[bkhall]

Using library 3.7.1...

I can confirm that copying the library android jni files to the analogous android project jniLibs folders and using the newSystemInstance() call works, mostly - until we encounter a 64-bit android device. On those devices, I can further confirm that the library fails to load with aforementioned, cannot locate symbol "lroundl", error.

Update:
I also get this same error when trying to run in the emulator on a 64-bit windows machine.

[bareq]

v 3.7.2
For me worked:

arm64-v8a/libh3-java.so copied from extracted lib jar android-arm64 folder
armeabi-v7a/libh3-java.so copied from extracted lib jar android-arm folder

Initialize lib with
H3Core.newSystemInstance()

[woodii]

I am facing the same issue when using this lib (3.7.2) in my project.
Using the above workaround with copying the *.so files into the jniLibs folder does not work for the current version.

I am still get the following error:

java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "lroundl" referenced by "/data/app/~~cEniqwudw1DOL3oqPc5FzQ==/at.***.***-7KGgzWNftH-hbpzNs6zYcA==/base.apk!/lib/arm64-v8a/libh3-java.so"...

using older *.so files from e.g. @yelsane 's sample project works somehow.

[bareq]

Ok... It worked for me because I was using H3 together with Mapbox SDK. It forces using libc++_shared.so in app. This native library contains lroundl function which is missing in libh3-java.so. I can't find a way to use h3 lib without mapbox sdk for now. Does someone know how to include that C++ support to the app?

[woodii]

Something is weird about this lib in android apps. It packages *.dlls and *.dylibs but no *.so files.
Then tries to load the missing files from android- prefixed directories which is imo not common.
And furthermore its missing functions.
In my case i would have libc++_shared.so in the correct folders aswell but its not using them when it cant find it in the libh3-java.so files.

[gdogaru]

Any plans to support Android in the future? I could not get v4 nor v3 to work with the latest Android development libraries, tried all suggestions above.

[Firsto]

same here, any alternatives?

[Firsto]

That's it, I hucked the system, awesome workaround, just great.
I took .so lib for arm, stupidly renamed it to .dll and load it into H3CoreLoader as windows_x64 (otherwise I couldn't throw the path to the file, classloader gave null when opening the resource), on emulators 9 and 11 android under x86 this trick works. 😂

!!! Use only for debugging, not in prod!

---

This is original libh3-java.so file from library's \arm64\ folder, lol. 😂

[Firsto]

add to app build.gradle
debug { ndk { abiFilters "armeabi" } }

Works fine with x86 emulator API30.

[simonvar]

Hello!
Any updates on android?

[isaacbrodsky]

I've created a sample application for demonstrating how to use h3-java on Android: https://github.com/isaacbrodsky/h3-android-sample It is still a bit hacky, and requires some odd steps like manually copying the library files into the project. I'm hoping this will be helpful for those looking to use h3-java and for testing the library.