java native interface - Use 32-bit jni libraries on 64-bit android

Question

I've tried running an application using a native library on the Nexus 9.

The application exits with an error message:

java.lang.UnsatisfiedLinkError: dlopen failed: "lib_xyz.so" is 32-bit instead of 64-bit

Is there any known workaround for this problem (except, of course, recompiling the library and making the apk bigger)?

Answer 1

Found an explanation: 64-bit Android can use 32-bit native libraries as a fallback, only if System.loadlLibrary() can't find anything better in the default search path. You get an UnsatisfiedLinkError if you force the system to load the 32-bit library using System.load() with the full library path. So the first workaround is using System.loadLibrary() instead of System.load().

An additional thing that has to be taken into account is that libraries cannot be mixed: the fallback behaviour only applies for the first library your application loads. If the first one is 64-bit, no 32-bit libraries can be loaded by the same application, and vice versa.