How to use a .so library during compile time only?

Issue

I have a third party .so library which I need to use at compile time only in my application. The provider of the library says:-

NOTE: DO NOT include thelibrary.so as part of agent APK. Use for compilation purpose only.

I have this in my build.gradle:-

    task ndkBuild(type: Exec, description: 'Compile JNI source via NDK') {
       def ndkDir = project.android.ndkDirectory.absolutePath
       project.logger.debug('my debug message')
       if (ndkDir == null) {
             ndkDir = "/usr/local/bin"
        }
       commandLine "$ndkDir/ndk-build",
            '-C', file('src/main').absolutePath, // Change src/main/jni the relative path to your jni source
            '-j', Runtime.runtime.availableProcessors(),
            'all',
            'NDK_DEBUG=1'
      }

    tasks.withType(JavaCompile) {
        compileTask -> compileTask.dependsOn ndkBuild
    }

and the Android.mk file looks like this:-

    LOCAL_PATH:= $(call my-dir)
    LOCAL_C_INCLUDES:= $(LOCAL_PATH)
    include $(CLEAR_VARS)
    LOCAL_C_INCLUDES:= $(LOCAL_PATH)
    LOCAL_MODULE:= mymodulename
    LOCAL_STL := c++_static
    LOCAL_CPPFLAGS := -std=c++11
    LOCAL_LDLIBS := -ldl -llog
    LOCAL_LDLIBS += -fuse-ld=bfd
    LOCAL_LDLIBS += -lz
    LOCAL_LDLIBS += -ljnigraphics
    LOCAL_LDLIBS += -landroid
    LOCAL_LDLIBS +:= -Lmylibrary.so <-------THIS IS THE THIRD PARTY LIB
    LOCAL_LDFLAGS:= -Wl,--unresolved-symbols=ignore-all
    LOCAL_SRC_FILES:= mylocalfile_using_thecode_from_so_file.cpp
    include $(BUILD_SHARED_LIBRARY)

I know I can add the myLibrary.so as a separate module and package it as a PREBUILT_SHARED_LIBRARY, but the provider of the library has said that it should not be packaged along with the apk, and should be used at compilation only.

How do I add this library for compilation only?

I am not using cmake. This is a legacy project and there is no goal to upgrade it for some reason.

---

UPDATE #1

We were using another version of this library in the project. Let us call it Version 1 and were including Version 1 as a PREBUILT_SHARED_LIBRARY. However when I use the newer Version 2 of the same library as a PREBUILT_SHARED_LIBRARY, it complains

cannot locate symbol "_ZNK7android8String164sizeEv" referenced by thefinalbuiltlibrary.so .

Regarding the ignore all symbols LDFLAG :- It is one of the many things I am just trying to make this work.

Solution

How do I add this library for compilation only?

Probably you are trying to exclude that shared library when do apk packaging. Putting below snippet into your app/build.gradle can achieve this:

android { 
    ...
    packagingOptions {
        exclude 'lib/x86/thefinalbuiltlibrary.so'
        exclude 'lib/x86_64/thefinalbuiltlibrary.so'
        exclude 'lib/armeabi-v7a/thefinalbuiltlibrary.so'
        exclude 'lib/arm64-v8a/thefinalbuiltlibrary.so'
    }
    ...
}

See: libsupportjni.so files added in the project

Answered By - shizhen