java.lang.UnsatisfiedLinkError：无法从加载程序dalvik.system.PathClassLoader加载NativeMorphoSmartSDK_6.13.2.0-4.1

Question

I am getting null UnsatisfiedLinkError while building my app.

i am using openssl and some third party libraries to capture finger and verify them.

here is my cmake file

  # For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html

# Sets the minimum version of CMake required to build the native library.

cmake_minimum_required(VERSION 3.4.1)

# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.

add_library( # Sets the name of the library.
             native-lib

             # Sets the library as a shared library.
             SHARED

             # Provides a relative path to your source file(s).
             src/main/cpp/native-lib.cpp )


             add_library(openssl SHARED IMPORTED)
             set_target_properties (openssl PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libcrypto.so )
             set_target_properties (openssl PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libssl.so )
             set_target_properties (openssl PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libidkit.so )
             set_target_properties (openssl PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libjnidispatch.so )
             set_target_properties (openssl PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libMSO100.so )
             set_target_properties (openssl PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libNativeMorphoSmartSDK_6.13.2.0-4.1.so )




# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.

include_directories(openssl-armeabi-v7a/include/)
find_library( # Sets the name of the path variable.
              log-lib

              # Specifies the name of the NDK library that
              # you want CMake to locate.
              log )

# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.

target_link_libraries( # Specifies the target library.
                       native-lib
                      ${CMAKE_CURRENT_SOURCE_DIR}/openssl-armeabi-v7a/lib/libcrypto.a
                      ${CMAKE_CURRENT_SOURCE_DIR}/openssl-armeabi-v7a/lib/libssl.a

                       # Links the target library to the log library
                       # included in the NDK.
                       ${log-lib} )

is this correct way of loading .so file in cmake or is there any method to load .so files . help with this issue

Answer 1

Each .so file that you list is a separate library. You must give each a separate name, eg

add_library(foo SHARED IMPORTED)
set_target_properties (foo PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libcrypto.so )
add_library(prebuilt_ssl SHARED IMPORTED)
set_target_properties (prebuilt_ssl PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libssl.so )
add_library(idkit SHARED IMPORTED)
set_target_properties (idkit PROPERTIES IMPORTED_LOCATION ${PROJECT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/lib/libidkit.so )

and so on. As you can see above, the logical name is not necessarily related to the file name.

If your native-lib depends on some of them, you can use these names:

target_link_libraries( # Specifies the target library.
    native-lib foo prebuilt_ssl
    # Links the target library to the log library
    # included in the NDK.
    log )

---

Note that with NDK, you don't need find_library to add dependency on the android log library.

---

There is some self-contradiction in the CMake script that you posted. You should use OpenSSL libraries either as shared objects (as libssl.so ), or static libraries (as libssl.a ), but not both. It's OK to mix libjnidispatch.so together with libssl.a , but not libcrypto.a and libssl.so .