java.lang.UnsatisfiedLinkError: dlopen failed 64-bit instead of 32-bit while .so should be built in x86

Question

我正在尝试在 Android Studio 中使用 JNI，我在默认情况下由Android Studio创建的示例native-lib.cpp下添加了JNI函数（添加C++支持后）

但是，我遇到了一个错误

java.lang.UnsatisfiedLinkError: No implementation found for boolean com.example.user.project.Tracker.isTracking_0(boolean) (tried Java_com_example_user_project_Tracker_isTracking_10 and Java_com_example_user_project_Tracker_isTracking_10__Z)

我也试过将它添加到 MainActivity

static {
        System.loadLibrary("tracker");
   }

但我会得到另一个例外

java.lang.UnsatisfiedLinkError: dlopen failed: "/data/app/com.example.user.project/lib/x86/libtracker.so" is 64-bit instead of 32-bit

可以看到我的库已经构建成功，这是构建时显示的曲目信息

Build tracker x86 [1/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/fhog.cpp.o [2/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/tracker.cpp.o [3/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/ctracker.cpp.o [4/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/native-lib.cpp.o [5/5] Linking CXX shared library ../../../../build/intermediates/cmake/debug/obj/x86/libtracker.so Build tracker mips [1/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/tracker.cpp.o [2/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/fhog.cpp.o [3/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/ctracker.cpp.o [4/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/native-lib.cpp.o [5/5] Linking CXX shared library ../../../../build/intermediates/cmake/debug/obj/mips/libtracker.so Build tracker x86_64 [1/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/tracker.cpp.o [2/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/fhog.cpp.o [3/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/ctracker.cpp.o [4/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/native-lib.cpp.o [5/5] Linking CXX shared library ../../../../build/intermediates/cmake/debug/obj/x86_64/libtracker.so Build tracker armeabi [1/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/tracker.cpp.o [2/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/fhog.cpp.o [3/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/ctracker.cpp.o [4/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/native-lib.cpp.o [5/5] Linking CXX shared library ../../../../build/intermediates/cmake/debug/obj/armeabi/libtracker.so Build tracker armeabi-v7a [1/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/tracker.cpp.o [2/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/fhog.cpp.o [3/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/ctracker.cpp.o [4/5] Building CXX object CMakeFiles/tracker.dir/src/main/cpp/native-lib.cpp.o [5/5] Linking CXX shared library ../../../../build/intermediates/cmake/debug/obj/armeabi-v7a/libtracker.so

这是我的 CMakeLists

set (pathToOpenCv /home/user/OpenCV-android-sdk3.2)
set (pathToProject /home/user/AndroidStudioProjects/project)

cmake_minimum_required(VERSION 3.4.1)

set(CMAKE_VERBOSE_MAKEFILE on)

include_directories(${pathToOpenCv}/sdk/native/jni/include)

FILE(GLOB_RECURSE cppfiles "src/main/cpp/*.cpp")

add_library(lib_opencv SHARED IMPORTED)

add_library(tracker SHARED ${cppfiles})

set_target_properties(lib_opencv PROPERTIES IMPORTED_LOCATION ${pathToProject}/app/src/main/jniLibs/${ANDROID_ABI}/libopencv_java3.so)

find_library(
              log-lib
              log )
target_link_libraries( tracker
                       ${log-lib}
                       lib_opencv
                       )

这是我的 native-lib.cpp

#include <jni.h>
#include <string>
extern "C"
JNIEXPORT jboolean JNICALL Java_com_example_user_project_Tracker_isTracking_10
        (JNIEnv *env, jboolean boolean) {
    printf("\n c-boolean: %d ", boolean);
    if (boolean == JNI_TRUE) {
        printf("true");
    } else {
        printf("false");
    }
    boolean = false;
    return boolean;
};

那么Android工作室在我的.so库中找不到方法，出现java.lang.UnsatisfiedLinkError是什么原因呢？另外，我不明白为什么我的 x86 库是 64 位而不是 32 位。

谢谢

更新

仔细检查 android 日志，我认为它没有正确加载跟踪器库。我认为现在 64 位错误是主要问题。更新问题标题

java.lang.UnsatisfiedLinkError: dlopen failed: "/data/app/com.example.user.project/lib/x86/libtracker.so" is 64-bit instead of 32-bit

在build.gradle 我已经设置了 abiFilter，我的 AVD 是 x86 设备

应用插件：'com.android.application'

android {
    compileSdkVersion 26
    buildToolsVersion "26.0.1"
    defaultConfig {
        applicationId "com.example.user.project"
        minSdkVersion 23
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        externalNativeBuild {
            cmake {
                cppFlags ""
            }
        }
    }

    sourceSets.main {
        jniLibs.srcDir 'src/main/jniLibs'
        jni.srcDirs = []
    }



    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    externalNativeBuild {
        cmake {
            path "CMakeLists.txt"
        }
    }

    defaultConfig {
        ndk {
            abiFilters "armeabi", "armeabi-v7a", "x86", "x86_64", "mips"
        }

    }
}

// call regular ndk-build(.cmd) script from app directory


dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:26.+'
    compile 'com.android.support.constraint:constraint-layout:1.0.2'
    testCompile 'junit:junit:4.12'
    compile project(':openCVLibrary320')
}

Answer 1

这是导致您出现问题的原因：

sourceSets.main {
    jniLibs.srcDir 'src/main/jniLibs'
    jni.srcDirs = []
}

这些定义不能与 externalNativeBuild 安全共存。

基本上，在新的 Android Studio 中，jni.srcDirs 是不相关的。它通过分析您的 cmake 或 ndk-build 日志来查找要使用的 C/++ 文件。但即使您使用 externalNativeBuild，AS 也会将它在 jniLibs 中找到的二进制文件复制到最终的 APK。 libtracker.so 的错误版本不知何故卡在了 src/main/jniLibs/x86 目录中。重要的是要记住构建或重建通常不会在那里 remove/update 二进制文件。

java.lang.UnsatisfiedLinkError: dlopen failed 64-bit instead of 32-bit while .so should be built in x86

java.lang.UnsatisfiedLinkError: dlopen failed 64-bit instead of 32-bit while .so should be built in x86

c++

java

java-native-interface

android-studio