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java.lang.UnsatisfiedLinkError: dlopen failed: library "../../lib/libopencv_core.so" not found

I'm developing a face recognition application using android and openCV. My android studio version is 3.5.3 and openCV version is 3.4.10. The phone on which I'm running my application is arm64-v8a and I'm getting this error :
2020-04-15 15:00:40.425 15788-15788/com.example.opencvdemo E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.opencvdemo, PID: 15788
java.lang.UnsatisfiedLinkError: dlopen failed: "/data/app/com.example.opencvdemo-o8BNe1NoZik-avIk3otJaw==/lib/arm64/libjniopencv_contrib.so" is 32-bit instead of 64-bit
at java.lang.Runtime.loadLibrary0(Runtime.java:1071)
at java.lang.Runtime.loadLibrary0(Runtime.java:1007)
at java.lang.System.loadLibrary(System.java:1667)
at com.googlecode.javacpp.Loader.loadLibrary(Loader.java:711)
at com.googlecode.javacpp.Loader.load(Loader.java:586)
at com.googlecode.javacpp.Loader.load(Loader.java:540)
at com.googlecode.javacv.cpp.opencv_contrib.<clinit>(opencv_contrib.java:97)
at com.googlecode.javacv.cpp.opencv_contrib.createLBPHFaceRecognizer(Native Method)
at com.example.opencvdemo.CtrRecognizer.<init>(CtrRecognizer.java:40)
at com.example.opencvdemo.MainActivity$1.onManagerConnected(MainActivity.java:94)
at org.opencv.android.AsyncServiceHelper$3.onServiceConnected(AsyncServiceHelper.java:319)
at android.app.LoadedApk$ServiceDispatcher.doConnected(LoadedApk.java:1956)
at android.app.LoadedApk$ServiceDispatcher$RunConnection.run(LoadedApk.java:1988)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:224)
at android.app.ActivityThread.main(ActivityThread.java:7520)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
Caused by: java.lang.UnsatisfiedLinkError: dlopen failed: "/data/app/com.example.opencvdemo-o8BNe1NoZik-avIk3otJaw==/lib/arm64/libopencv_contrib.so" is 32-bit instead of 64-bit
at java.lang.Runtime.loadLibrary0(Runtime.java:1071)
at java.lang.Runtime.loadLibrary0(Runtime.java:1007)
at java.lang.System.loadLibrary(System.java:1667)
at com.googlecode.javacpp.Loader.loadLibrary(Loader.java:711)
at com.googlecode.javacpp.Loader.load(Loader.java:577)
at com.googlecode.javacpp.Loader.load(Loader.java:540) 
at com.googlecode.javacv.cpp.opencv_contrib.<clinit>(opencv_contrib.java:97) 
at com.googlecode.javacv.cpp.opencv_contrib.createLBPHFaceRecognizer(Native Method) 
at com.example.opencvdemo.CtrRecognizer.<init>(CtrRecognizer.java:40) 
at com.example.opencvdemo.MainActivity$1.onManagerConnected(MainActivity.java:94) 
at org.opencv.android.AsyncServiceHelper$3.onServiceConnected(AsyncServiceHelper.java:319) 
at android.app.LoadedApk$ServiceDispatcher.doConnected(LoadedApk.java:1956) 
at android.app.LoadedApk$ServiceDispatcher$RunConnection.run(LoadedApk.java:1988) 
at android.os.Handler.handleCallback(Handler.java:883) 
at android.os.Handler.dispatchMessage(Handler.java:100) 
at android.os.Looper.loop(Looper.java:224) 
at android.app.ActivityThread.main(ActivityThread.java:7520) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950) 
2020-04-15 15:00:40.427 15788-15788/com.example.opencvdemo E/MQSEventManagerDelegate: failed to get MQSService.
build.gradle
apply plugin: 'com.android.application'
android {
compileSdkVersion 28
//buildToolsVersion "29.0.0"
defaultConfig {
applicationId "com.example.opencvdemo"
minSdkVersion 19
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
sourceSets {
main {
jni.srcDirs = ['src/main/jniLibs']
jniLibs.srcDir 'src/main/libs'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar','*.so'])
implementation 'androidx.legacy:legacy-support-v4:1.0.0'
implementation 'com.intuit.sdp:sdp-android:1.0.6'
implementation 'com.intuit.ssp:ssp-android:1.0.6'
implementation 'com.google.android.material:material:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
implementation 'com.github.bumptech.glide:glide:3.7.0'
implementation 'com.github.markushi:circlebutton:1.1'
implementation project(path: ':openCV3410')
}
For removing this error I made changes to my build.gradle as follows:
apply plugin: 'com.android.application'
android {
compileSdkVersion 28
//buildToolsVersion "29.0.0"
defaultConfig {
applicationId "com.example.opencvdemo"
minSdkVersion 19
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
ndk {
abiFilters "armeabi-v7a", "x86", "armeabi", "mips"
}
externalNativeBuild {
cmake {
cppFlags "-frtti -fexceptions"
}
}
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
sourceSets {
main {
jni.srcDirs = ['src/main/jniLibs']
jniLibs.srcDir 'src/main/libs'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar','*.so'])
implementation 'androidx.legacy:legacy-support-v4:1.0.0'
implementation 'com.intuit.sdp:sdp-android:1.0.6'
implementation 'com.intuit.ssp:ssp-android:1.0.6'
implementation 'com.google.android.material:material:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
implementation 'com.github.bumptech.glide:glide:3.7.0'
implementation 'com.github.markushi:circlebutton:1.1'
implementation project(path: ':openCV3410')
}
Now I'm getting this error :
2020-04-15 15:11:19.353 17892-17892/com.example.opencvdemo E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.opencvdemo, PID: 17892
java.lang.UnsatisfiedLinkError: dlopen failed: library "../../lib/libopencv_core.so" not found
at java.lang.Runtime.loadLibrary0(Runtime.java:1071)
at java.lang.Runtime.loadLibrary0(Runtime.java:1007)
at java.lang.System.loadLibrary(System.java:1667)
at com.googlecode.javacpp.Loader.loadLibrary(Loader.java:711)
at com.googlecode.javacpp.Loader.load(Loader.java:586)
at com.googlecode.javacpp.Loader.load(Loader.java:540)
at com.googlecode.javacv.cpp.opencv_contrib.<clinit>(opencv_contrib.java:97)
at com.googlecode.javacv.cpp.opencv_contrib.createLBPHFaceRecognizer(Native Method)
at com.example.opencvdemo.CtrRecognizer.<init>(CtrRecognizer.java:40)
at com.example.opencvdemo.MainActivity$1.onManagerConnected(MainActivity.java:94)
at com.example.opencvdemo.MainActivity.onResume(MainActivity.java:233)
at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1454)
at android.app.Activity.performResume(Activity.java:8050)
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4236)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:4278)
at android.app.servertransaction.ResumeActivityItem.execute(ResumeActivityItem.java:52)
at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:176)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2040)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:224)
at android.app.ActivityThread.main(ActivityThread.java:7520)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
Caused by: java.lang.UnsatisfiedLinkError: dlopen failed: library "../../lib/libopencv_core.so" not found
at java.lang.Runtime.loadLibrary0(Runtime.java:1071)
at java.lang.Runtime.loadLibrary0(Runtime.java:1007)
at java.lang.System.loadLibrary(System.java:1667)
at com.googlecode.javacpp.Loader.loadLibrary(Loader.java:711)
at com.googlecode.javacpp.Loader.load(Loader.java:577)
at com.googlecode.javacpp.Loader.load(Loader.java:540) 
at com.googlecode.javacv.cpp.opencv_contrib.<clinit>(opencv_contrib.java:97) 
at com.googlecode.javacv.cpp.opencv_contrib.createLBPHFaceRecognizer(Native Method) 
at com.example.opencvdemo.CtrRecognizer.<init>(CtrRecognizer.java:40) 
at com.example.opencvdemo.MainActivity$1.onManagerConnected(MainActivity.java:94) 
at com.example.opencvdemo.MainActivity.onResume(MainActivity.java:233) 
at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1454) 
at android.app.Activity.performResume(Activity.java:8050) 
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4236) 
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:4278) 
at android.app.servertransaction.ResumeActivityItem.execute(ResumeActivityItem.java:52) 
at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:176) 
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2040) 
at android.os.Handler.dispatchMessage(Handler.java:107) 
at android.os.Looper.loop(Looper.java:224) 
at android.app.ActivityThread.main(ActivityThread.java:7520) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950) 
2020-04-15 15:11:19.361 17892-17892/com.example.opencvdemo E/MQSEventManagerDelegate: failed to get MQSService.

According to the stack trace: java.lang.UnsatisfiedLinkError: dlopen failed: "/data/app/com.example.opencvdemo-o8BNe1NoZik-avIk3otJaw==/lib/arm64/libjniopencv_contrib.so" is 32-bit instead of 64-bit
So I suppose that your library doesn't have resources for arm64-v8a, to solve this problem you must add to your project opencv .so files for arm64-v8a arch

Follow these steps if you are getting .so file not found in jniLibs folder
1- add source path in android in buildgradle file below defaultConfig
sourceSets {
main {
jniLibs.srcDirs = ['src/main/jniLibs']
}
}
2- add ndk in defaultConfig in buildgradle file. abifilters can be found in jniLibs folders containing missing files.
ndk{
abiFilters 'armeabi-v7a'
}
if not resolved then visit this link https://blog.csdn.net/u010920692/article/details/114476490

Kotlin Class.forName fails for Mysql connector/j driver with NoSuchMethodError

I've added the my Connector/j 8.0 mysql-connector-java-8.0.16.jar file to my libs folder and added an entry in my app module build.gradle file.
But I get a java.lang.NoSuchMethodError exception when i try to Class.forName("com.mysql.cj.jdbc.Driver").newInstance() which is below:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.testmate.hscmate, PID: 10196
java.lang.NoSuchMethodError: No static method metafactory(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite; in class Ljava/lang/invoke/LambdaMetafactory; or its super classes (declaration of 'java.lang.invoke.LambdaMetafactory' appears in /apex/com.android.runtime/javalib/core-oj.jar)
at com.mysql.cj.jdbc.AbandonedConnectionCleanupThread.<clinit>(AbandonedConnectionCleanupThread.java:58)
at java.lang.Class.classForName(Native Method)
at java.lang.Class.forName(Class.java:454)
at java.lang.Class.forName(Class.java:379)
at com.mysql.cj.jdbc.NonRegisteringDriver.<clinit>(NonRegisteringDriver.java:99)
at java.lang.Class.classForName(Native Method)
at java.lang.Class.forName(Class.java:454)
at java.lang.Class.forName(Class.java:379)
at com.testmate.hscmate.MainActivity$onNavigationItemSelectedListener$1.onNavigationItemSelected(MainActivity.kt:24)
at com.google.android.material.bottomnavigation.BottomNavigationView$1.onMenuItemSelected(BottomNavigationView.java:204)
at androidx.appcompat.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:840)
at androidx.appcompat.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:991)
at com.google.android.material.bottomnavigation.BottomNavigationMenuView$1.onClick(BottomNavigationMenuView.java:115)
at android.view.View.performClick(View.java:7125)
at android.view.View.performClickInternal(View.java:7102)
at android.view.View.access$3400(View.java:801)
at android.view.View$PerformClick.run(View.java:27301)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7319)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:934)
here is my build.gradle:
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
android {
compileSdkVersion 29
buildToolsVersion "29.0.0"
defaultConfig {
applicationId "com.testmate.hscmate"
minSdkVersion 26
targetSdkVersion 29
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
implementation 'androidx.appcompat:appcompat:1.0.2'
implementation 'androidx.core:core-ktx:1.0.2'
implementation 'com.google.android.material:material:1.0.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test:runner:1.2.0'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
implementation files('libs/mysql-connector-java-8.0.16.jar')
}
As far as I can tell, kotlin is finding the .jar, because otherwise it would be a ClassNotFoundException but it seems my SDK or JRE is missing this "static method metafactory" or something.
Connector/j 8.0 requires java 1.8.x which I believe I'm running with my compileSdkVersion and targetSdkVersion. I tried downloading sdkVersion 27 to build the app in a lower version but the app doesn't build.
I have no idea why my driver can't seem to find the things it needs.

Getting no class def error when using a specific library

I am getting a NoClassDefFoundError only when I use a specific library along with the adobe aviary library.
Gradle and error are shown below Code seem to be working when I don't use that crop library. I really want to use that library as all of my code is configured according to it. Please give me a solution for this
apply plugin: 'com.android.application'
android {
compileSdkVersion 26
buildToolsVersion "26.0.0"
defaultConfig {
applicationId "com.jetslice.retroart1"
manifestPlaceholders = [appPackageName: "com.jetslice.retroart1"]
minSdkVersion 19
targetSdkVersion 26
renderscriptTargetApi 21
renderscriptSupportModeEnabled true
versionCode 1
versionName "1.0"
multiDexEnabled true
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
configurations.all {
resolutionStrategy.force 'com.google.code.findbugs:jsr305:1.3.9'
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
dexOptions {
jumboMode true
}
dexOptions {
javaMaxHeapSize "64k"
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:design:26.0.0-alpha1'
compile 'com.android.support:design:26.0.0-alpha1'
compile 'com.android.support.constraint:constraint-layout:1.0.2'
compile 'com.github.clans:fab:1.6.4'
compile 'com.adobe.creativesdk.foundation:auth:0.9.1251'
compile 'com.adobe.creativesdk:image:4.8.4'
compile 'com.localytics.android:library:3.8.0'
compile 'com.adobe.creativesdk.foundation:assetux:0.9.1251'
compile 'com.adobe.creativesdk.foundation:assetcore:0.9.1251'
compile 'com.android.support:multidex:1.0.1'
compile 'com.ms.square:glassview:0.1.0'
compile 'com.android.support:support-v4:26.+'
compile 'com.jpeng:jpspringmenu:1.0.1'
compile 'com.github.mzelzoghbi:zgallery:0.3'
compile 'com.github.doctoror.particlesdrawable:library:1.0.8'
compile 'com.theartofdev.edmodo:android-image-cropper:2.6.+'
compile 'hanks.xyz:htextview-library:0.1.5'
compile 'com.github.MorochoRochaDarwin:HorizontalScrollMenu:2.0.0'
compile 'com.theartofdev.edmodo:android-image-cropper:2.6.+'
testCompile 'junit:junit:4.12'
}
Error:
02-19 18:55:48.042 25223-25223/com.jetslice.retroart1 E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.jetslice.retroart1, PID: 25223
java.lang.NoClassDefFoundError: Failed resolution of: Landroid/support/v4/os/AsyncTaskCompat;
at com.adobe.creativesdk.aviary.AdobeImageEditorActivityAbstract.loadTools(AdobeImageEditorActivityAbstract.java:760)
at com.adobe.creativesdk.aviary.AdobeImageEditorActivityAbstract.onPostCreate(AdobeImageEditorActivityAbstract.java:579)
at android.app.Instrumentation.callActivityOnPostCreate(Instrumentation.java:1195)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2542)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2626)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:207)
at android.app.ActivityThread.main(ActivityThread.java:5740)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:905)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:766)
Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.v4.os.AsyncTaskCompat" on path: DexPathList[[zip file "/data/app/com.jetslice.retroart1-1/base.apk"],nativeLibraryDirectories=[/data/app/com.jetslice.retroart1-1/lib/arm, /data/app/com.jetslice.retroart1-1/base.apk!/lib/armeabi-v7a, /vendor/lib, /system/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
at com.adobe.creativesdk.aviary.AdobeImageEditorActivityAbstract.loadTools(AdobeImageEditorActivityAbstract.java:760)
at com.adobe.creativesdk.aviary.AdobeImageEditorActivityAbstract.onPostCreate(AdobeImageEditorActivityAbstract.java:579)
at android.app.Instrumentation.callActivityOnPostCreate(Instrumentation.java:1195)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2542)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2626)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:207)
at android.app.ActivityThread.main(ActivityThread.java:5740)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:905)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:766)
Suppressed: java.lang.ClassNotFoundException: android.support.v4.os.AsyncTaskCompat
at java.lang.Class.classForName(Native Method)
at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
... 14 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack trace available

Realm android, RealmTransformer doesn't seem to be applied

i'm newbie.
I use:
Android studio 2.2.3
Gradle: 2.14.1
Realm-plugin: "classpath "io.realm:realm-gradle-plugin:2.2.1""
But it throws an exception while I'm calling Realm.init(context); in the onCreate of my Activity.
Log:
12-14 16:40:51.096 3541-3541/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: *.demo, PID: 3541
java.lang.ExceptionInInitializerError: RealmTransformer doesn't seem to be applied. Please update the project configuration to use the Realm Gradle plugin. See https://realm.io/news/android-installation-change/
at io.realm.RealmConfiguration.<clinit>(RealmConfiguration.java:77)
at io.realm.RealmConfiguration$Builder.initializeBuilder(RealmConfiguration.java:414)
at io.realm.RealmConfiguration$Builder.<init>(RealmConfiguration.java:402)
at io.realm.Realm.init(Realm.java:188)
at *.demo.MainActivity.onCreate(MainActivity.java:21)
at android.app.Activity.performCreate(Activity.java:6237)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
My Class:
import io.realm.Realm;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Realm.init(this); //crashing line
}
}
Build.gradle module level:
apply plugin: 'com.android.application'
apply plugin: 'realm-android'
android {
compileSdkVersion 25
buildToolsVersion "25.0.2"
defaultConfig {
applicationId "*.demo"
minSdkVersion 10
targetSdkVersion 25
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
jackOptions {
enabled true
}
// Enabling multidex support.
multiDexEnabled true
}
buildTypes {
release {
minifyEnabled false
//proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
compileOptions {
targetCompatibility 1.8
sourceCompatibility 1.8
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:25.1.0'
compile 'com.android.support:design:25.1.0'
compile 'com.android.support:multidex:1.0.1'
compile 'com.github.pwittchen:reactivenetwork:0.7.0'
testCompile 'junit:junit:4.12'
}
thanks in advance for help.

Jack doesn't work with the Transform API in Gradle.
As a result, the Realm-Transformer, which relies on the Transform API, cannot be used with Jack.
Use Retrolambda instead of Jack for Java 8 feature support.

You need to add this to the your d build.gradle file. :
repositories {
jcenter()
}
dependencies {
classpath "io.realm:realm-gradle-plugin:2.2.1"
}
Then do:
Once these two changes are made, simply refresh your gradle dependencies. If you are upgrading from a version prior to v0.88 you may also need to clean your gradle project (./gradlew clean) to remove any lingering previous installations.
Instructions can be found here, on the Realm website.

Unxepcted ClassCastException from findViewById

I have the following code in xml file:
<android.support.v7.widget.GridLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id = "#+id/buttonsLayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity = "center"
app:columnCount="4"
app:rowCount="4"
app:useDefaultMargins="false"
>
</android.support.v7.widget.GridLayout>
and I'm filling this GridLayout dynamicly so I'm trying to get the object with:
android.support.v7.widget.GridLayout gl =
(android.support.v7.widget.GridLayout)findViewById(R.id.buttonsLayout);
Which gives me the following error:
Caused by: java.lang.ClassCastException: android.support.v7.internal.widget.TintButton cannot be cast to android.support.v7.widget.GridLayout at com.education4all.mathcoach.TaskActivity.onCreate(TaskActivity.java:134)
at android.app.Activity.performCreate(Activity.java:4465)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2033)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2104) 
at android.app.ActivityThread.access$600(ActivityThread.java:132) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1157) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:137) 
at android.app.ActivityThread.main(ActivityThread.java:4575) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:511) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:556) 
at dalvik.system.NativeStart.main(Native Method)
This is very strange because this code used to work and suddenly this error appears. Why could that be?
build_gradle:
apply plugin: 'com.android.application'
android {
compileSdkVersion 22
buildToolsVersion '21.1.2'
defaultConfig {
applicationId "com.education4all.mathcoach"
minSdkVersion 10
targetSdkVersion 22
versionName '1.0.2'
versionCode 4
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
productFlavors {
}
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:appcompat-v7:22.0.0'
compile 'com.android.support:gridlayout-v7:18.0.+'
}

Try to use a higher version of the support library, i.e.: com.android.support:appcompat-v7:22.+, clean and try to run the project.
You can also use the latest version of the GridLayout as well.