title: No implementation found for native code in android
body: <p>Now Im using ffmpeg java library in android. I want to use it directly in my app, So Im inporting this library. But I have a problem with it. </p>
  
  <pre><code>E/AndroidRuntime: FATAL EXCEPTION: main
                Process: com.softcode.kihnoplay, PID: 15313
                java.lang.UnsatisfiedLinkError: No implementation found for java.lang.String androidFfmpeg.ArmArchHelper.cpuArchFromJNI() (tried Java_androidFfmpeg_ArmArchHelper_cpuArchFromJNI and Java_androidFfmpeg_ArmArchHelper_cpuArchFromJNI__)
                    at androidFfmpeg.ArmArchHelper.cpuArchFromJNI(Native Method)
                    at androidFfmpeg.CpuArchHelper.getCpuArch(CpuArchHelper.java:16)
                    at androidFfmpeg.FFmpeg.loadBinary(FFmpeg.java:40)
                    at com.softcode.tablet.Mp3Concat_Thread.startThread(Mp3Concat_Thread.java:90)
                    at com.softcode.tablet.Mp3Concat_Thread.&lt;init&gt;(Mp3Concat_Thread.java:54)
                    at com.softcode.phone.record.view.RecordActivity.onCreate(RecordActivity.java:182)
                    at android.app.Activity.performCreate(Activity.java:6955)
                    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1126)
                    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2927)
                    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3045)
                    at android.app.ActivityThread.-wrap14(ActivityThread.java)
                    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1642)
                    at android.os.Handler.dispatchMessage(Handler.java:102)
                    at android.os.Looper.loop(Looper.java:154)
                    at android.app.ActivityThread.main(ActivityThread.java:6776)
                    at java.lang.reflect.Method.invoke(Native Method)
                    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1520)
                    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1410)
  </code></pre>
  
  <p>I don't know why this error is occurring. </p>
  
  <p>My directory tree is</p>
  
  <p><a href="https://i.stack.imgur.com/v9rys.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/v9rys.png" alt="enter image description here"></a>
  and c file code. </p>
  
  <pre><code>#include &lt;jni.h&gt;
  #include &lt;stdio.h&gt;
  #include &lt;stdlib.h&gt;
  #include &lt;cpu-features.h&gt;
  
  jstring
  Java_androidFfmpeg_ArmArchHelper_cpuArchFromJNI(JNIEnv* env, jobject       obj)
  {
  char arch_info[11] = "";
  
  if (android_getCpuFamily() == ANDROID_CPU_FAMILY_ARM) {
      strcpy(arch_info, "ARM");
  
      uint64_t cpuFeatures = android_getCpuFeatures();
      if ((cpuFeatures &amp; ANDROID_CPU_ARM_FEATURE_ARMv7) != 0) {
          strcat(arch_info, " v7");
  
          if((cpuFeatures &amp; ANDROID_CPU_ARM_FEATURE_NEON) != 0) {
              strcat(arch_info, "-neon");
          }
      }
  }
  return (*env)-&gt;NewStringUTF(env, arch_info);
  }
  </code></pre>
  
  <p>And this is a grade(app)</p>
  
  <pre><code>android {
  compileSdkVersion 27
  buildToolsVersion '27.0.3'
  defaultConfig {
      applicationId "com.softcode.kihnoplay"
      minSdkVersion 21
      targetSdkVersion 25
      versionCode 1
      versionName "1.00"
      testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
  
      renderscriptTargetApi 19
      renderscriptSupportModeEnabled true
  
      ndk {
          abiFilters "armeabi", "armeabi-v7a","x86"
      }
  
      aaptOptions
              {
                  cruncherEnabled = false
              }
  }
  
  buildTypes {
      debug {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
      }
      release {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
      }
  }
  sourceSets.main {
      jniLibs.srcDir 'src/main/libs'
      jni.srcDirs = [] //important!!!! disable automatic ndk-build call
  }
  </code></pre>
  
  <p>I don't know why this error is occurring. If you know this problem please let me know. Thanks you!</p>