eddex :
I'm trying to use OkHttp to download a file from a webserver in an Android app. After creating a new Project with Android Studio (API level 28) I added a button and am ImageView to my Activity. The idea is to download the an image when I press the button and show it on the screen.
I'm using the latest version of OkHttp, 3.14.0.
I added <uses-permission android:name="android.permission.INTERNET"/> to the AndroidManifest.xml file.
I tried to use the OkHttpClient exactly as described in the examples. This is what my code looks like:
public class MainActivity extends AppCompatActivity {
... // onCreate method
public void btnClicked(View view) {
new DownloadImageAsyncTask().execute("https://link.to/image.jpg");
}
public class DownloadImageAsyncTask extends AsyncTask<String, Void, Bitmap> {
OkHttpClient client = new OkHttpClient();
... // override doInBackground()
}
}
When l run the app and press the button, the btnClicked() method is executed and the app crashes. The error occurs when calling OkHttpClient() no matter if I place it as a field in the DownloadImageAsyncTask class, as a local variable of the doInBackground() method or as a field in the ManActivity class.
I've also ried to use the Builder (new OkHttpClient.Builder().build()) to initialize the object but with the same outcome.
Here's the stack trace:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.myapp.httpstuff, PID: 17796
java.lang.IllegalStateException: Could not execute method for android:onClick
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:390)
at android.view.View.performClick(View.java:6597)
at android.view.View.performClickInternal(View.java:6574)
at android.view.View.access$3100(View.java:778)
at android.view.View$PerformClick.run(View.java:25885)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:385)
at android.view.View.performClick(View.java:6597)
at android.view.View.performClickInternal(View.java:6574)
at android.view.View.access$3100(View.java:778)
at android.view.View$PerformClick.run(View.java:25885)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: java.lang.BootstrapMethodError: Exception from call site #4 bootstrap method
at okhttp3.internal.Util.<clinit>(Util.java:87)
at okhttp3.internal.Util.immutableList(Util.java:234)
at okhttp3.OkHttpClient.<clinit>(OkHttpClient.java:124)
at com.myapp.httpstuff.MainActivity$DownloadImageAsyncTask.<init>(MainActivity.java:31)
at com.myapp.httpstuff.MainActivity.btnClicked(MainActivity.java:26)
at java.lang.reflect.Method.invoke(Native Method)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:385)
at android.view.View.performClick(View.java:6597)
at android.view.View.performClickInternal(View.java:6574)
at android.view.View.access$3100(View.java:778)
at android.view.View$PerformClick.run(View.java:25885)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: java.lang.ClassCastException: Bootstrap method returned null
at okhttp3.internal.Util.<clinit>(Util.java:87)
at okhttp3.internal.Util.immutableList(Util.java:234)
at okhttp3.OkHttpClient.<clinit>(OkHttpClient.java:124)
at com.myapp.httpstuff.MainActivity$DownloadImageAsyncTask.<init>(MainActivity.java:31)
at com.myapp.httpstuff.MainActivity.btnClicked(MainActivity.java:26)
at java.lang.reflect.Method.invoke(Native Method)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:385)
at android.view.View.performClick(View.java:6597)
at android.view.View.performClickInternal(View.java:6574)
at android.view.View.access$3100(View.java:778)
at android.view.View$PerformClick.run(View.java:25885)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Jesse Wilson :
OkHttp 3.13+ requires Java 8+ or Android 5+. I think you've encountered a situation where a Java 8 lambda is not expected by the ART runtime.
Handle<mirror::Object> object(hs.NewHandle(result.GetL()));
if (UNLIKELY(object.IsNull())) {
// This will typically be for LambdaMetafactory which is not supported.
ThrowClassCastException("Bootstrap method returned null");
return nullptr;
}
You'll probably have success updating your build.gradle.
android {
compileOptions {
targetCompatibility = "8"
sourceCompatibility = "8"
}
}