android.media package missing few classes in sdk-platforms[android.jar]

Question

I am trying to build a FM Radio kind of application and I cloned this Google Respository for the reference.

However There are few classes in the imports which are missing in android sdk. I tried changing compileSdkVersion from 18 to 24 but android.jar seems to be missing these Following imports:

import android.media.AudioManager.OnAudioFocusChangeListener;
import android.media.AudioManager.OnAudioPortUpdateListener;
import android.media.AudioMixPort;
import android.media.AudioPatch;
import android.media.AudioPort;
import android.media.AudioPortConfig;
import android.media.AudioDevicePort;
import android.media.AudioDevicePortConfig;

Where exactly are these classes and how can i import them ?

The Strange thing about them is they are present as .java files in sources/android-xx but not in actual .jar file.

The sample is showing errors and I am not able to proceed. Please guide me how to resolve this issue.

Answer 1

You can see from the Android source code that these classes are "hidden" from the jar using the "pseudo-annotation":

/* @hide */ 

For example, see here and here.

This annotation controls what will appear in the runtime Android.jar.

Note, sometimes these hidden classes are later included as part of the official SDK.

Refer to:

https://commonsware.com/blog/2018/01/18/think-hard-about-hide.html

What does @hide mean in the Android source code?

What exactly does Android's @hide annotation do?