CameraManagerCompatApi28Impl.java
/*
* Copyright 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.camera.camera2.internal.compat;
import android.content.Context;
import android.hardware.camera2.CameraAccessException;
import android.hardware.camera2.CameraCharacteristics;
import android.hardware.camera2.CameraDevice;
import android.hardware.camera2.CameraManager;
import android.os.Build;
import androidx.annotation.GuardedBy;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RequiresApi;
import androidx.annotation.RequiresPermission;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.Executor;
@RequiresApi(28)
class CameraManagerCompatApi28Impl extends CameraManagerCompatBaseImpl {
CameraManagerCompatApi28Impl(@NonNull Context context, @Nullable Object cameraManagerParams) {
super(context, cameraManagerParams);
}
static CameraManagerCompatApi28Impl create(@NonNull Context context) {
return new CameraManagerCompatApi28Impl(context, new CameraManagerCompatParamsApi28());
}
@Override
public void registerAvailabilityCallback(@NonNull Executor executor,
@NonNull CameraManager.AvailabilityCallback callback) {
// Pass through directly to the executor API that exists on this API level.
mCameraManager.registerAvailabilityCallback(executor, callback);
}
@Override
public void unregisterAvailabilityCallback(
@NonNull CameraManager.AvailabilityCallback callback) {
// Pass through directly to override behavior defined by API 21
mCameraManager.unregisterAvailabilityCallback(callback);
}
@RequiresPermission(android.Manifest.permission.CAMERA)
@Override
public void openCamera(@NonNull String cameraId, @NonNull Executor executor,
@NonNull CameraDevice.StateCallback callback) throws CameraAccessExceptionCompat {
try {
// Pass through directly to the executor API that exists on this API level.
mCameraManager.openCamera(cameraId, executor, callback);
} catch (CameraAccessException e) {
throw CameraAccessExceptionCompat.toCameraAccessExceptionCompat(e);
} catch (IllegalArgumentException | SecurityException e) {
// Re-throw those RuntimeException will be thrown by CameraManager#openCamera.
throw e;
} catch (RuntimeException e) {
if (isDndFailCase(e)) {
throwDndException(e);
}
throw e;
}
}
@NonNull
@Override
public CameraCharacteristics getCameraCharacteristics(@NonNull String cameraId)
throws CameraAccessExceptionCompat {
CameraCharacteristics cameraCharacteristics;
try {
cameraCharacteristics = super.getCameraCharacteristics(cameraId);
if (Build.VERSION.SDK_INT == 28) {
// Update the cache if it doesn't exist.
synchronized (CameraManagerCompatParamsApi28.sCameraCharacteristicsMap) {
if (!CameraManagerCompatParamsApi28.sCameraCharacteristicsMap.containsKey(
cameraId)) {
CameraManagerCompatParamsApi28.sCameraCharacteristicsMap.put(cameraId,
cameraCharacteristics);
}
}
}
} catch (RuntimeException e) {
if (isDndFailCase(e)) {
// Get from cache if it exists.
synchronized (CameraManagerCompatParamsApi28.sCameraCharacteristicsMap) {
if (CameraManagerCompatParamsApi28.sCameraCharacteristicsMap.containsKey(
cameraId)) {
return CameraManagerCompatParamsApi28.sCameraCharacteristicsMap.get(
cameraId);
}
}
throwDndException(e);
}
throw e;
}
return cameraCharacteristics;
}
private void throwDndException(@NonNull Throwable cause) throws CameraAccessExceptionCompat {
throw new CameraAccessExceptionCompat(
CameraAccessExceptionCompat.CAMERA_UNAVAILABLE_DO_NOT_DISTURB, cause);
}
/*
* Check if the exception is due to Do Not Disturb being on, which is only on specific builds
* of P. See b/149413835 and b/132362603.
*/
private boolean isDndFailCase(@NonNull Throwable throwable) {
return Build.VERSION.SDK_INT == 28 && isDndRuntimeException(throwable);
}
/*
* The full stack
*
* java.lang.RuntimeException: Camera is being used after Camera.release() was called
* at android.hardware.Camera._enableShutterSound(Native Method)
* at android.hardware.Camera.updateAppOpsPlayAudio(Camera.java:1770)
* at android.hardware.Camera.initAppOps(Camera.java:582)
* at android.hardware.Camera.<init>(Camera.java:575)
* at android.hardware.Camera.getEmptyParameters(Camera.java:2130)
* at android.hardware.camera2.legacy.LegacyMetadataMapper.createCharacteristics
* (LegacyMetadataMapper.java:151)
* at android.hardware.camera2.CameraManager.getCameraCharacteristics(CameraManager.java:274)
*
* This method check the first stack is "_enableShutterSound"
*/
private static boolean isDndRuntimeException(@NonNull Throwable throwable) {
if (throwable.getClass().equals(RuntimeException.class)) {
StackTraceElement[] stackTraceElement;
if ((stackTraceElement = throwable.getStackTrace()) == null
|| stackTraceElement.length < 0) {
return false;
}
return "_enableShutterSound".equals(stackTraceElement[0].getMethodName());
}
return false;
}
static final class CameraManagerCompatParamsApi28 {
/*
* This is a workaround by caching CameraCharacteristics. There is an issue with the early
* version of API 28. If the device "Do Not Disturb (DND)" mode is enabled, a
* RuntimeException is thrown when calling
* CameraManager#getCameraCharacteristics() and CameraManager#openCamera(). Caching the
* CameraCharacteristics can prevent library users from encountering the exception as
* possible, even if it will rethrow CameraAccessExceptionCompat.
*
* When DND error occurs, we expect the developer can notify the user to turn off DND.
* Since developer usually do not expect API CameraManager#getCameraCharacteristics() to
* throw exception, and this API may be widely and discretely called by users, it may not be
* easy to display notification with a single design. If the exception can be thrown in a
* single location such as CameraManager#openCamera(), it is much easier to notify the
* user of the DND situation. Usually the situation that the camera fails to open is well
* handled.
*
* The cache will only be used in the case of DND failure, so it won't affect
* general use. Make the cache "static" because it is shared between CameraManagerCompat
* instances.
*/
@GuardedBy("sCameraCharacteristicsMap")
static final Map<String, CameraCharacteristics> sCameraCharacteristicsMap = new HashMap<>();
CameraManagerCompatParamsApi28() {
}
}
}