updater_sample/src/com/example/android/systemupdatersample/UpdateManager.java - platform/bootable/recovery - Git at Google

 /*
  * Copyright (C) 2018 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 com.example.android.systemupdatersample;

 import android.content.Context;
 import android.os.UpdateEngine;
 import android.os.UpdateEngineCallback;
 import android.util.Log;

 import com.example.android.systemupdatersample.services.PrepareStreamingService;
 import com.example.android.systemupdatersample.util.PayloadSpecs;
 import com.example.android.systemupdatersample.util.UpdateEngineErrorCodes;
 import com.example.android.systemupdatersample.util.UpdateEngineProperties;
 import com.example.android.systemupdatersample.util.UpdaterStates;
 import com.google.common.util.concurrent.AtomicDouble;

 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.DoubleConsumer;
 import java.util.function.IntConsumer;

 /**
  * Manages the update flow. It has its own state (in memory), separate from
  * {@link UpdateEngine}'s state. Asynchronously interacts with the {@link UpdateEngine}.
  */
 public class UpdateManager {

     private static final String TAG = "UpdateManager";

     /** HTTP Header: User-Agent; it will be sent to the server when streaming the payload. */
     private static final String HTTP_USER_AGENT = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
             + "AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36";

     private final UpdateEngine mUpdateEngine;
     private final PayloadSpecs mPayloadSpecs;

     private AtomicInteger mUpdateEngineStatus =
             new AtomicInteger(UpdateEngine.UpdateStatusConstants.IDLE);
     private AtomicInteger mEngineErrorCode = new AtomicInteger(UpdateEngineErrorCodes.UNKNOWN);
     private AtomicDouble mProgress = new AtomicDouble(0);

     private AtomicInteger mState = new AtomicInteger(UpdaterStates.IDLE);

     private final UpdateManager.UpdateEngineCallbackImpl
             mUpdateEngineCallback = new UpdateManager.UpdateEngineCallbackImpl();

     private PayloadSpec mLastPayloadSpec;
     private AtomicBoolean mManualSwitchSlotRequired = new AtomicBoolean(true);

     private IntConsumer mOnStateChangeCallback = null;
     private IntConsumer mOnEngineStatusUpdateCallback = null;
     private DoubleConsumer mOnProgressUpdateCallback = null;
     private IntConsumer mOnEngineCompleteCallback = null;

     private final Object mLock = new Object();

     public UpdateManager(UpdateEngine updateEngine, PayloadSpecs payloadSpecs) {
         this.mUpdateEngine = updateEngine;
         this.mPayloadSpecs = payloadSpecs;
     }

     /**
      * Binds to {@link UpdateEngine}.
      */
     public void bind() {
         this.mUpdateEngine.bind(mUpdateEngineCallback);
     }

     /**
      * Unbinds from {@link UpdateEngine}.
      */
     public void unbind() {
         this.mUpdateEngine.unbind();
     }

     /**
      * @return a number from {@code 0.0} to {@code 1.0}.
      */
     public float getProgress() {
         return (float) this.mProgress.get();
     }

     /**
      * Returns true if manual switching slot is required. Value depends on
      * the update config {@code ab_config.force_switch_slot}.
      */
     public boolean isManualSwitchSlotRequired() {
         return mManualSwitchSlotRequired.get();
     }

     /**
      * Sets SystemUpdaterSample app state change callback. Value of {@code state} will be one
      * of the values from {@link UpdaterStates}.
      *
      * @param onStateChangeCallback a callback with parameter {@code state}.
      */
     public void setOnStateChangeCallback(IntConsumer onStateChangeCallback) {
         synchronized (mLock) {
             this.mOnStateChangeCallback = onStateChangeCallback;
         }
     }

     private Optional<IntConsumer> getOnStateChangeCallback() {
         synchronized (mLock) {
             return mOnStateChangeCallback == null
                     ? Optional.empty()
                     : Optional.of(mOnStateChangeCallback);
         }
     }

     /**
      * Sets update engine status update callback. Value of {@code status} will
      * be one of the values from {@link UpdateEngine.UpdateStatusConstants}.
      *
      * @param onStatusUpdateCallback a callback with parameter {@code status}.
      */
     public void setOnEngineStatusUpdateCallback(IntConsumer onStatusUpdateCallback) {
         synchronized (mLock) {
             this.mOnEngineStatusUpdateCallback = onStatusUpdateCallback;
         }
     }

     private Optional<IntConsumer> getOnEngineStatusUpdateCallback() {
         synchronized (mLock) {
             return mOnEngineStatusUpdateCallback == null
                     ? Optional.empty()
                     : Optional.of(mOnEngineStatusUpdateCallback);
         }
     }

     /**
      * Sets update engine payload application complete callback. Value of {@code errorCode} will
      * be one of the values from {@link UpdateEngine.ErrorCodeConstants}.
      *
      * @param onComplete a callback with parameter {@code errorCode}.
      */
     public void setOnEngineCompleteCallback(IntConsumer onComplete) {
         synchronized (mLock) {
             this.mOnEngineCompleteCallback = onComplete;
         }
     }

     private Optional<IntConsumer> getOnEngineCompleteCallback() {
         synchronized (mLock) {
             return mOnEngineCompleteCallback == null
                     ? Optional.empty()
                     : Optional.of(mOnEngineCompleteCallback);
         }
     }

     /**
      * Sets progress update callback. Progress is a number from {@code 0.0} to {@code 1.0}.
      *
      * @param onProgressCallback a callback with parameter {@code progress}.
      */
     public void setOnProgressUpdateCallback(DoubleConsumer onProgressCallback) {
         synchronized (mLock) {
             this.mOnProgressUpdateCallback = onProgressCallback;
         }
     }

     private Optional<DoubleConsumer> getOnProgressUpdateCallback() {
         synchronized (mLock) {
             return mOnProgressUpdateCallback == null
                     ? Optional.empty()
                     : Optional.of(mOnProgressUpdateCallback);
         }
     }

     /**
      * Updates {@link this.mState} and if state is changed,
      * it also notifies {@link this.mOnStateChangeCallback}.
      */
     private void setUpdaterState(int updaterState) {
         int previousState = mState.get();
         mState.set(updaterState);
         if (previousState != updaterState) {
             getOnStateChangeCallback().ifPresent(callback -> callback.accept(updaterState));
         }
     }

     /**
      * Requests update engine to stop any ongoing update. If an update has been applied,
      * leave it as is.
      *
      * <p>Sometimes it's possible that the
      * update engine would throw an error when the method is called, and the only way to
      * handle it is to catch the exception.</p>
      */
     public void cancelRunningUpdate() {
         try {
             mUpdateEngine.cancel();
             setUpdaterState(UpdaterStates.IDLE);
         } catch (Exception e) {
             Log.w(TAG, "UpdateEngine failed to stop the ongoing update", e);
         }
     }

     /**
      * Resets update engine to IDLE state. If an update has been applied it reverts it.
      *
      * <p>Sometimes it's possible that the
      * update engine would throw an error when the method is called, and the only way to
      * handle it is to catch the exception.</p>
      */
     public void resetUpdate() {
         try {
             mUpdateEngine.resetStatus();
             setUpdaterState(UpdaterStates.IDLE);
         } catch (Exception e) {
             Log.w(TAG, "UpdateEngine failed to reset the update", e);
         }
     }

     /**
      * Applies the given update.
      *
      * <p>UpdateEngine works asynchronously. This method doesn't wait until
      * end of the update.</p>
      */
     public void applyUpdate(Context context, UpdateConfig config) {
         mEngineErrorCode.set(UpdateEngineErrorCodes.UNKNOWN);
         setUpdaterState(UpdaterStates.RUNNING);

         if (!config.getAbConfig().getForceSwitchSlot()) {
             mManualSwitchSlotRequired.set(true);
         } else {
             mManualSwitchSlotRequired.set(false);
         }

         if (config.getInstallType() == UpdateConfig.AB_INSTALL_TYPE_NON_STREAMING) {
             applyAbNonStreamingUpdate(config);
         } else {
             applyAbStreamingUpdate(context, config);
         }
     }

     private void applyAbNonStreamingUpdate(UpdateConfig config) {
         List<String> extraProperties = prepareExtraProperties(config);

         PayloadSpec payload;
         try {
             payload = mPayloadSpecs.forNonStreaming(config.getUpdatePackageFile());
         } catch (IOException e) {
             Log.e(TAG, "Error creating payload spec", e);
             setUpdaterState(UpdaterStates.ERROR);
             return;
         }
         updateEngineApplyPayload(payload, extraProperties);
     }

     private void applyAbStreamingUpdate(Context context, UpdateConfig config) {
         List<String> extraProperties = prepareExtraProperties(config);

         Log.d(TAG, "Starting PrepareStreamingService");
         PrepareStreamingService.startService(context, config, (code, payloadSpec) -> {
             if (code == PrepareStreamingService.RESULT_CODE_SUCCESS) {
                 extraProperties.add("USER_AGENT=" + HTTP_USER_AGENT);
                 config.getStreamingMetadata()
                         .getAuthorization()
                         .ifPresent(s -> extraProperties.add("AUTHORIZATION=" + s));
                 updateEngineApplyPayload(payloadSpec, extraProperties);
             } else {
                 Log.e(TAG, "PrepareStreamingService failed, result code is " + code);
                 setUpdaterState(UpdaterStates.ERROR);
             }
         });
     }

     private List<String> prepareExtraProperties(UpdateConfig config) {
         List<String> extraProperties = new ArrayList<>();

         if (!config.getAbConfig().getForceSwitchSlot()) {
             // Disable switch slot on reboot, which is enabled by default.
             // User will enable it manually by clicking "Switch Slot" button on the screen.
             extraProperties.add(UpdateEngineProperties.PROPERTY_DISABLE_SWITCH_SLOT_ON_REBOOT);
         }
         return extraProperties;
     }

     /**
      * Applies given payload.
      *
      * <p>UpdateEngine works asynchronously. This method doesn't wait until
      * end of the update.</p>
      *
      * <p>It's possible that the update engine throws a generic error, such as upon seeing invalid
      * payload properties (which come from OTA packages), or failing to set up the network
      * with the given id.</p>
      *
      * @param payloadSpec contains url, offset and size to {@code PAYLOAD_BINARY_FILE_NAME}
      * @param extraProperties additional properties to pass to {@link UpdateEngine#applyPayload}
      */
     private void updateEngineApplyPayload(PayloadSpec payloadSpec, List<String> extraProperties) {
         mLastPayloadSpec = payloadSpec;

         ArrayList<String> properties = new ArrayList<>(payloadSpec.getProperties());
         if (extraProperties != null) {
             properties.addAll(extraProperties);
         }
         try {
             mUpdateEngine.applyPayload(
                     payloadSpec.getUrl(),
                     payloadSpec.getOffset(),
                     payloadSpec.getSize(),
                     properties.toArray(new String[0]));
         } catch (Exception e) {
             Log.e(TAG, "UpdateEngine failed to apply the update", e);
             setUpdaterState(UpdaterStates.ERROR);
         }
     }

     /**
      * Sets the new slot that has the updated partitions as the active slot,
      * which device will boot into next time.
      * This method is only supposed to be called after the payload is applied.
      *
      * Invoking {@link UpdateEngine#applyPayload} with the same payload url, offset, size
      * and payload metadata headers doesn't trigger new update. It can be used to just switch
      * active A/B slot.
      *
      * {@link UpdateEngine#applyPayload} might take several seconds to finish, and it will
      * invoke callbacks {@link this#onStatusUpdate} and {@link this#onPayloadApplicationComplete)}.
      */
     public void setSwitchSlotOnReboot() {
         Log.d(TAG, "setSwitchSlotOnReboot invoked");
         List<String> extraProperties = new ArrayList<>();
         // PROPERTY_SKIP_POST_INSTALL should be passed on to skip post-installation hooks.
         extraProperties.add(UpdateEngineProperties.PROPERTY_SKIP_POST_INSTALL);
         // It sets property SWITCH_SLOT_ON_REBOOT=1 by default.
         // HTTP headers are not required, UpdateEngine is not expected to stream payload.
         updateEngineApplyPayload(mLastPayloadSpec, extraProperties);
     }

     private void onStatusUpdate(int status, float progress) {
         int previousStatus = mUpdateEngineStatus.get();
         mUpdateEngineStatus.set(status);
         mProgress.set(progress);

         getOnProgressUpdateCallback().ifPresent(callback -> callback.accept(progress));

         if (previousStatus != status) {
             getOnEngineStatusUpdateCallback().ifPresent(callback -> callback.accept(status));
         }
     }

     private void onPayloadApplicationComplete(int errorCode) {
         Log.d(TAG, "onPayloadApplicationComplete invoked, errorCode=" + errorCode);
         mEngineErrorCode.set(errorCode);
         if (errorCode == UpdateEngine.ErrorCodeConstants.SUCCESS
                 || errorCode == UpdateEngineErrorCodes.UPDATED_BUT_NOT_ACTIVE) {
             setUpdaterState(UpdaterStates.FINISHED);
         } else if (errorCode != UpdateEngineErrorCodes.USER_CANCELLED) {
             setUpdaterState(UpdaterStates.ERROR);
         }

         getOnEngineCompleteCallback()
                 .ifPresent(callback -> callback.accept(errorCode));
     }

     /**
      * Helper class to delegate {@code update_engine} callbacks to UpdateManager
      */
     class UpdateEngineCallbackImpl extends UpdateEngineCallback {
         @Override
         public void onStatusUpdate(int status, float percent) {
             UpdateManager.this.onStatusUpdate(status, percent);
         }

         @Override
         public void onPayloadApplicationComplete(int errorCode) {
             UpdateManager.this.onPayloadApplicationComplete(errorCode);
         }
     }

 }
	/*
	* Copyright (C) 2018 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 com.example.android.systemupdatersample;

	import android.content.Context;
	import android.os.UpdateEngine;
	import android.os.UpdateEngineCallback;
	import android.util.Log;

	import com.example.android.systemupdatersample.services.PrepareStreamingService;
	import com.example.android.systemupdatersample.util.PayloadSpecs;
	import com.example.android.systemupdatersample.util.UpdateEngineErrorCodes;
	import com.example.android.systemupdatersample.util.UpdateEngineProperties;
	import com.example.android.systemupdatersample.util.UpdaterStates;
	import com.google.common.util.concurrent.AtomicDouble;

	import java.io.IOException;
	import java.util.ArrayList;
	import java.util.List;
	import java.util.Optional;
	import java.util.concurrent.atomic.AtomicBoolean;
	import java.util.concurrent.atomic.AtomicInteger;
	import java.util.function.DoubleConsumer;
	import java.util.function.IntConsumer;

	/**
	* Manages the update flow. It has its own state (in memory), separate from
	* {@link UpdateEngine}'s state. Asynchronously interacts with the {@link UpdateEngine}.
	*/
	public class UpdateManager {

	private static final String TAG = "UpdateManager";

	/** HTTP Header: User-Agent; it will be sent to the server when streaming the payload. */
	private static final String HTTP_USER_AGENT = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
	+ "AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36";

	private final UpdateEngine mUpdateEngine;
	private final PayloadSpecs mPayloadSpecs;

	private AtomicInteger mUpdateEngineStatus =
	new AtomicInteger(UpdateEngine.UpdateStatusConstants.IDLE);
	private AtomicInteger mEngineErrorCode = new AtomicInteger(UpdateEngineErrorCodes.UNKNOWN);
	private AtomicDouble mProgress = new AtomicDouble(0);

	private AtomicInteger mState = new AtomicInteger(UpdaterStates.IDLE);

	private final UpdateManager.UpdateEngineCallbackImpl
	mUpdateEngineCallback = new UpdateManager.UpdateEngineCallbackImpl();

	private PayloadSpec mLastPayloadSpec;
	private AtomicBoolean mManualSwitchSlotRequired = new AtomicBoolean(true);

	private IntConsumer mOnStateChangeCallback = null;
	private IntConsumer mOnEngineStatusUpdateCallback = null;
	private DoubleConsumer mOnProgressUpdateCallback = null;
	private IntConsumer mOnEngineCompleteCallback = null;

	private final Object mLock = new Object();

	public UpdateManager(UpdateEngine updateEngine, PayloadSpecs payloadSpecs) {
	this.mUpdateEngine = updateEngine;
	this.mPayloadSpecs = payloadSpecs;
	}

	/**
	* Binds to {@link UpdateEngine}.
	*/
	public void bind() {
	this.mUpdateEngine.bind(mUpdateEngineCallback);
	}

	/**
	* Unbinds from {@link UpdateEngine}.
	*/
	public void unbind() {
	this.mUpdateEngine.unbind();
	}

	/**
	* @return a number from {@code 0.0} to {@code 1.0}.
	*/
	public float getProgress() {
	return (float) this.mProgress.get();
	}

	/**
	* Returns true if manual switching slot is required. Value depends on
	* the update config {@code ab_config.force_switch_slot}.
	*/
	public boolean isManualSwitchSlotRequired() {
	return mManualSwitchSlotRequired.get();
	}

	/**
	* Sets SystemUpdaterSample app state change callback. Value of {@code state} will be one
	* of the values from {@link UpdaterStates}.
	*
	* @param onStateChangeCallback a callback with parameter {@code state}.
	*/
	public void setOnStateChangeCallback(IntConsumer onStateChangeCallback) {
	synchronized (mLock) {
	this.mOnStateChangeCallback = onStateChangeCallback;
	}
	}

	private Optional<IntConsumer> getOnStateChangeCallback() {
	synchronized (mLock) {
	return mOnStateChangeCallback == null
	? Optional.empty()
	: Optional.of(mOnStateChangeCallback);
	}
	}

	/**
	* Sets update engine status update callback. Value of {@code status} will
	* be one of the values from {@link UpdateEngine.UpdateStatusConstants}.
	*
	* @param onStatusUpdateCallback a callback with parameter {@code status}.
	*/
	public void setOnEngineStatusUpdateCallback(IntConsumer onStatusUpdateCallback) {
	synchronized (mLock) {
	this.mOnEngineStatusUpdateCallback = onStatusUpdateCallback;
	}
	}

	private Optional<IntConsumer> getOnEngineStatusUpdateCallback() {
	synchronized (mLock) {
	return mOnEngineStatusUpdateCallback == null
	? Optional.empty()
	: Optional.of(mOnEngineStatusUpdateCallback);
	}
	}

	/**
	* Sets update engine payload application complete callback. Value of {@code errorCode} will
	* be one of the values from {@link UpdateEngine.ErrorCodeConstants}.
	*
	* @param onComplete a callback with parameter {@code errorCode}.
	*/
	public void setOnEngineCompleteCallback(IntConsumer onComplete) {
	synchronized (mLock) {
	this.mOnEngineCompleteCallback = onComplete;
	}
	}

	private Optional<IntConsumer> getOnEngineCompleteCallback() {
	synchronized (mLock) {
	return mOnEngineCompleteCallback == null
	? Optional.empty()
	: Optional.of(mOnEngineCompleteCallback);
	}
	}

	/**
	* Sets progress update callback. Progress is a number from {@code 0.0} to {@code 1.0}.
	*
	* @param onProgressCallback a callback with parameter {@code progress}.
	*/
	public void setOnProgressUpdateCallback(DoubleConsumer onProgressCallback) {
	synchronized (mLock) {
	this.mOnProgressUpdateCallback = onProgressCallback;
	}
	}

	private Optional<DoubleConsumer> getOnProgressUpdateCallback() {
	synchronized (mLock) {
	return mOnProgressUpdateCallback == null
	? Optional.empty()
	: Optional.of(mOnProgressUpdateCallback);
	}
	}

	/**
	* Updates {@link this.mState} and if state is changed,
	* it also notifies {@link this.mOnStateChangeCallback}.
	*/
	private void setUpdaterState(int updaterState) {
	int previousState = mState.get();
	mState.set(updaterState);
	if (previousState != updaterState) {
	getOnStateChangeCallback().ifPresent(callback -> callback.accept(updaterState));
	}
	}

	/**
	* Requests update engine to stop any ongoing update. If an update has been applied,
	* leave it as is.
	*
	* <p>Sometimes it's possible that the
	* update engine would throw an error when the method is called, and the only way to
	* handle it is to catch the exception.</p>
	*/
	public void cancelRunningUpdate() {
	try {
	mUpdateEngine.cancel();
	setUpdaterState(UpdaterStates.IDLE);
	} catch (Exception e) {
	Log.w(TAG, "UpdateEngine failed to stop the ongoing update", e);
	}
	}

	/**
	* Resets update engine to IDLE state. If an update has been applied it reverts it.
	*
	* <p>Sometimes it's possible that the
	* update engine would throw an error when the method is called, and the only way to
	* handle it is to catch the exception.</p>
	*/
	public void resetUpdate() {
	try {
	mUpdateEngine.resetStatus();
	setUpdaterState(UpdaterStates.IDLE);
	} catch (Exception e) {
	Log.w(TAG, "UpdateEngine failed to reset the update", e);
	}
	}

	/**
	* Applies the given update.
	*
	* <p>UpdateEngine works asynchronously. This method doesn't wait until
	* end of the update.</p>
	*/
	public void applyUpdate(Context context, UpdateConfig config) {
	mEngineErrorCode.set(UpdateEngineErrorCodes.UNKNOWN);
	setUpdaterState(UpdaterStates.RUNNING);

	if (!config.getAbConfig().getForceSwitchSlot()) {
	mManualSwitchSlotRequired.set(true);
	} else {
	mManualSwitchSlotRequired.set(false);
	}

	if (config.getInstallType() == UpdateConfig.AB_INSTALL_TYPE_NON_STREAMING) {
	applyAbNonStreamingUpdate(config);
	} else {
	applyAbStreamingUpdate(context, config);
	}
	}

	private void applyAbNonStreamingUpdate(UpdateConfig config) {
	List<String> extraProperties = prepareExtraProperties(config);

	PayloadSpec payload;
	try {
	payload = mPayloadSpecs.forNonStreaming(config.getUpdatePackageFile());
	} catch (IOException e) {
	Log.e(TAG, "Error creating payload spec", e);
	setUpdaterState(UpdaterStates.ERROR);
	return;
	}
	updateEngineApplyPayload(payload, extraProperties);
	}

	private void applyAbStreamingUpdate(Context context, UpdateConfig config) {
	List<String> extraProperties = prepareExtraProperties(config);

	Log.d(TAG, "Starting PrepareStreamingService");
	PrepareStreamingService.startService(context, config, (code, payloadSpec) -> {
	if (code == PrepareStreamingService.RESULT_CODE_SUCCESS) {
	extraProperties.add("USER_AGENT=" + HTTP_USER_AGENT);
	config.getStreamingMetadata()
	.getAuthorization()
	.ifPresent(s -> extraProperties.add("AUTHORIZATION=" + s));
	updateEngineApplyPayload(payloadSpec, extraProperties);
	} else {
	Log.e(TAG, "PrepareStreamingService failed, result code is " + code);
	setUpdaterState(UpdaterStates.ERROR);
	}
	});
	}

	private List<String> prepareExtraProperties(UpdateConfig config) {
	List<String> extraProperties = new ArrayList<>();

	if (!config.getAbConfig().getForceSwitchSlot()) {
	// Disable switch slot on reboot, which is enabled by default.
	// User will enable it manually by clicking "Switch Slot" button on the screen.
	extraProperties.add(UpdateEngineProperties.PROPERTY_DISABLE_SWITCH_SLOT_ON_REBOOT);
	}
	return extraProperties;
	}

	/**
	* Applies given payload.
	*
	* <p>UpdateEngine works asynchronously. This method doesn't wait until
	* end of the update.</p>
	*
	* <p>It's possible that the update engine throws a generic error, such as upon seeing invalid
	* payload properties (which come from OTA packages), or failing to set up the network
	* with the given id.</p>
	*
	* @param payloadSpec contains url, offset and size to {@code PAYLOAD_BINARY_FILE_NAME}
	* @param extraProperties additional properties to pass to {@link UpdateEngine#applyPayload}
	*/
	private void updateEngineApplyPayload(PayloadSpec payloadSpec, List<String> extraProperties) {
	mLastPayloadSpec = payloadSpec;

	ArrayList<String> properties = new ArrayList<>(payloadSpec.getProperties());
	if (extraProperties != null) {
	properties.addAll(extraProperties);
	}
	try {
	mUpdateEngine.applyPayload(
	payloadSpec.getUrl(),
	payloadSpec.getOffset(),
	payloadSpec.getSize(),
	properties.toArray(new String[0]));
	} catch (Exception e) {
	Log.e(TAG, "UpdateEngine failed to apply the update", e);
	setUpdaterState(UpdaterStates.ERROR);
	}
	}

	/**
	* Sets the new slot that has the updated partitions as the active slot,
	* which device will boot into next time.
	* This method is only supposed to be called after the payload is applied.
	*
	* Invoking {@link UpdateEngine#applyPayload} with the same payload url, offset, size
	* and payload metadata headers doesn't trigger new update. It can be used to just switch
	* active A/B slot.
	*
	* {@link UpdateEngine#applyPayload} might take several seconds to finish, and it will
	* invoke callbacks {@link this#onStatusUpdate} and {@link this#onPayloadApplicationComplete)}.
	*/
	public void setSwitchSlotOnReboot() {
	Log.d(TAG, "setSwitchSlotOnReboot invoked");
	List<String> extraProperties = new ArrayList<>();
	// PROPERTY_SKIP_POST_INSTALL should be passed on to skip post-installation hooks.
	extraProperties.add(UpdateEngineProperties.PROPERTY_SKIP_POST_INSTALL);
	// It sets property SWITCH_SLOT_ON_REBOOT=1 by default.
	// HTTP headers are not required, UpdateEngine is not expected to stream payload.
	updateEngineApplyPayload(mLastPayloadSpec, extraProperties);
	}

	private void onStatusUpdate(int status, float progress) {
	int previousStatus = mUpdateEngineStatus.get();
	mUpdateEngineStatus.set(status);
	mProgress.set(progress);

	getOnProgressUpdateCallback().ifPresent(callback -> callback.accept(progress));

	if (previousStatus != status) {
	getOnEngineStatusUpdateCallback().ifPresent(callback -> callback.accept(status));
	}
	}

	private void onPayloadApplicationComplete(int errorCode) {
	Log.d(TAG, "onPayloadApplicationComplete invoked, errorCode=" + errorCode);
	mEngineErrorCode.set(errorCode);
	if (errorCode == UpdateEngine.ErrorCodeConstants.SUCCESS
	\|\| errorCode == UpdateEngineErrorCodes.UPDATED_BUT_NOT_ACTIVE) {
	setUpdaterState(UpdaterStates.FINISHED);
	} else if (errorCode != UpdateEngineErrorCodes.USER_CANCELLED) {
	setUpdaterState(UpdaterStates.ERROR);
	}

	getOnEngineCompleteCallback()
	.ifPresent(callback -> callback.accept(errorCode));
	}

	/**
	* Helper class to delegate {@code update_engine} callbacks to UpdateManager
	*/
	class UpdateEngineCallbackImpl extends UpdateEngineCallback {
	@Override
	public void onStatusUpdate(int status, float percent) {
	UpdateManager.this.onStatusUpdate(status, percent);
	}

	@Override
	public void onPayloadApplicationComplete(int errorCode) {
	UpdateManager.this.onPayloadApplicationComplete(errorCode);
	}
	}

	}