/*

* Copyright (C) 2007 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 android . os ;

import android . Manifest ;

import android . annotation . NonNull ;

import android . annotation . RequiresPermission ;

import android . annotation . SuppressAutoDoc ;

import android . annotation . SystemApi ;

import android . annotation . TestApi ;

import android . app . ActivityThread ;

import android . app . Application ;

import android . compat . annotation . UnsupportedAppUsage ;

import android . content . Context ;

import android . sysprop . TelephonyProperties ;

import android . text . TextUtils ;

import android . util . Slog ;

import android . view . View ;

import dalvik . system . VMRuntime ;

import java . util . ArrayList ;

import java . util . List ;

import java . util . Objects ;

import java . util . stream . Collectors ;

/**

* Information about the current build, extracted from system properties.

*/

public class Build {

private static final String TAG = "Build" ;

/** Value used for when a build property is unknown. */

public static final String UNKNOWN = "unknown" ;

/** Either a changelist number, or a label like "M4-rc20". */

public static final String ID = getString ( "ro.build.id" );

/** A build ID string meant for displaying to the user */

public static final String DISPLAY = getString ( "ro.build.display.id" );

/** The name of the overall product. */

public static final String PRODUCT = getString ( "ro.product.name" );

/** The name of the industrial design. */

public static final String DEVICE = getString ( "ro.product.device" );

/** The name of the underlying board, like "goldfish". */

public static final String BOARD = getString ( "ro.product.board" );

/**

* The name of the instruction set (CPU type + ABI convention) of native code.

*

* @deprecated Use {@link #SUPPORTED_ABIS} instead.

*/

@Deprecated

public static final String CPU_ABI ;

/**

* The name of the second instruction set (CPU type + ABI convention) of native code.

*

* @deprecated Use {@link #SUPPORTED_ABIS} instead.

*/

@Deprecated

public static final String CPU_ABI2 ;

/** The manufacturer of the product/hardware. */

public static final String MANUFACTURER = getString ( "ro.product.manufacturer" );

/** The consumer-visible brand with which the product/hardware will be associated, if any. */

public static final String BRAND = getString ( "ro.product.brand" );

/** The end-user-visible name for the end product. */

public static final String MODEL = getString ( "ro.product.model" );

/** The system bootloader version number. */

public static final String BOOTLOADER = getString ( "ro.bootloader" );

/**

* The radio firmware version number.

*

* @deprecated The radio firmware version is frequently not

* available when this class is initialized, leading to a blank or

* "unknown" value for this string. Use

* {@link #getRadioVersion} instead.

*/

@Deprecated

public static final String RADIO = joinListOrElse (

TelephonyProperties . baseband_version (), UNKNOWN );

/** The name of the hardware (from the kernel command line or /proc). */

public static final String HARDWARE = getString ( "ro.hardware" );

/**

* The hardware variant (SKU), if available.

*/

@NonNull

public static final String SKU = getString ( "ro.boot.hardware.sku" );

/**

* Whether this build was for an emulator device.

* @hide

*/

@UnsupportedAppUsage

@TestApi

public static final boolean IS_EMULATOR = getString ( "ro.kernel.qemu" ). equals ( "1" );

/**

* A hardware serial number, if available. Alphanumeric only, case-insensitive.

* This field is always set to {@link Build#UNKNOWN}.

*

* @deprecated Use {@link #getSerial()} instead.

**/

@Deprecated

// IMPORTANT: This field should be initialized via a function call to

// prevent its value being inlined in the app during compilation because

// we will later set it to the value based on the app's target SDK.

public static final String SERIAL = getString ( "no.such.thing" );

/**

* Gets the hardware serial number, if available.

*

* <p class="note"><b>Note:</b> Root access may allow you to modify device identifiers, such as

* the hardware serial number. If you change these identifiers, you can use

* <a href="/training/articles/security-key-attestation.html">key attestation</a> to obtain

* proof of the device's original identifiers.

*

* <p>Starting with API level 29, persistent device identifiers are guarded behind additional

* restrictions, and apps are recommended to use resettable identifiers (see <a

* href="c"> Best practices for unique identifiers</a>). This method can be invoked if one of

* the following requirements is met:

* <ul>

* <li>If the calling app has been granted the READ_PRIVILEGED_PHONE_STATE permission; this

* is a privileged permission that can only be granted to apps preloaded on the device.

* <li>If the calling app is the device or profile owner and has been granted the

* {@link Manifest.permission#READ_PHONE_STATE} permission. The profile owner is an app that

* owns a managed profile on the device; for more details see <a

* href="https://developer.android.com/work/managed-profiles">Work profiles</a>.

* Profile owner access is deprecated and will be removed in a future release.

* <li>If the calling app has carrier privileges (see {@link

* android.telephony.TelephonyManager#hasCarrierPrivileges}) on any active subscription.

* <li>If the calling app is the default SMS role holder (see {@link

* android.app.role.RoleManager#isRoleHeld(String)}).

* </ul>

*

* <p>If the calling app does not meet one of these requirements then this method will behave

* as follows:

*

* <ul>

* <li>If the calling app's target SDK is API level 28 or lower and the app has the

* READ_PHONE_STATE permission then {@link Build#UNKNOWN} is returned.</li>

* <li>If the calling app's target SDK is API level 28 or lower and the app does not have

* the READ_PHONE_STATE permission, or if the calling app is targeting API level 29 or

* higher, then a SecurityException is thrown.</li>

* </ul>

*

* @return The serial number if specified.

*/

@SuppressAutoDoc // No support for device / profile owner.

@RequiresPermission ( Manifest . permission . READ_PRIVILEGED_PHONE_STATE )

public static String getSerial () {

IDeviceIdentifiersPolicyService service = IDeviceIdentifiersPolicyService . Stub

. asInterface ( ServiceManager . getService ( Context . DEVICE_IDENTIFIERS_SERVICE ));

try {

Application application = ActivityThread . currentApplication ();

String callingPackage = application != null ? application . getPackageName () : null ;

return service . getSerialForPackage ( callingPackage , null );

} catch ( RemoteException e ) {

e . rethrowFromSystemServer ();

}

return UNKNOWN ;

}

/**

* An ordered list of ABIs supported by this device. The most preferred ABI is the first

* element in the list.

*

* See {@link #SUPPORTED_32_BIT_ABIS} and {@link #SUPPORTED_64_BIT_ABIS}.

*/

public static final String [] SUPPORTED_ABIS = getStringList ( "ro.product.cpu.abilist" , "," );

/**

* An ordered list of <b>32 bit</b> ABIs supported by this device. The most preferred ABI

* is the first element in the list.

*

* See {@link #SUPPORTED_ABIS} and {@link #SUPPORTED_64_BIT_ABIS}.

*/

public static final String [] SUPPORTED_32_BIT_ABIS =

getStringList ( "ro.product.cpu.abilist32" , "," );

/**

* An ordered list of <b>64 bit</b> ABIs supported by this device. The most preferred ABI

* is the first element in the list.

*

* See {@link #SUPPORTED_ABIS} and {@link #SUPPORTED_32_BIT_ABIS}.

*/

public static final String [] SUPPORTED_64_BIT_ABIS =

getStringList ( "ro.product.cpu.abilist64" , "," );

/** {@hide} */

@TestApi

public static boolean is64BitAbi ( String abi ) {

return VMRuntime . is64BitAbi ( abi );

}

static {

/*

* Adjusts CPU_ABI and CPU_ABI2 depending on whether or not a given process is 64 bit.

* 32 bit processes will always see 32 bit ABIs in these fields for backward

* compatibility.

*/

final String [] abiList ;

if ( VMRuntime . getRuntime (). is64Bit ()) {

abiList = SUPPORTED_64_BIT_ABIS ;

} else {

abiList = SUPPORTED_32_BIT_ABIS ;

}

CPU_ABI = abiList [ 0 ];

if ( abiList . length > 1 ) {

CPU_ABI2 = abiList [ 1 ];

} else {

CPU_ABI2 = "" ;

}

}

/** Various version strings. */

public static class VERSION {

/**

* The internal value used by the underlying source control to

* represent this build. E.g., a perforce changelist number

* or a git hash.

*/

public static final String INCREMENTAL = getString ( "ro.build.version.incremental" );

/**

* The user-visible version string. E.g., "1.0" or "3.4b5" or "bananas".

*

* This field is an opaque string. Do not assume that its value

* has any particular structure or that values of RELEASE from

* different releases can be somehow ordered.

*/

public static final String RELEASE = getString ( "ro.build.version.release" );

/**

* The version string we show to the user; may be {@link #RELEASE} or

* {@link #CODENAME} if not a final release build.

*/

@NonNull public static final String RELEASE_OR_CODENAME = getString (

"ro.build.version.release_or_codename" );

/**

* The base OS build the product is based on.

*/

public static final String BASE_OS = SystemProperties . get ( "ro.build.version.base_os" , "" );

/**

* The user-visible security patch level. This value represents the date when the device

* most recently applied a security patch.

*/

public static final String SECURITY_PATCH = SystemProperties . get (

"ro.build.version.security_patch" , "" );

/**

* The user-visible SDK version of the framework in its raw String

* representation; use {@link #SDK_INT} instead.

*

* @deprecated Use {@link #SDK_INT} to easily get this as an integer.

*/

@Deprecated

public static final String SDK = getString ( "ro.build.version.sdk" );

/**

* The SDK version of the software currently running on this hardware

* device. This value never changes while a device is booted, but it may

* increase when the hardware manufacturer provides an OTA update.

* <p>

* Possible values are defined in {@link Build.VERSION_CODES}.

*/

public static final int SDK_INT = SystemProperties . getInt (

"ro.build.version.sdk" , 0 );

/**

* The SDK version of the software that <em>initially</em> shipped on

* this hardware device. It <em>never</em> changes during the lifetime

* of the device, even when {@link #SDK_INT} increases due to an OTA

* update.

* <p>

* Possible values are defined in {@link Build.VERSION_CODES}.

*

* @see #SDK_INT

* @hide

*/

@TestApi

public static final int FIRST_SDK_INT = SystemProperties

. getInt ( "ro.product.first_api_level" , 0 );

/**

* The developer preview revision of a prerelease SDK. This value will always

* be <code>0</code> on production platform builds/devices.

*

* <p>When this value is nonzero, any new API added since the last

* officially published {@link #SDK_INT API level} is only guaranteed to be present

* on that specific preview revision. For example, an API <code>Activity.fooBar()</code>

* might be present in preview revision 1 but renamed or removed entirely in

* preview revision 2, which may cause an app attempting to call it to crash

* at runtime.</p>

*

* <p>Experimental apps targeting preview APIs should check this value for

* equality (<code>==</code>) with the preview SDK revision they were built for

* before using any prerelease platform APIs. Apps that detect a preview SDK revision

* other than the specific one they expect should fall back to using APIs from

* the previously published API level only to avoid unwanted runtime exceptions.

* </p>

*/

public static final int PREVIEW_SDK_INT = SystemProperties . getInt (

"ro.build.version.preview_sdk" , 0 );

/**

* The SDK fingerprint for a given prerelease SDK. This value will always be

* {@code REL} on production platform builds/devices.

*

* <p>When this value is not {@code REL}, it contains a string fingerprint of the API

* surface exposed by the preview SDK. Preview platforms with different API surfaces

* will have different {@code PREVIEW_SDK_FINGERPRINT}.

*

* <p>This attribute is intended for use by installers for finer grained targeting of

* packages. Applications targeting preview APIs should not use this field and should

* instead use {@code PREVIEW_SDK_INT} or use reflection or other runtime checks to

* detect the presence of an API or guard themselves against unexpected runtime

* behavior.

*

* @hide

*/

@SystemApi

@NonNull public static final String PREVIEW_SDK_FINGERPRINT = SystemProperties . get (

"ro.build.version.preview_sdk_fingerprint" , "REL" );

/**

* The current development codename, or the string "REL" if this is

* a release build.

*/

public static final String CODENAME = getString ( "ro.build.version.codename" );

private static final String [] ALL_CODENAMES

= getStringList ( "ro.build.version.all_codenames" , "," );

/**

* @hide

*/

@UnsupportedAppUsage

@TestApi

public static final String [] ACTIVE_CODENAMES = "REL" . equals ( ALL_CODENAMES [ 0 ])

? new String [ 0 ] : ALL_CODENAMES ;

/**

* The SDK version to use when accessing resources.

* Use the current SDK version code. For every active development codename

* we are operating under, we bump the assumed resource platform version by 1.

* @hide

*/

@TestApi

public static final int RESOURCES_SDK_INT = SDK_INT + ACTIVE_CODENAMES . length ;

/**

* The current lowest supported value of app target SDK. Applications targeting

* lower values may not function on devices running this SDK version. Its possible

* values are defined in {@link Build.VERSION_CODES}.

*

* @hide

*/

public static final int MIN_SUPPORTED_TARGET_SDK_INT = SystemProperties . getInt (

"ro.build.version.min_supported_target_sdk" , 0 );

}

/**

* Enumeration of the currently known SDK version codes. These are the

* values that can be found in {@link VERSION#SDK}. Version numbers

* increment monotonically with each official platform release.

*/

public static class VERSION_CODES {

/**

* Magic version number for a current development build, which has

* not yet turned into an official release.

*/

public static final int CUR_DEVELOPMENT = VMRuntime . SDK_VERSION_CUR_DEVELOPMENT ;

/**

* October 2008: The original, first, version of Android. Yay!

*/

public static final int BASE = 1 ;

/**

* February 2009: First Android update, officially called 1.1.

*/

public static final int BASE_1_1 = 2 ;

/**

* May 2009: Android 1.5.

*/

public static final int CUPCAKE = 3 ;

/**

* September 2009: Android 1.6.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li> They must explicitly request the

* {@link android.Manifest.permission#WRITE_EXTERNAL_STORAGE} permission to be

* able to modify the contents of the SD card. (Apps targeting

* earlier versions will always request the permission.)

* <li> They must explicitly request the

* {@link android.Manifest.permission#READ_PHONE_STATE} permission to be

* able to be able to retrieve phone state info. (Apps targeting

* earlier versions will always request the permission.)

* <li> They are assumed to support different screen densities and

* sizes. (Apps targeting earlier versions are assumed to only support

* medium density normal size screens unless otherwise indicated).

* They can still explicitly specify screen support either way with the

* supports-screens manifest tag.

* <li> {@link android.widget.TabHost} will use the new dark tab

* background design.

* </ul>

*/

public static final int DONUT = 4 ;

/**

* November 2009: Android 2.0

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li> The {@link android.app.Service#onStartCommand

* Service.onStartCommand} function will return the new

* {@link android.app.Service#START_STICKY} behavior instead of the

* old compatibility {@link android.app.Service#START_STICKY_COMPATIBILITY}.

* <li> The {@link android.app.Activity} class will now execute back

* key presses on the key up instead of key down, to be able to detect

* canceled presses from virtual keys.

* <li> The {@link android.widget.TabWidget} class will use a new color scheme

* for tabs. In the new scheme, the foreground tab has a medium gray background

* the background tabs have a dark gray background.

* </ul>

*/

public static final int ECLAIR = 5 ;

/**

* December 2009: Android 2.0.1

*/

public static final int ECLAIR_0_1 = 6 ;

/**

* January 2010: Android 2.1

*/

public static final int ECLAIR_MR1 = 7 ;

/**

* June 2010: Android 2.2

*/

public static final int FROYO = 8 ;

/**

* November 2010: Android 2.3

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li> The application's notification icons will be shown on the new

* dark status bar background, so must be visible in this situation.

* </ul>

*/

public static final int GINGERBREAD = 9 ;

/**

* February 2011: Android 2.3.3.

*/

public static final int GINGERBREAD_MR1 = 10 ;

/**

* February 2011: Android 3.0.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li> The default theme for applications is now dark holographic:

* {@link android.R.style#Theme_Holo}.

* <li> On large screen devices that do not have a physical menu

* button, the soft (compatibility) menu is disabled.

* <li> The activity lifecycle has changed slightly as per

* {@link android.app.Activity}.

* <li> An application will crash if it does not call through

* to the super implementation of its

* {@link android.app.Activity#onPause Activity.onPause()} method.

* <li> When an application requires a permission to access one of

* its components (activity, receiver, service, provider), this

* permission is no longer enforced when the application wants to

* access its own component. This means it can require a permission

* on a component that it does not itself hold and still access that

* component.

* <li> {@link android.content.Context#getSharedPreferences

* Context.getSharedPreferences()} will not automatically reload

* the preferences if they have changed on storage, unless

* {@link android.content.Context#MODE_MULTI_PROCESS} is used.

* <li> {@link android.view.ViewGroup#setMotionEventSplittingEnabled}

* will default to true.

* <li> {@link android.view.WindowManager.LayoutParams#FLAG_SPLIT_TOUCH}

* is enabled by default on windows.

* <li> {@link android.widget.PopupWindow#isSplitTouchEnabled()

* PopupWindow.isSplitTouchEnabled()} will return true by default.

* <li> {@link android.widget.GridView} and {@link android.widget.ListView}

* will use {@link android.view.View#setActivated View.setActivated}

* for selected items if they do not implement {@link android.widget.Checkable}.

* <li> {@link android.widget.Scroller} will be constructed with

* "flywheel" behavior enabled by default.

* </ul>

*/

public static final int HONEYCOMB = 11 ;

/**

* May 2011: Android 3.1.

*/

public static final int HONEYCOMB_MR1 = 12 ;

/**

* June 2011: Android 3.2.

*

* <p>Update to Honeycomb MR1 to support 7 inch tablets, improve

* screen compatibility mode, etc.</p>

*

* <p>As of this version, applications that don't say whether they

* support XLARGE screens will be assumed to do so only if they target

* {@link #HONEYCOMB} or later; it had been {@link #GINGERBREAD} or

* later. Applications that don't support a screen size at least as

* large as the current screen will provide the user with a UI to

* switch them in to screen size compatibility mode.</p>

*

* <p>This version introduces new screen size resource qualifiers

* based on the screen size in dp: see

* {@link android.content.res.Configuration#screenWidthDp},

* {@link android.content.res.Configuration#screenHeightDp}, and

* {@link android.content.res.Configuration#smallestScreenWidthDp}.

* Supplying these in <supports-screens> as per

* {@link android.content.pm.ApplicationInfo#requiresSmallestWidthDp},

* {@link android.content.pm.ApplicationInfo#compatibleWidthLimitDp}, and

* {@link android.content.pm.ApplicationInfo#largestWidthLimitDp} is

* preferred over the older screen size buckets and for older devices

* the appropriate buckets will be inferred from them.</p>

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li><p>New {@link android.content.pm.PackageManager#FEATURE_SCREEN_PORTRAIT}

* and {@link android.content.pm.PackageManager#FEATURE_SCREEN_LANDSCAPE}

* features were introduced in this release. Applications that target

* previous platform versions are assumed to require both portrait and

* landscape support in the device; when targeting Honeycomb MR1 or

* greater the application is responsible for specifying any specific

* orientation it requires.</p>

* <li><p>{@link android.os.AsyncTask} will use the serial executor

* by default when calling {@link android.os.AsyncTask#execute}.</p>

* <li><p>{@link android.content.pm.ActivityInfo#configChanges

* ActivityInfo.configChanges} will have the

* {@link android.content.pm.ActivityInfo#CONFIG_SCREEN_SIZE} and

* {@link android.content.pm.ActivityInfo#CONFIG_SMALLEST_SCREEN_SIZE}

* bits set; these need to be cleared for older applications because

* some developers have done absolute comparisons against this value

* instead of correctly masking the bits they are interested in.

* </ul>

*/

public static final int HONEYCOMB_MR2 = 13 ;

/**

* October 2011: Android 4.0.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li> For devices without a dedicated menu key, the software compatibility

* menu key will not be shown even on phones. By targeting Ice Cream Sandwich

* or later, your UI must always have its own menu UI affordance if needed,

* on both tablets and phones. The ActionBar will take care of this for you.

* <li> 2d drawing hardware acceleration is now turned on by default.

* You can use

* {@link android.R.attr#hardwareAccelerated android:hardwareAccelerated}

* to turn it off if needed, although this is strongly discouraged since

* it will result in poor performance on larger screen devices.

* <li> The default theme for applications is now the "device default" theme:

* {@link android.R.style#Theme_DeviceDefault}. This may be the

* holo dark theme or a different dark theme defined by the specific device.

* The {@link android.R.style#Theme_Holo} family must not be modified

* for a device to be considered compatible. Applications that explicitly

* request a theme from the Holo family will be guaranteed that these themes

* will not change character within the same platform version. Applications

* that wish to blend in with the device should use a theme from the

* {@link android.R.style#Theme_DeviceDefault} family.

* <li> Managed cursors can now throw an exception if you directly close

* the cursor yourself without stopping the management of it; previously failures

* would be silently ignored.

* <li> The fadingEdge attribute on views will be ignored (fading edges is no

* longer a standard part of the UI). A new requiresFadingEdge attribute allows

* applications to still force fading edges on for special cases.

* <li> {@link android.content.Context#bindService Context.bindService()}

* will not automatically add in {@link android.content.Context#BIND_WAIVE_PRIORITY}.

* <li> App Widgets will have standard padding automatically added around

* them, rather than relying on the padding being baked into the widget itself.

* <li> An exception will be thrown if you try to change the type of a

* window after it has been added to the window manager. Previously this

* would result in random incorrect behavior.

* <li> {@link android.view.animation.AnimationSet} will parse out

* the duration, fillBefore, fillAfter, repeatMode, and startOffset

* XML attributes that are defined.

* <li> {@link android.app.ActionBar#setHomeButtonEnabled

* ActionBar.setHomeButtonEnabled()} is false by default.

* </ul>

*/

public static final int ICE_CREAM_SANDWICH = 14 ;

/**

* December 2011: Android 4.0.3.

*/

public static final int ICE_CREAM_SANDWICH_MR1 = 15 ;

/**

* June 2012: Android 4.1.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li> You must explicitly request the {@link android.Manifest.permission#READ_CALL_LOG}

* and/or {@link android.Manifest.permission#WRITE_CALL_LOG} permissions;

* access to the call log is no longer implicitly provided through

* {@link android.Manifest.permission#READ_CONTACTS} and

* {@link android.Manifest.permission#WRITE_CONTACTS}.

* <li> {@link android.widget.RemoteViews} will throw an exception if

* setting an onClick handler for views being generated by a

* {@link android.widget.RemoteViewsService} for a collection container;

* previously this just resulted in a warning log message.

* <li> New {@link android.app.ActionBar} policy for embedded tabs:

* embedded tabs are now always stacked in the action bar when in portrait

* mode, regardless of the size of the screen.

* <li> {@link android.webkit.WebSettings#setAllowFileAccessFromFileURLs(boolean)

* WebSettings.setAllowFileAccessFromFileURLs} and

* {@link android.webkit.WebSettings#setAllowUniversalAccessFromFileURLs(boolean)

* WebSettings.setAllowUniversalAccessFromFileURLs} default to false.

* <li> Calls to {@link android.content.pm.PackageManager#setComponentEnabledSetting

* PackageManager.setComponentEnabledSetting} will now throw an

* IllegalArgumentException if the given component class name does not

* exist in the application's manifest.

* <li> {@link android.nfc.NfcAdapter#setNdefPushMessage

* NfcAdapter.setNdefPushMessage},

* {@link android.nfc.NfcAdapter#setNdefPushMessageCallback

* NfcAdapter.setNdefPushMessageCallback} and

* {@link android.nfc.NfcAdapter#setOnNdefPushCompleteCallback

* NfcAdapter.setOnNdefPushCompleteCallback} will throw

* IllegalStateException if called after the Activity has been destroyed.

* <li> Accessibility services must require the new

* {@link android.Manifest.permission#BIND_ACCESSIBILITY_SERVICE} permission or

* they will not be available for use.

* <li> {@link android.accessibilityservice.AccessibilityServiceInfo#FLAG_INCLUDE_NOT_IMPORTANT_VIEWS

* AccessibilityServiceInfo.FLAG_INCLUDE_NOT_IMPORTANT_VIEWS} must be set

* for unimportant views to be included in queries.

* </ul>

*/

public static final int JELLY_BEAN = 16 ;

/**

* November 2012: Android 4.2, Moar jelly beans!

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li>Content Providers: The default value of {@code android:exported} is now

* {@code false}. See

* <a href="{@docRoot}guide/topics/manifest/provider-element.html#exported">

* the android:exported section</a> in the provider documentation for more details.</li>

* <li>{@link android.view.View#getLayoutDirection() View.getLayoutDirection()}

* can return different values than {@link android.view.View#LAYOUT_DIRECTION_LTR}

* based on the locale etc.

* <li> {@link android.webkit.WebView#addJavascriptInterface(Object, String)

* WebView.addJavascriptInterface} requires explicit annotations on methods

* for them to be accessible from Javascript.

* </ul>

*/

public static final int JELLY_BEAN_MR1 = 17 ;

/**

* July 2013: Android 4.3, the revenge of the beans.

*/

public static final int JELLY_BEAN_MR2 = 18 ;

/**

* October 2013: Android 4.4, KitKat, another tasty treat.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior. For more information about this release, see the

* <a href="/about/versions/kitkat/">Android KitKat overview</a>.</p>

* <ul>

* <li> The default result of

* {@link android.preference.PreferenceActivity#isValidFragment(String)

* PreferenceActivity.isValueFragment} becomes false instead of true.</li>

* <li> In {@link android.webkit.WebView}, apps targeting earlier versions will have

* JS URLs evaluated directly and any result of the evaluation will not replace

* the current page content. Apps targetting KITKAT or later that load a JS URL will

* have the result of that URL replace the content of the current page</li>

* <li> {@link android.app.AlarmManager#set AlarmManager.set} becomes interpreted as

* an inexact value, to give the system more flexibility in scheduling alarms.</li>

* <li> {@link android.content.Context#getSharedPreferences(String, int)

* Context.getSharedPreferences} no longer allows a null name.</li>

* <li> {@link android.widget.RelativeLayout} changes to compute wrapped content

* margins correctly.</li>

* <li> {@link android.app.ActionBar}'s window content overlay is allowed to be

* drawn.</li>

* <li>The {@link android.Manifest.permission#READ_EXTERNAL_STORAGE}

* permission is now always enforced.</li>

* <li>Access to package-specific external storage directories belonging

* to the calling app no longer requires the

* {@link android.Manifest.permission#READ_EXTERNAL_STORAGE} or

* {@link android.Manifest.permission#WRITE_EXTERNAL_STORAGE}

* permissions.</li>

* </ul>

*/

public static final int KITKAT = 19 ;

/**

* June 2014: Android 4.4W. KitKat for watches, snacks on the run.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior:</p>

* <ul>

* <li>{@link android.app.AlertDialog} might not have a default background if the theme does

* not specify one.</li>

* </ul>

*/

public static final int KITKAT_WATCH = 20 ;

/**

* Temporary until we completely switch to {@link #LOLLIPOP}.

* @hide

*/

public static final int L = 21 ;

/**

* November 2014: Lollipop. A flat one with beautiful shadows. But still tasty.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior. For more information about this release, see the

* <a href="/about/versions/lollipop/">Android Lollipop overview</a>.</p>

* <ul>

* <li> {@link android.content.Context#bindService Context.bindService} now

* requires an explicit Intent, and will throw an exception if given an implicit

* Intent.</li>

* <li> {@link android.app.Notification.Builder Notification.Builder} will

* not have the colors of their various notification elements adjusted to better

* match the new material design look.</li>

* <li> {@link android.os.Message} will validate that a message is not currently

* in use when it is recycled.</li>

* <li> Hardware accelerated drawing in windows will be enabled automatically

* in most places.</li>

* <li> {@link android.widget.Spinner} throws an exception if attaching an

* adapter with more than one item type.</li>

* <li> If the app is a launcher, the launcher will be available to the user

* even when they are using corporate profiles (which requires that the app

* use {@link android.content.pm.LauncherApps} to correctly populate its

* apps UI).</li>

* <li> Calling {@link android.app.Service#stopForeground Service.stopForeground}

* with removeNotification false will modify the still posted notification so that

* it is no longer forced to be ongoing.</li>

* <li> A {@link android.service.dreams.DreamService} must require the

* {@link android.Manifest.permission#BIND_DREAM_SERVICE} permission to be usable.</li>

* </ul>

*/

public static final int LOLLIPOP = 21 ;

/**

* March 2015: Lollipop with an extra sugar coating on the outside!

* For more information about this release, see the

* <a href="/about/versions/android-5.1">Android 5.1 APIs</a>.

*/

public static final int LOLLIPOP_MR1 = 22 ;

/**

* M is for Marshmallow!

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior. For more information about this release, see the

* <a href="/about/versions/marshmallow/">Android 6.0 Marshmallow overview</a>.</p>

* <ul>

* <li> Runtime permissions. Dangerous permissions are no longer granted at

* install time, but must be requested by the application at runtime through

* {@link android.app.Activity#requestPermissions}.</li>

* <li> Bluetooth and Wi-Fi scanning now requires holding the location permission.</li>

* <li> {@link android.app.AlarmManager#setTimeZone AlarmManager.setTimeZone} will fail if

* the given timezone is non-Olson.</li>

* <li> Activity transitions will only return shared

* elements mapped in the returned view hierarchy back to the calling activity.</li>

* <li> {@link android.view.View} allows a number of behaviors that may break

* existing apps: Canvas throws an exception if restore() is called too many times,

* widgets may return a hint size when returning UNSPECIFIED measure specs, and it

* will respect the attributes {@link android.R.attr#foreground},

* {@link android.R.attr#foregroundGravity}, {@link android.R.attr#foregroundTint}, and

* {@link android.R.attr#foregroundTintMode}.</li>

* <li> {@link android.view.MotionEvent#getButtonState MotionEvent.getButtonState}

* will no longer report {@link android.view.MotionEvent#BUTTON_PRIMARY}

* and {@link android.view.MotionEvent#BUTTON_SECONDARY} as synonyms for

* {@link android.view.MotionEvent#BUTTON_STYLUS_PRIMARY} and

* {@link android.view.MotionEvent#BUTTON_STYLUS_SECONDARY}.</li>

* <li> {@link android.widget.ScrollView} now respects the layout param margins

* when measuring.</li>

* </ul>

*/

public static final int M = 23 ;

/**

* N is for Nougat.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior. For more information about this release, see

* the <a href="/about/versions/nougat/">Android Nougat overview</a>.</p>

* <ul>

* <li> {@link android.app.DownloadManager.Request#setAllowedNetworkTypes

* DownloadManager.Request.setAllowedNetworkTypes}

* will disable "allow over metered" when specifying only

* {@link android.app.DownloadManager.Request#NETWORK_WIFI}.</li>

* <li> {@link android.app.DownloadManager} no longer allows access to raw

* file paths.</li>

* <li> {@link android.app.Notification.Builder#setShowWhen

* Notification.Builder.setShowWhen}

* must be called explicitly to have the time shown, and various other changes in

* {@link android.app.Notification.Builder Notification.Builder} to how notifications

* are shown.</li>

* <li>{@link android.content.Context#MODE_WORLD_READABLE} and

* {@link android.content.Context#MODE_WORLD_WRITEABLE} are no longer supported.</li>

* <li>{@link android.os.FileUriExposedException} will be thrown to applications.</li>

* <li>Applications will see global drag and drops as per

* {@link android.view.View#DRAG_FLAG_GLOBAL}.</li>

* <li>{@link android.webkit.WebView#evaluateJavascript WebView.evaluateJavascript}

* will not persist state from an empty WebView.</li>

* <li>{@link android.animation.AnimatorSet} will not ignore calls to end() before

* start().</li>

* <li>{@link android.app.AlarmManager#cancel(android.app.PendingIntent)

* AlarmManager.cancel} will throw a NullPointerException if given a null operation.</li>

* <li>{@link android.app.FragmentManager} will ensure fragments have been created

* before being placed on the back stack.</li>

* <li>{@link android.app.FragmentManager} restores fragments in

* {@link android.app.Fragment#onCreate Fragment.onCreate} rather than after the

* method returns.</li>

* <li>{@link android.R.attr#resizeableActivity} defaults to true.</li>

* <li>{@link android.graphics.drawable.AnimatedVectorDrawable} throws exceptions when

* opening invalid VectorDrawable animations.</li>

* <li>{@link android.view.ViewGroup.MarginLayoutParams} will no longer be dropped

* when converting between some types of layout params (such as

* {@link android.widget.LinearLayout.LayoutParams LinearLayout.LayoutParams} to

* {@link android.widget.RelativeLayout.LayoutParams RelativeLayout.LayoutParams}).</li>

* <li>Your application processes will not be killed when the device density changes.</li>

* <li>Drag and drop. After a view receives the

* {@link android.view.DragEvent#ACTION_DRAG_ENTERED} event, when the drag shadow moves into

* a descendant view that can accept the data, the view receives the

* {@link android.view.DragEvent#ACTION_DRAG_EXITED} event and won’t receive

* {@link android.view.DragEvent#ACTION_DRAG_LOCATION} and

* {@link android.view.DragEvent#ACTION_DROP} events while the drag shadow is within that

* descendant view, even if the descendant view returns <code>false</code> from its handler

* for these events.</li>

* </ul>

*/

public static final int N = 24 ;

/**

* N MR1: Nougat++. For more information about this release, see

* <a href="/about/versions/nougat/android-7.1">Android 7.1 for

* Developers</a>.

*/

public static final int N_MR1 = 25 ;

/**

* O.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior. For more information about this release, see

* the <a href="/about/versions/oreo/">Android Oreo overview</a>.</p>

* <ul>

* <li><a href="{@docRoot}about/versions/oreo/background.html">Background execution limits</a>

* are applied to the application.</li>

* <li>The behavior of AccountManager's

* {@link android.accounts.AccountManager#getAccountsByType},

* {@link android.accounts.AccountManager#getAccountsByTypeAndFeatures}, and

* {@link android.accounts.AccountManager#hasFeatures} has changed as documented there.</li>

* <li>{@link android.app.ActivityManager.RunningAppProcessInfo#IMPORTANCE_PERCEPTIBLE_PRE_26}

* is now returned as

* {@link android.app.ActivityManager.RunningAppProcessInfo#IMPORTANCE_PERCEPTIBLE}.</li>

* <li>The {@link android.app.NotificationManager} now requires the use of notification

* channels.</li>

* <li>Changes to the strict mode that are set in

* {@link Application#onCreate Application.onCreate} will no longer be clobbered after

* that function returns.</li>

* <li>A shared library apk with native code will have that native code included in

* the library path of its clients.</li>

* <li>{@link android.content.Context#getSharedPreferences Context.getSharedPreferences}

* in credential encrypted storage will throw an exception before the user is unlocked.</li>

* <li>Attempting to retrieve a {@link Context#FINGERPRINT_SERVICE} on a device that

* does not support that feature will now throw a runtime exception.</li>

* <li>{@link android.app.Fragment} will stop any active view animations when

* the fragment is stopped.</li>

* <li>Some compatibility code in Resources that attempts to use the default Theme

* the app may be using will be turned off, requiring the app to explicitly request

* resources with the right theme.</li>

* <li>{@link android.content.ContentResolver#notifyChange ContentResolver.notifyChange} and

* {@link android.content.ContentResolver#registerContentObserver

* ContentResolver.registerContentObserver}

* will throw a SecurityException if the caller does not have permission to access

* the provider (or the provider doesn't exit); otherwise the call will be silently

* ignored.</li>

* <li>{@link android.hardware.camera2.CameraDevice#createCaptureRequest

* CameraDevice.createCaptureRequest} will enable

* {@link android.hardware.camera2.CaptureRequest#CONTROL_ENABLE_ZSL} by default for

* still image capture.</li>

* <li>WallpaperManager's {@link android.app.WallpaperManager#getWallpaperFile},

* {@link android.app.WallpaperManager#getDrawable},

* {@link android.app.WallpaperManager#getFastDrawable},

* {@link android.app.WallpaperManager#peekDrawable}, and

* {@link android.app.WallpaperManager#peekFastDrawable} will throw an exception

* if you can not access the wallpaper.</li>

* <li>The behavior of

* {@link android.hardware.usb.UsbDeviceConnection#requestWait UsbDeviceConnection.requestWait}

* is modified as per the documentation there.</li>

* <li>{@link StrictMode.VmPolicy.Builder#detectAll StrictMode.VmPolicy.Builder.detectAll}

* will also enable {@link StrictMode.VmPolicy.Builder#detectContentUriWithoutPermission}

* and {@link StrictMode.VmPolicy.Builder#detectUntaggedSockets}.</li>

* <li>{@link StrictMode.ThreadPolicy.Builder#detectAll StrictMode.ThreadPolicy.Builder.detectAll}

* will also enable {@link StrictMode.ThreadPolicy.Builder#detectUnbufferedIo}.</li>

* <li>{@link android.provider.DocumentsContract}'s various methods will throw failure

* exceptions back to the caller instead of returning null.

* <li>{@link View#hasFocusable View.hasFocusable} now includes auto-focusable views.</li>

* <li>{@link android.view.SurfaceView} will no longer always change the underlying

* Surface object when something about it changes; apps need to look at the current

* state of the object to determine which things they are interested in have changed.</li>

* <li>{@link android.view.WindowManager.LayoutParams#TYPE_APPLICATION_OVERLAY} must be

* used for overlay windows, other system overlay window types are not allowed.</li>

* <li>{@link android.view.ViewTreeObserver#addOnDrawListener

* ViewTreeObserver.addOnDrawListener} will throw an exception if called from within

* onDraw.</li>

* <li>{@link android.graphics.Canvas#setBitmap Canvas.setBitmap} will no longer preserve

* the current matrix and clip stack of the canvas.</li>

* <li>{@link android.widget.ListPopupWindow#setHeight ListPopupWindow.setHeight}

* will throw an exception if a negative height is supplied.</li>

* <li>{@link android.widget.TextView} will use internationalized input for numbers,

* dates, and times.</li>

* <li>{@link android.widget.Toast} must be used for showing toast windows; the toast

* window type can not be directly used.</li>

* <li>{@link android.net.wifi.WifiManager#getConnectionInfo WifiManager.getConnectionInfo}

* requires that the caller hold the location permission to return BSSID/SSID</li>

* <li>{@link android.net.wifi.p2p.WifiP2pManager#requestPeers WifiP2pManager.requestPeers}

* requires the caller hold the location permission.</li>

* <li>{@link android.R.attr#maxAspectRatio} defaults to 0, meaning there is no restriction

* on the app's maximum aspect ratio (so it can be stretched to fill larger screens).</li>

* <li>{@link android.R.attr#focusable} defaults to a new state ({@code auto}) where it will

* inherit the value of {@link android.R.attr#clickable} unless explicitly overridden.</li>

* <li>A default theme-appropriate focus-state highlight will be supplied to all Views

* which don't provide a focus-state drawable themselves. This can be disabled by setting

* {@link android.R.attr#defaultFocusHighlightEnabled} to false.</li>

* </ul>

*/

public static final int O = 26 ;

/**

* O MR1.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior. For more information about this release, see

* <a href="/about/versions/oreo/android-8.1">Android 8.1 features and

* APIs</a>.</p>

* <ul>

* <li>Apps exporting and linking to apk shared libraries must explicitly

* enumerate all signing certificates in a consistent order.</li>

* <li>{@link android.R.attr#screenOrientation} can not be used to request a fixed

* orientation if the associated activity is not fullscreen and opaque.</li>

* </ul>

*

*/

public static final int O_MR1 = 27 ;

/**

* P.

*

* <p>Applications targeting this or a later release will get these

* new changes in behavior. For more information about this release, see the

* <a href="/about/versions/pie/">Android 9 Pie overview</a>.</p>

* <ul>

* <li>{@link android.app.Service#startForeground Service.startForeground} requires

* that apps hold the permission

* {@link android.Manifest.permission#FOREGROUND_SERVICE}.</li>

* <li>{@link android.widget.LinearLayout} will always remeasure weighted children,

* even if there is no excess space.</li>

* </ul>

*

*/

public static final int P = 28 ;

/**

* Q.

* <p>

* <em>Why? Why, to give you a taste of your future, a preview of things

* to come. Con permiso, Capitan. The hall is rented, the orchestra

* engaged. It's now time to see if you can dance.</em>

*/

public static final int Q = 29 ;

/**

* R.

*/

public static final int R = 30 ;

}

/** The type of build, like "user" or "eng". */

public static final String TYPE = getString ( "ro.build.type" );

/** Comma-separated tags describing the build, like "unsigned,debug". */

public static final String TAGS = getString ( "ro.build.tags" );

/** A string that uniquely identifies this build. Do not attempt to parse this value. */

public static final String FINGERPRINT = deriveFingerprint ();

/**

* Some devices split the fingerprint components between multiple

* partitions, so we might derive the fingerprint at runtime.

*/

private static String deriveFingerprint () {

String finger = SystemProperties . get ( "ro.build.fingerprint" );

if ( TextUtils . isEmpty ( finger )) {

finger = getString ( "ro.product.brand" ) + '/' +

getString ( "ro.product.name" ) + '/' +

getString ( "ro.product.device" ) + ':' +

getString ( "ro.build.version.release" ) + '/' +

getString ( "ro.build.id" ) + '/' +

getString ( "ro.build.version.incremental" ) + ':' +

getString ( "ro.build.type" ) + '/' +

getString ( "ro.build.tags" );

}

return finger ;

}

/**

* Ensure that raw fingerprint system property is defined. If it was derived

* dynamically by {@link #deriveFingerprint()} this is where we push the

* derived value into the property service.

*

* @hide

*/

public static void ensureFingerprintProperty () {

if ( TextUtils . isEmpty ( SystemProperties . get ( "ro.build.fingerprint" ))) {

try {

SystemProperties . set ( "ro.build.fingerprint" , FINGERPRINT );

} catch ( IllegalArgumentException e ) {

Slog . e ( TAG , "Failed to set fingerprint property" , e );

}

}

}

/**

* True if Treble is enabled and required for this device.

*

* @hide

*/

public static final boolean IS_TREBLE_ENABLED =

SystemProperties . getBoolean ( "ro.treble.enabled" , false );

/**

* Verifies the current flash of the device is consistent with what

* was expected at build time.

*

* Treble devices will verify the Vendor Interface (VINTF). A device

* launched without Treble:

*

* 1) Checks that device fingerprint is defined and that it matches across

* various partitions.

* 2) Verifies radio and bootloader partitions are those expected in the build.

*

* @hide

*/

public static boolean isBuildConsistent () {

// Don't care on eng builds. Incremental build may trigger false negative.

if ( IS_ENG ) return true ;

if ( IS_TREBLE_ENABLED ) {

// If we can run this code, the device should already pass AVB.

// So, we don't need to check AVB here.

int result = VintfObject . verifyWithoutAvb ();

if ( result != 0 ) {

Slog . e ( TAG , "Vendor interface is incompatible, error="

+ String . valueOf ( result ));

}

return result == 0 ;

}

final String system = SystemProperties . get ( "ro.system.build.fingerprint" );

final String vendor = SystemProperties . get ( "ro.vendor.build.fingerprint" );

final String bootimage = SystemProperties . get ( "ro.bootimage.build.fingerprint" );

final String requiredBootloader = SystemProperties . get ( "ro.build.expect.bootloader" );

final String currentBootloader = SystemProperties . get ( "ro.bootloader" );

final String requiredRadio = SystemProperties . get ( "ro.build.expect.baseband" );

final String currentRadio = joinListOrElse (

TelephonyProperties . baseband_version (), "" );

if ( TextUtils . isEmpty ( system )) {

Slog . e ( TAG , "Required ro.system.build.fingerprint is empty!" );

return false ;

}

if (! TextUtils . isEmpty ( vendor )) {

if (! Objects . equals ( system , vendor )) {

Slog . e ( TAG , "Mismatched fingerprints; system reported " + system

+ " but vendor reported " + vendor );

return false ;

}

}

/* TODO: Figure out issue with checks failing

if (!TextUtils.isEmpty(bootimage)) {

if (!Objects.equals(system, bootimage)) {

Slog.e(TAG, "Mismatched fingerprints; system reported " + system

+ " but bootimage reported " + bootimage);

return false;

}

}

if (!TextUtils.isEmpty(requiredBootloader)) {

if (!Objects.equals(currentBootloader, requiredBootloader)) {

Slog.e(TAG, "Mismatched bootloader version: build requires " + requiredBootloader

+ " but runtime reports " + currentBootloader);

return false;

}

}

if (!TextUtils.isEmpty(requiredRadio)) {

if (!Objects.equals(currentRadio, requiredRadio)) {

Slog.e(TAG, "Mismatched radio version: build requires " + requiredRadio

+ " but runtime reports " + currentRadio);

return false;

}

}

*/

return true ;

}

/** Build information for a particular device partition. */

public static class Partition {

/** The name identifying the system partition. */

public static final String PARTITION_NAME_SYSTEM = "system" ;

private final String mName ;

private final String mFingerprint ;

private final long mTimeMs ;

private Partition ( String name , String fingerprint , long timeMs ) {

mName = name ;

mFingerprint = fingerprint ;

mTimeMs = timeMs ;

}

/** The name of this partition, e.g. "system", or "vendor" */

@NonNull

public String getName () {

return mName ;

}

/** The build fingerprint of this partition, see {@link Build#FINGERPRINT}. */

@NonNull

public String getFingerprint () {

return mFingerprint ;

}

/** The time (ms since epoch), at which this partition was built, see {@link Build#TIME}. */

public long getBuildTimeMillis () {

return mTimeMs ;

}

@Override

public boolean equals ( Object o ) {

if (!( o instanceof Partition )) {

return false ;

}

Partition op = ( Partition ) o ;

return mName . equals ( op . mName )

&& mFingerprint . equals ( op . mFingerprint )

&& mTimeMs == op . mTimeMs ;

}

@Override

public int hashCode () {

return Objects . hash ( mName , mFingerprint , mTimeMs );

}

}

/**

* Get build information about partitions that have a separate fingerprint defined.

*

* The list includes partitions that are suitable candidates for over-the-air updates. This is

* not an exhaustive list of partitions on the device.

*/

@NonNull

public static List < Partition > getFingerprintedPartitions () {

ArrayList < Partition > partitions = new ArrayList ();

String [] names = new String [] {

"bootimage" , "odm" , "product" , "system_ext" , Partition . PARTITION_NAME_SYSTEM ,

"vendor"

};

for ( String name : names ) {

String fingerprint = SystemProperties . get ( "ro." + name + ".build.fingerprint" );

if ( TextUtils . isEmpty ( fingerprint )) {

continue ;

}

long time = getLong ( "ro." + name + ".build.date.utc" ) * 1000 ;

partitions . add ( new Partition ( name , fingerprint , time ));

}

return partitions ;

}

// The following properties only make sense for internal engineering builds.

/** The time at which the build was produced, given in milliseconds since the UNIX epoch. */

public static final long TIME = getLong ( "ro.build.date.utc" ) * 1000 ;

public static final String USER = getString ( "ro.build.user" );

public static final String HOST = getString ( "ro.build.host" );

/**

* Returns true if we are running a debug build such as "user-debug" or "eng".

* @hide

*/

@UnsupportedAppUsage

public static final boolean IS_DEBUGGABLE =

SystemProperties . getInt ( "ro.debuggable" , 0 ) == 1 ;

/** {@hide} */

public static final boolean IS_ENG = "eng" . equals ( TYPE );

/** {@hide} */

public static final boolean IS_USERDEBUG = "userdebug" . equals ( TYPE );

/** {@hide} */

public static final boolean IS_USER = "user" . equals ( TYPE );

/**

* Whether this build is running inside a container.

*

* We should try to avoid checking this flag if possible to minimize

* unnecessarily diverging from non-container Android behavior.

* Checking this flag is acceptable when low-level resources being

* different, e.g. the availability of certain capabilities, access to

* system resources being restricted, and the fact that the host OS might

* handle some features for us.

* For higher-level behavior differences, other checks should be preferred.

* @hide

*/

public static final boolean IS_CONTAINER =

SystemProperties . getBoolean ( "ro.boot.container" , false );

/**

* Specifies whether the permissions needed by a legacy app should be

* reviewed before any of its components can run. A legacy app is one

* with targetSdkVersion < 23, i.e apps using the old permission model.

* If review is not required, permissions are reviewed before the app

* is installed.

*

* @hide

* @removed

*/

@SystemApi

public static final boolean PERMISSIONS_REVIEW_REQUIRED = true ;

/**

* Returns the version string for the radio firmware. May return

* null (if, for instance, the radio is not currently on).

*/

public static String getRadioVersion () {

return joinListOrElse ( TelephonyProperties . baseband_version (), null );

}

@UnsupportedAppUsage

private static String getString ( String property ) {

return SystemProperties . get ( property , UNKNOWN );

}

private static String [] getStringList ( String property , String separator ) {

String value = SystemProperties . get ( property );

if ( value . isEmpty ()) {

return new String [ 0 ];

} else {

return value . split ( separator );

}

}

@UnsupportedAppUsage

private static long getLong ( String property ) {

try {

return Long . parseLong ( SystemProperties . get ( property ));

} catch ( NumberFormatException e ) {

return - 1 ;

}

}

private static < T > String joinListOrElse ( List < T > list , String defaultValue ) {

String ret = list . stream (). map ( elem -> elem == null ? "" : elem . toString ())

. collect ( Collectors . joining ( "," ));

return ret . isEmpty () ? defaultValue : ret ;

}