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      1 /*
      2  * Copyright (C) 2007 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.os;
     18 
     19 import android.text.TextUtils;
     20 import android.util.Slog;
     21 
     22 import com.android.internal.telephony.TelephonyProperties;
     23 
     24 import dalvik.system.VMRuntime;
     25 
     26 import java.util.Objects;
     27 
     28 /**
     29  * Information about the current build, extracted from system properties.
     30  */
     31 public class Build {
     32     private static final String TAG = "Build";
     33 
     34     /** Value used for when a build property is unknown. */
     35     public static final String UNKNOWN = "unknown";
     36 
     37     /** Either a changelist number, or a label like "M4-rc20". */
     38     public static final String ID = getString("ro.build.id");
     39 
     40     /** A build ID string meant for displaying to the user */
     41     public static final String DISPLAY = getString("ro.build.display.id");
     42 
     43     /** The name of the overall product. */
     44     public static final String PRODUCT = getString("ro.product.name");
     45 
     46     /** The name of the industrial design. */
     47     public static final String DEVICE = getString("ro.product.device");
     48 
     49     /** The name of the underlying board, like "goldfish". */
     50     public static final String BOARD = getString("ro.product.board");
     51 
     52     /**
     53      * The name of the instruction set (CPU type + ABI convention) of native code.
     54      *
     55      * @deprecated Use {@link #SUPPORTED_ABIS} instead.
     56      */
     57     @Deprecated
     58     public static final String CPU_ABI;
     59 
     60     /**
     61      * The name of the second instruction set (CPU type + ABI convention) of native code.
     62      *
     63      * @deprecated Use {@link #SUPPORTED_ABIS} instead.
     64      */
     65     @Deprecated
     66     public static final String CPU_ABI2;
     67 
     68     /** The manufacturer of the product/hardware. */
     69     public static final String MANUFACTURER = getString("ro.product.manufacturer");
     70 
     71     /** The consumer-visible brand with which the product/hardware will be associated, if any. */
     72     public static final String BRAND = getString("ro.product.brand");
     73 
     74     /** The end-user-visible name for the end product. */
     75     public static final String MODEL = getString("ro.product.model");
     76 
     77     /** The system bootloader version number. */
     78     public static final String BOOTLOADER = getString("ro.bootloader");
     79 
     80     /**
     81      * The radio firmware version number.
     82      *
     83      * @deprecated The radio firmware version is frequently not
     84      * available when this class is initialized, leading to a blank or
     85      * "unknown" value for this string.  Use
     86      * {@link #getRadioVersion} instead.
     87      */
     88     @Deprecated
     89     public static final String RADIO = getString(TelephonyProperties.PROPERTY_BASEBAND_VERSION);
     90 
     91     /** The name of the hardware (from the kernel command line or /proc). */
     92     public static final String HARDWARE = getString("ro.hardware");
     93 
     94     /** A hardware serial number, if available.  Alphanumeric only, case-insensitive. */
     95     public static final String SERIAL = getString("ro.serialno");
     96 
     97     /**
     98      * An ordered list of ABIs supported by this device. The most preferred ABI is the first
     99      * element in the list.
    100      *
    101      * See {@link #SUPPORTED_32_BIT_ABIS} and {@link #SUPPORTED_64_BIT_ABIS}.
    102      */
    103     public static final String[] SUPPORTED_ABIS = getStringList("ro.product.cpu.abilist", ",");
    104 
    105     /**
    106      * An ordered list of <b>32 bit</b> ABIs supported by this device. The most preferred ABI
    107      * is the first element in the list.
    108      *
    109      * See {@link #SUPPORTED_ABIS} and {@link #SUPPORTED_64_BIT_ABIS}.
    110      */
    111     public static final String[] SUPPORTED_32_BIT_ABIS =
    112             getStringList("ro.product.cpu.abilist32", ",");
    113 
    114     /**
    115      * An ordered list of <b>64 bit</b> ABIs supported by this device. The most preferred ABI
    116      * is the first element in the list.
    117      *
    118      * See {@link #SUPPORTED_ABIS} and {@link #SUPPORTED_32_BIT_ABIS}.
    119      */
    120     public static final String[] SUPPORTED_64_BIT_ABIS =
    121             getStringList("ro.product.cpu.abilist64", ",");
    122 
    123 
    124     static {
    125         /*
    126          * Adjusts CPU_ABI and CPU_ABI2 depending on whether or not a given process is 64 bit.
    127          * 32 bit processes will always see 32 bit ABIs in these fields for backward
    128          * compatibility.
    129          */
    130         final String[] abiList;
    131         if (VMRuntime.getRuntime().is64Bit()) {
    132             abiList = SUPPORTED_64_BIT_ABIS;
    133         } else {
    134             abiList = SUPPORTED_32_BIT_ABIS;
    135         }
    136 
    137         CPU_ABI = abiList[0];
    138         if (abiList.length > 1) {
    139             CPU_ABI2 = abiList[1];
    140         } else {
    141             CPU_ABI2 = "";
    142         }
    143     }
    144 
    145     /** Various version strings. */
    146     public static class VERSION {
    147         /**
    148          * The internal value used by the underlying source control to
    149          * represent this build.  E.g., a perforce changelist number
    150          * or a git hash.
    151          */
    152         public static final String INCREMENTAL = getString("ro.build.version.incremental");
    153 
    154         /**
    155          * The user-visible version string.  E.g., "1.0" or "3.4b5".
    156          */
    157         public static final String RELEASE = getString("ro.build.version.release");
    158 
    159         /**
    160          * The user-visible SDK version of the framework in its raw String
    161          * representation; use {@link #SDK_INT} instead.
    162          *
    163          * @deprecated Use {@link #SDK_INT} to easily get this as an integer.
    164          */
    165         @Deprecated
    166         public static final String SDK = getString("ro.build.version.sdk");
    167 
    168         /**
    169          * The user-visible SDK version of the framework; its possible
    170          * values are defined in {@link Build.VERSION_CODES}.
    171          */
    172         public static final int SDK_INT = SystemProperties.getInt(
    173                 "ro.build.version.sdk", 0);
    174 
    175         /**
    176          * The current development codename, or the string "REL" if this is
    177          * a release build.
    178          */
    179         public static final String CODENAME = getString("ro.build.version.codename");
    180 
    181         private static final String[] ALL_CODENAMES
    182                 = getStringList("ro.build.version.all_codenames", ",");
    183 
    184         /**
    185          * @hide
    186          */
    187         public static final String[] ACTIVE_CODENAMES = "REL".equals(ALL_CODENAMES[0])
    188                 ? new String[0] : ALL_CODENAMES;
    189 
    190         /**
    191          * The SDK version to use when accessing resources.
    192          * Use the current SDK version code.  For every active development codename
    193          * we are operating under, we bump the assumed resource platform version by 1.
    194          * @hide
    195          */
    196         public static final int RESOURCES_SDK_INT = SDK_INT + ACTIVE_CODENAMES.length;
    197     }
    198 
    199     /**
    200      * Enumeration of the currently known SDK version codes.  These are the
    201      * values that can be found in {@link VERSION#SDK}.  Version numbers
    202      * increment monotonically with each official platform release.
    203      */
    204     public static class VERSION_CODES {
    205         /**
    206          * Magic version number for a current development build, which has
    207          * not yet turned into an official release.
    208          */
    209         public static final int CUR_DEVELOPMENT = 10000;
    210 
    211         /**
    212          * October 2008: The original, first, version of Android.  Yay!
    213          */
    214         public static final int BASE = 1;
    215 
    216         /**
    217          * February 2009: First Android update, officially called 1.1.
    218          */
    219         public static final int BASE_1_1 = 2;
    220 
    221         /**
    222          * May 2009: Android 1.5.
    223          */
    224         public static final int CUPCAKE = 3;
    225 
    226         /**
    227          * September 2009: Android 1.6.
    228          *
    229          * <p>Applications targeting this or a later release will get these
    230          * new changes in behavior:</p>
    231          * <ul>
    232          * <li> They must explicitly request the
    233          * {@link android.Manifest.permission#WRITE_EXTERNAL_STORAGE} permission to be
    234          * able to modify the contents of the SD card.  (Apps targeting
    235          * earlier versions will always request the permission.)
    236          * <li> They must explicitly request the
    237          * {@link android.Manifest.permission#READ_PHONE_STATE} permission to be
    238          * able to be able to retrieve phone state info.  (Apps targeting
    239          * earlier versions will always request the permission.)
    240          * <li> They are assumed to support different screen densities and
    241          * sizes.  (Apps targeting earlier versions are assumed to only support
    242          * medium density normal size screens unless otherwise indicated).
    243          * They can still explicitly specify screen support either way with the
    244          * supports-screens manifest tag.
    245          * <li> {@link android.widget.TabHost} will use the new dark tab
    246          * background design.
    247          * </ul>
    248          */
    249         public static final int DONUT = 4;
    250 
    251         /**
    252          * November 2009: Android 2.0
    253          *
    254          * <p>Applications targeting this or a later release will get these
    255          * new changes in behavior:</p>
    256          * <ul>
    257          * <li> The {@link android.app.Service#onStartCommand
    258          * Service.onStartCommand} function will return the new
    259          * {@link android.app.Service#START_STICKY} behavior instead of the
    260          * old compatibility {@link android.app.Service#START_STICKY_COMPATIBILITY}.
    261          * <li> The {@link android.app.Activity} class will now execute back
    262          * key presses on the key up instead of key down, to be able to detect
    263          * canceled presses from virtual keys.
    264          * <li> The {@link android.widget.TabWidget} class will use a new color scheme
    265          * for tabs. In the new scheme, the foreground tab has a medium gray background
    266          * the background tabs have a dark gray background.
    267          * </ul>
    268          */
    269         public static final int ECLAIR = 5;
    270 
    271         /**
    272          * December 2009: Android 2.0.1
    273          */
    274         public static final int ECLAIR_0_1 = 6;
    275 
    276         /**
    277          * January 2010: Android 2.1
    278          */
    279         public static final int ECLAIR_MR1 = 7;
    280 
    281         /**
    282          * June 2010: Android 2.2
    283          */
    284         public static final int FROYO = 8;
    285 
    286         /**
    287          * November 2010: Android 2.3
    288          *
    289          * <p>Applications targeting this or a later release will get these
    290          * new changes in behavior:</p>
    291          * <ul>
    292          * <li> The application's notification icons will be shown on the new
    293          * dark status bar background, so must be visible in this situation.
    294          * </ul>
    295          */
    296         public static final int GINGERBREAD = 9;
    297 
    298         /**
    299          * February 2011: Android 2.3.3.
    300          */
    301         public static final int GINGERBREAD_MR1 = 10;
    302 
    303         /**
    304          * February 2011: Android 3.0.
    305          *
    306          * <p>Applications targeting this or a later release will get these
    307          * new changes in behavior:</p>
    308          * <ul>
    309          * <li> The default theme for applications is now dark holographic:
    310          *      {@link android.R.style#Theme_Holo}.
    311          * <li> On large screen devices that do not have a physical menu
    312          * button, the soft (compatibility) menu is disabled.
    313          * <li> The activity lifecycle has changed slightly as per
    314          * {@link android.app.Activity}.
    315          * <li> An application will crash if it does not call through
    316          * to the super implementation of its
    317          * {@link android.app.Activity#onPause Activity.onPause()} method.
    318          * <li> When an application requires a permission to access one of
    319          * its components (activity, receiver, service, provider), this
    320          * permission is no longer enforced when the application wants to
    321          * access its own component.  This means it can require a permission
    322          * on a component that it does not itself hold and still access that
    323          * component.
    324          * <li> {@link android.content.Context#getSharedPreferences
    325          * Context.getSharedPreferences()} will not automatically reload
    326          * the preferences if they have changed on storage, unless
    327          * {@link android.content.Context#MODE_MULTI_PROCESS} is used.
    328          * <li> {@link android.view.ViewGroup#setMotionEventSplittingEnabled}
    329          * will default to true.
    330          * <li> {@link android.view.WindowManager.LayoutParams#FLAG_SPLIT_TOUCH}
    331          * is enabled by default on windows.
    332          * <li> {@link android.widget.PopupWindow#isSplitTouchEnabled()
    333          * PopupWindow.isSplitTouchEnabled()} will return true by default.
    334          * <li> {@link android.widget.GridView} and {@link android.widget.ListView}
    335          * will use {@link android.view.View#setActivated View.setActivated}
    336          * for selected items if they do not implement {@link android.widget.Checkable}.
    337          * <li> {@link android.widget.Scroller} will be constructed with
    338          * "flywheel" behavior enabled by default.
    339          * </ul>
    340          */
    341         public static final int HONEYCOMB = 11;
    342 
    343         /**
    344          * May 2011: Android 3.1.
    345          */
    346         public static final int HONEYCOMB_MR1 = 12;
    347 
    348         /**
    349          * June 2011: Android 3.2.
    350          *
    351          * <p>Update to Honeycomb MR1 to support 7 inch tablets, improve
    352          * screen compatibility mode, etc.</p>
    353          *
    354          * <p>As of this version, applications that don't say whether they
    355          * support XLARGE screens will be assumed to do so only if they target
    356          * {@link #HONEYCOMB} or later; it had been {@link #GINGERBREAD} or
    357          * later.  Applications that don't support a screen size at least as
    358          * large as the current screen will provide the user with a UI to
    359          * switch them in to screen size compatibility mode.</p>
    360          *
    361          * <p>This version introduces new screen size resource qualifiers
    362          * based on the screen size in dp: see
    363          * {@link android.content.res.Configuration#screenWidthDp},
    364          * {@link android.content.res.Configuration#screenHeightDp}, and
    365          * {@link android.content.res.Configuration#smallestScreenWidthDp}.
    366          * Supplying these in &lt;supports-screens&gt; as per
    367          * {@link android.content.pm.ApplicationInfo#requiresSmallestWidthDp},
    368          * {@link android.content.pm.ApplicationInfo#compatibleWidthLimitDp}, and
    369          * {@link android.content.pm.ApplicationInfo#largestWidthLimitDp} is
    370          * preferred over the older screen size buckets and for older devices
    371          * the appropriate buckets will be inferred from them.</p>
    372          *
    373          * <p>Applications targeting this or a later release will get these
    374          * new changes in behavior:</p>
    375          * <ul>
    376          * <li><p>New {@link android.content.pm.PackageManager#FEATURE_SCREEN_PORTRAIT}
    377          * and {@link android.content.pm.PackageManager#FEATURE_SCREEN_LANDSCAPE}
    378          * features were introduced in this release.  Applications that target
    379          * previous platform versions are assumed to require both portrait and
    380          * landscape support in the device; when targeting Honeycomb MR1 or
    381          * greater the application is responsible for specifying any specific
    382          * orientation it requires.</p>
    383          * <li><p>{@link android.os.AsyncTask} will use the serial executor
    384          * by default when calling {@link android.os.AsyncTask#execute}.</p>
    385          * <li><p>{@link android.content.pm.ActivityInfo#configChanges
    386          * ActivityInfo.configChanges} will have the
    387          * {@link android.content.pm.ActivityInfo#CONFIG_SCREEN_SIZE} and
    388          * {@link android.content.pm.ActivityInfo#CONFIG_SMALLEST_SCREEN_SIZE}
    389          * bits set; these need to be cleared for older applications because
    390          * some developers have done absolute comparisons against this value
    391          * instead of correctly masking the bits they are interested in.
    392          * </ul>
    393          */
    394         public static final int HONEYCOMB_MR2 = 13;
    395 
    396         /**
    397          * October 2011: Android 4.0.
    398          *
    399          * <p>Applications targeting this or a later release will get these
    400          * new changes in behavior:</p>
    401          * <ul>
    402          * <li> For devices without a dedicated menu key, the software compatibility
    403          * menu key will not be shown even on phones.  By targeting Ice Cream Sandwich
    404          * or later, your UI must always have its own menu UI affordance if needed,
    405          * on both tablets and phones.  The ActionBar will take care of this for you.
    406          * <li> 2d drawing hardware acceleration is now turned on by default.
    407          * You can use
    408          * {@link android.R.attr#hardwareAccelerated android:hardwareAccelerated}
    409          * to turn it off if needed, although this is strongly discouraged since
    410          * it will result in poor performance on larger screen devices.
    411          * <li> The default theme for applications is now the "device default" theme:
    412          *      {@link android.R.style#Theme_DeviceDefault}. This may be the
    413          *      holo dark theme or a different dark theme defined by the specific device.
    414          *      The {@link android.R.style#Theme_Holo} family must not be modified
    415          *      for a device to be considered compatible. Applications that explicitly
    416          *      request a theme from the Holo family will be guaranteed that these themes
    417          *      will not change character within the same platform version. Applications
    418          *      that wish to blend in with the device should use a theme from the
    419          *      {@link android.R.style#Theme_DeviceDefault} family.
    420          * <li> Managed cursors can now throw an exception if you directly close
    421          * the cursor yourself without stopping the management of it; previously failures
    422          * would be silently ignored.
    423          * <li> The fadingEdge attribute on views will be ignored (fading edges is no
    424          * longer a standard part of the UI).  A new requiresFadingEdge attribute allows
    425          * applications to still force fading edges on for special cases.
    426          * <li> {@link android.content.Context#bindService Context.bindService()}
    427          * will not automatically add in {@link android.content.Context#BIND_WAIVE_PRIORITY}.
    428          * <li> App Widgets will have standard padding automatically added around
    429          * them, rather than relying on the padding being baked into the widget itself.
    430          * <li> An exception will be thrown if you try to change the type of a
    431          * window after it has been added to the window manager.  Previously this
    432          * would result in random incorrect behavior.
    433          * <li> {@link android.view.animation.AnimationSet} will parse out
    434          * the duration, fillBefore, fillAfter, repeatMode, and startOffset
    435          * XML attributes that are defined.
    436          * <li> {@link android.app.ActionBar#setHomeButtonEnabled
    437          * ActionBar.setHomeButtonEnabled()} is false by default.
    438          * </ul>
    439          */
    440         public static final int ICE_CREAM_SANDWICH = 14;
    441 
    442         /**
    443          * December 2011: Android 4.0.3.
    444          */
    445         public static final int ICE_CREAM_SANDWICH_MR1 = 15;
    446 
    447         /**
    448          * June 2012: Android 4.1.
    449          *
    450          * <p>Applications targeting this or a later release will get these
    451          * new changes in behavior:</p>
    452          * <ul>
    453          * <li> You must explicitly request the {@link android.Manifest.permission#READ_CALL_LOG}
    454          * and/or {@link android.Manifest.permission#WRITE_CALL_LOG} permissions;
    455          * access to the call log is no longer implicitly provided through
    456          * {@link android.Manifest.permission#READ_CONTACTS} and
    457          * {@link android.Manifest.permission#WRITE_CONTACTS}.
    458          * <li> {@link android.widget.RemoteViews} will throw an exception if
    459          * setting an onClick handler for views being generated by a
    460          * {@link android.widget.RemoteViewsService} for a collection container;
    461          * previously this just resulted in a warning log message.
    462          * <li> New {@link android.app.ActionBar} policy for embedded tabs:
    463          * embedded tabs are now always stacked in the action bar when in portrait
    464          * mode, regardless of the size of the screen.
    465          * <li> {@link android.webkit.WebSettings#setAllowFileAccessFromFileURLs(boolean)
    466          * WebSettings.setAllowFileAccessFromFileURLs} and
    467          * {@link android.webkit.WebSettings#setAllowUniversalAccessFromFileURLs(boolean)
    468          * WebSettings.setAllowUniversalAccessFromFileURLs} default to false.
    469          * <li> Calls to {@link android.content.pm.PackageManager#setComponentEnabledSetting
    470          * PackageManager.setComponentEnabledSetting} will now throw an
    471          * IllegalArgumentException if the given component class name does not
    472          * exist in the application's manifest.
    473          * <li> {@link android.nfc.NfcAdapter#setNdefPushMessage
    474          * NfcAdapter.setNdefPushMessage},
    475          * {@link android.nfc.NfcAdapter#setNdefPushMessageCallback
    476          * NfcAdapter.setNdefPushMessageCallback} and
    477          * {@link android.nfc.NfcAdapter#setOnNdefPushCompleteCallback
    478          * NfcAdapter.setOnNdefPushCompleteCallback} will throw
    479          * IllegalStateException if called after the Activity has been destroyed.
    480          * <li> Accessibility services must require the new
    481          * {@link android.Manifest.permission#BIND_ACCESSIBILITY_SERVICE} permission or
    482          * they will not be available for use.
    483          * <li> {@link android.accessibilityservice.AccessibilityServiceInfo#FLAG_INCLUDE_NOT_IMPORTANT_VIEWS
    484          * AccessibilityServiceInfo.FLAG_INCLUDE_NOT_IMPORTANT_VIEWS} must be set
    485          * for unimportant views to be included in queries.
    486          * </ul>
    487          */
    488         public static final int JELLY_BEAN = 16;
    489 
    490         /**
    491          * November 2012: Android 4.2, Moar jelly beans!
    492          *
    493          * <p>Applications targeting this or a later release will get these
    494          * new changes in behavior:</p>
    495          * <ul>
    496          * <li>Content Providers: The default value of {@code android:exported} is now
    497          * {@code false}. See
    498          * <a href="{@docRoot}guide/topics/manifest/provider-element.html#exported">
    499          * the android:exported section</a> in the provider documentation for more details.</li>
    500          * <li>{@link android.view.View#getLayoutDirection() View.getLayoutDirection()}
    501          * can return different values than {@link android.view.View#LAYOUT_DIRECTION_LTR}
    502          * based on the locale etc.
    503          * <li> {@link android.webkit.WebView#addJavascriptInterface(Object, String)
    504          * WebView.addJavascriptInterface} requires explicit annotations on methods
    505          * for them to be accessible from Javascript.
    506          * </ul>
    507          */
    508         public static final int JELLY_BEAN_MR1 = 17;
    509 
    510         /**
    511          * July 2013: Android 4.3, the revenge of the beans.
    512          */
    513         public static final int JELLY_BEAN_MR2 = 18;
    514 
    515         /**
    516          * October 2013: Android 4.4, KitKat, another tasty treat.
    517          *
    518          * <p>Applications targeting this or a later release will get these
    519          * new changes in behavior:</p>
    520          * <ul>
    521          * <li> The default result of {android.preference.PreferenceActivity#isValidFragment
    522          * PreferenceActivity.isValueFragment} becomes false instead of true.</li>
    523          * <li> In {@link android.webkit.WebView}, apps targeting earlier versions will have
    524          * JS URLs evaluated directly and any result of the evaluation will not replace
    525          * the current page content.  Apps targetting KITKAT or later that load a JS URL will
    526          * have the result of that URL replace the content of the current page</li>
    527          * <li> {@link android.app.AlarmManager#set AlarmManager.set} becomes interpreted as
    528          * an inexact value, to give the system more flexibility in scheduling alarms.</li>
    529          * <li> {@link android.content.Context#getSharedPreferences(String, int)
    530          * Context.getSharedPreferences} no longer allows a null name.</li>
    531          * <li> {@link android.widget.RelativeLayout} changes to compute wrapped content
    532          * margins correctly.</li>
    533          * <li> {@link android.app.ActionBar}'s window content overlay is allowed to be
    534          * drawn.</li>
    535          * <li>The {@link android.Manifest.permission#READ_EXTERNAL_STORAGE}
    536          * permission is now always enforced.</li>
    537          * <li>Access to package-specific external storage directories belonging
    538          * to the calling app no longer requires the
    539          * {@link android.Manifest.permission#READ_EXTERNAL_STORAGE} or
    540          * {@link android.Manifest.permission#WRITE_EXTERNAL_STORAGE}
    541          * permissions.</li>
    542          * </ul>
    543          */
    544         public static final int KITKAT = 19;
    545 
    546         /**
    547          * Android 4.4W: KitKat for watches, snacks on the run.
    548          *
    549          * <p>Applications targeting this or a later release will get these
    550          * new changes in behavior:</p>
    551          * <ul>
    552          * <li>{@link android.app.AlertDialog} might not have a default background if the theme does
    553          * not specify one.</li>
    554          * </ul>
    555          */
    556         public static final int KITKAT_WATCH = 20;
    557 
    558         /**
    559          * Temporary until we completely switch to {@link #LOLLIPOP}.
    560          * @hide
    561          */
    562         public static final int L = 21;
    563 
    564         /**
    565          * Lollipop.  A flat one with beautiful shadows.  But still tasty.
    566          *
    567          * <p>Applications targeting this or a later release will get these
    568          * new changes in behavior:</p>
    569          * <ul>
    570          * <li> {@link android.content.Context#bindService Context.bindService} now
    571          * requires an explicit Intent, and will throw an exception if given an implicit
    572          * Intent.</li>
    573          * <li> {@link android.app.Notification.Builder Notification.Builder} will
    574          * not have the colors of their various notification elements adjusted to better
    575          * match the new material design look.</li>
    576          * <li> {@link android.os.Message} will validate that a message is not currently
    577          * in use when it is recycled.</li>
    578          * <li> Hardware accelerated drawing in windows will be enabled automatically
    579          * in most places.</li>
    580          * <li> {@link android.widget.Spinner} throws an exception if attaching an
    581          * adapter with more than one item type.</li>
    582          * <li> If the app is a launcher, the launcher will be available to the user
    583          * even when they are using corporate profiles (which requires that the app
    584          * use {@link android.content.pm.LauncherApps} to correctly populate its
    585          * apps UI).</li>
    586          * <li> Calling {@link android.app.Service#stopForeground Service.stopForeground}
    587          * with removeNotification false will modify the still posted notification so that
    588          * it is no longer forced to be ongoing.</li>
    589          * <li> A {@link android.service.dreams.DreamService} must require the
    590          * {@link android.Manifest.permission#BIND_DREAM_SERVICE} permission to be usable.</li>
    591          * </ul>
    592          */
    593         public static final int LOLLIPOP = 21;
    594 
    595         /**
    596          * Lollipop with an extra sugar coating on the outside!
    597          */
    598         public static final int LOLLIPOP_MR1 = 22;
    599     }
    600 
    601     /** The type of build, like "user" or "eng". */
    602     public static final String TYPE = getString("ro.build.type");
    603 
    604     /** Comma-separated tags describing the build, like "unsigned,debug". */
    605     public static final String TAGS = getString("ro.build.tags");
    606 
    607     /** A string that uniquely identifies this build.  Do not attempt to parse this value. */
    608     public static final String FINGERPRINT = deriveFingerprint();
    609 
    610     /**
    611      * Some devices split the fingerprint components between multiple
    612      * partitions, so we might derive the fingerprint at runtime.
    613      */
    614     private static String deriveFingerprint() {
    615         String finger = SystemProperties.get("ro.build.fingerprint");
    616         if (TextUtils.isEmpty(finger)) {
    617             finger = getString("ro.product.brand") + '/' +
    618                     getString("ro.product.name") + '/' +
    619                     getString("ro.product.device") + ':' +
    620                     getString("ro.build.version.release") + '/' +
    621                     getString("ro.build.id") + '/' +
    622                     getString("ro.build.version.incremental") + ':' +
    623                     getString("ro.build.type") + '/' +
    624                     getString("ro.build.tags");
    625         }
    626         return finger;
    627     }
    628 
    629     /**
    630      * Ensure that raw fingerprint system property is defined. If it was derived
    631      * dynamically by {@link #deriveFingerprint()} this is where we push the
    632      * derived value into the property service.
    633      *
    634      * @hide
    635      */
    636     public static void ensureFingerprintProperty() {
    637         if (TextUtils.isEmpty(SystemProperties.get("ro.build.fingerprint"))) {
    638             try {
    639                 SystemProperties.set("ro.build.fingerprint", FINGERPRINT);
    640             } catch (IllegalArgumentException e) {
    641                 Slog.e(TAG, "Failed to set fingerprint property", e);
    642             }
    643         }
    644     }
    645 
    646     /**
    647      * Check that device fingerprint is defined and that it matches across
    648      * various partitions.
    649      *
    650      * @hide
    651      */
    652     public static boolean isFingerprintConsistent() {
    653         final String system = SystemProperties.get("ro.build.fingerprint");
    654         final String vendor = SystemProperties.get("ro.vendor.build.fingerprint");
    655 
    656         if (TextUtils.isEmpty(system)) {
    657             Slog.e(TAG, "Required ro.build.fingerprint is empty!");
    658             return false;
    659         }
    660 
    661         if (!TextUtils.isEmpty(vendor)) {
    662             if (!Objects.equals(system, vendor)) {
    663                 Slog.e(TAG, "Mismatched fingerprints; system reported " + system
    664                         + " but vendor reported " + vendor);
    665                 return false;
    666             }
    667         }
    668 
    669         return true;
    670     }
    671 
    672     // The following properties only make sense for internal engineering builds.
    673     public static final long TIME = getLong("ro.build.date.utc") * 1000;
    674     public static final String USER = getString("ro.build.user");
    675     public static final String HOST = getString("ro.build.host");
    676 
    677     /**
    678      * Returns true if we are running a debug build such as "user-debug" or "eng".
    679      * @hide
    680      */
    681     public static final boolean IS_DEBUGGABLE =
    682             SystemProperties.getInt("ro.debuggable", 0) == 1;
    683 
    684     /**
    685      * Returns the version string for the radio firmware.  May return
    686      * null (if, for instance, the radio is not currently on).
    687      */
    688     public static String getRadioVersion() {
    689         return SystemProperties.get(TelephonyProperties.PROPERTY_BASEBAND_VERSION, null);
    690     }
    691 
    692     private static String getString(String property) {
    693         return SystemProperties.get(property, UNKNOWN);
    694     }
    695 
    696     private static String[] getStringList(String property, String separator) {
    697         String value = SystemProperties.get(property);
    698         if (value.isEmpty()) {
    699             return new String[0];
    700         } else {
    701             return value.split(separator);
    702         }
    703     }
    704 
    705     private static long getLong(String property) {
    706         try {
    707             return Long.parseLong(SystemProperties.get(property));
    708         } catch (NumberFormatException e) {
    709             return -1;
    710         }
    711     }
    712 }
    713