http://code.google.com/p/roottools/

如果你不想使用jar文件，请使用下面的代码:

public static boolean findBinary(String binaryName) {
        boolean found = false;
        if (!found) {
            String[] places = { "/sbin/", "/system/bin/", "/system/xbin/",
                    "/data/local/xbin/", "/data/local/bin/",
                    "/system/sd/xbin/", "/system/bin/failsafe/", "/data/local/" };
            for (String where : places) {
                if (new File(where + binaryName).exists()) {
                    found = true;

                    break;
                }
            }
        }
        return found;
    }

程序将尝试查找su文件夹:

private static boolean isRooted() {
        return findBinary("su");
    }

例子:

if (isRooted()) {
   textView.setText("Device Rooted");

} else {
   textView.setText("Device Unrooted");
}

另外两个方法，如果你想检查一个设备在你的应用程序中是否具有根功能:

检查是否存在“su”二进制文件:从Runtime.getRuntime().exec()运行"which su" 在/system/app/ SuperUser.apk目录下查找SuperUser.apk

    public static boolean isRootAvailable(){
            Process p = null;
            try{
               p = Runtime.getRuntime().exec(new String[] {"su"});
               writeCommandToConsole(p,"exit 0");
               int result = p.waitFor();
               if(result != 0)
                   throw new Exception("Root check result with exit command " + result);
               return true;
            } catch (IOException e) {
                Log.e(LOG_TAG, "Su executable is not available ", e);
            } catch (Exception e) {
                Log.e(LOG_TAG, "Root is unavailable ", e);
            }finally {
                if(p != null)
                    p.destroy();
            }
            return false;
        }
 private static String writeCommandToConsole(Process proc, String command, boolean ignoreError) throws Exception{
            byte[] tmpArray = new byte[1024];
            proc.getOutputStream().write((command + "\n").getBytes());
            proc.getOutputStream().flush();
            int bytesRead = 0;
            if(proc.getErrorStream().available() > 0){
                if((bytesRead = proc.getErrorStream().read(tmpArray)) > 1){
                    Log.e(LOG_TAG,new String(tmpArray,0,bytesRead));
                    if(!ignoreError)
                        throw new Exception(new String(tmpArray,0,bytesRead));
                }
            }
            if(proc.getInputStream().available() > 0){
                bytesRead = proc.getInputStream().read(tmpArray);
                Log.i(LOG_TAG, new String(tmpArray,0,bytesRead));
            }
            return new String(tmpArray);
        }

一些用于设置系统属性ro的修改版本。Modversion用于此目的。事情似乎已经发生了变化;我几个月前在TheDude上的构建是这样的:

cmb@apollo:~$ adb -d shell getprop |grep build
[ro.build.id]: [CUPCAKE]
[ro.build.display.id]: [htc_dream-eng 1.5 CUPCAKE eng.TheDudeAbides.20090427.235325 test-keys]
[ro.build.version.incremental]: [eng.TheDude.2009027.235325]
[ro.build.version.sdk]: [3]
[ro.build.version.release]: [1.5]
[ro.build.date]: [Mon Apr 20 01:42:32 CDT 2009]
[ro.build.date.utc]: [1240209752]
[ro.build.type]: [eng]
[ro.build.user]: [TheDude]
[ro.build.host]: [ender]
[ro.build.tags]: [test-keys]
[ro.build.product]: [dream]
[ro.build.description]: [kila-user 1.1 PLAT-RC33 126986 ota-rel-keys,release-keys]
[ro.build.fingerprint]: [tmobile/kila/dream/trout:1.1/PLAT-RC33/126986:user/ota-rel-keys,release-keys]
[ro.build.changelist]: [17615# end build properties]

另一方面，来自1.5 SDK的模拟器，运行1.5镜像，也有根，可能类似于Android Dev Phone 1(你可能想要允许)，并有这个:

cmb@apollo:~$ adb -e shell getprop |grep build
[ro.build.id]: [CUPCAKE]
[ro.build.display.id]: [sdk-eng 1.5 CUPCAKE 148875 test-keys]
[ro.build.version.incremental]: [148875]
[ro.build.version.sdk]: [3]
[ro.build.version.release]: [1.5]
[ro.build.date]: [Thu May 14 18:09:10 PDT 2009]
[ro.build.date.utc]: [1242349750]
[ro.build.type]: [eng]
[ro.build.user]: [android-build]
[ro.build.host]: [undroid16.mtv.corp.google.com]
[ro.build.tags]: [test-keys]
[ro.build.product]: [generic]
[ro.build.description]: [sdk-eng 1.5 CUPCAKE 148875 test-keys]
[ro.build.fingerprint]: [generic/sdk/generic/:1.5/CUPCAKE/148875:eng/test-keys]

至于零售构建，我手头没有，但在site:xda developers.com下的各种搜索提供了大量信息。这是荷兰的G1, ro。build。tags没有test-key，我认为这可能是最可靠的属性。

根据这里的一些答案，我合并了它们，并添加了一个检查是否安装了一些已知的根管理器应用程序:

fun isProbablyRooted(context: Context, alsoIncludeCheckingRootManagerApp: Boolean = false): Boolean {
    return hasRootManagerSystemApp(context) || (alsoIncludeCheckingRootManagerApp && hasRootManagerSystemApp(context))
}

fun hasRootManagerSystemApp(context: Context): Boolean {
    val rootAppsPackageNames = arrayOf("com.topjohnwu.magisk", "eu.chainfire.supersu", "com.koushikdutta.superuser", "com.noshufou.android.su", "me.phh.superuser")
    rootAppsPackageNames.forEach { rootAppPackageName ->
        try {
            context.packageManager.getApplicationInfo(rootAppPackageName, 0)
            return true
        } catch (e: Exception) {
        }
    }
    return false
}

fun hasSuBinary(): Boolean {
    return try {
        findBinary("su")
    } catch (e: Exception) {
        e.printStackTrace()
        false
    }
}

private fun findBinary(binaryName: String): Boolean {
    val paths = System.getenv("PATH")
    if (!paths.isNullOrBlank()) {
        val systemPlaces: List<String> = paths.split(":")
        return systemPlaces.firstOrNull { File(it, binaryName).exists() } != null
    }
    val places = arrayOf("/sbin/", "/system/bin/", "/system/xbin/", "/data/local/xbin/", "/data/local/bin/",
            "/system/sd/xbin/", "/system/bin/failsafe/", "/data/local/")
    return places.firstOrNull { File(it, binaryName).exists() } != null
}

清单:

<queries>
    <package android:name="com.topjohnwu.magisk" />
    <package android:name="eu.chainfire.supersu" />
    <package android:name="com.koushikdutta.superuser" />
    <package android:name="com.noshufou.android.su" />
    <package android:name="me.phh.superuser" />
</queries>

当然，这仍然是一个猜测，就像所有其他解一样。 例如，用户可以安装Magisk，而无需对设备进行root操作。

这里列出的许多答案都有内在的问题:

Checking for test-keys is correlated with root access but doesn't necessarily guarantee it "PATH" directories should be derived from the actual "PATH" environment variable instead of being hard coded The existence of the "su" executable doesn't necessarily mean the device has been rooted The "which" executable may or may not be installed, and you should let the system resolve its path if possible Just because the SuperUser app is installed on the device does not mean the device has root access yet

Stericson的RootTools库似乎可以更合理地检查root。它还有很多额外的工具和实用程序，所以我强烈推荐它。然而，并没有解释它是如何专门检查根目录的，而且它可能比大多数应用程序真正需要的要重一些。

我已经创建了几个基于RootTools库的实用程序方法。如果你只是想检查“su”可执行文件是否在设备上，你可以使用以下方法:

public static boolean isRootAvailable(){
    for(String pathDir : System.getenv("PATH").split(":")){
        if(new File(pathDir, "su").exists()) {
            return true;
        }
    }
    return false;
}

这个方法简单地遍历“PATH”环境变量中列出的目录，并检查其中是否存在“su”文件。

为了真正检查root访问权限，必须实际运行“su”命令。如果安装了一个像SuperUser这样的应用程序，那么在这一点上它可能会要求root访问，或者如果它已经被授予/拒绝，吐司可能会显示是否授予/拒绝访问。一个很好的命令是“id”，这样您可以验证用户id实际上是0(根)。

下面是一个示例方法来确定是否授予了根访问权:

public static boolean isRootGiven(){
    if (isRootAvailable()) {
        Process process = null;
        try {
            process = Runtime.getRuntime().exec(new String[]{"su", "-c", "id"});
            BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
            String output = in.readLine();
            if (output != null && output.toLowerCase().contains("uid=0"))
                return true;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (process != null)
                process.destroy();
        }
    }

    return false;
}

实际测试运行"su"命令是很重要的，因为一些模拟器已经预安装了"su"可执行文件，但只允许某些用户像adb shell一样访问它。

在尝试运行“su”可执行文件之前检查它的存在也是很重要的，因为android已经知道不会正确地处理试图运行缺失命令的进程。随着时间的推移，这些幽灵进程会消耗大量内存。