检查是否批准了root？

Question

try {
            Runtime.getRuntime().exec("su");
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            altDialog.setTitle("No Root");
            altDialog
                    .setMessage("I am afraid I have been unable to execute the su binary. Please check your root status.");
            altDialog.setCancelable(false);
            altDialog.setButton("Exit App",
                    new DialogInterface.OnClickListener() {

                        @Override
                        public void onClick(DialogInterface arg0, int arg1) {
                            // TODO Auto-generated method stub
                            Log.e("Android .img Flasher",
                                    "Exiting due to root error");
                            finish();
                        }
                    });
        }

我如何能够检查root是否真的被授予？

另请注意，如何使用runtime.getruntime.exec()命令存储命令的输出？

Answer 1

你可以使用下面的代码。我编写它是为了通用命令，但它也可以与su命令一起使用。如果命令成功，则返回命令输出（或错误）。

public static boolean execCmd(String command, ArrayList<String> results){
    Process process;
    try {
        process = Runtime.getRuntime().exec(new String [] {"sh", "-c", command});
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    } 

    int result;
    try {
        result = process.waitFor();
    } catch (InterruptedException e1) {
        e1.printStackTrace();
        return false;
    }

    if(result != 0){ //error executing command
        Log.d("execCmd", "result code : " + result);
        String line; 
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getErrorStream())); 
        try {
            while ((line = bufferedReader.readLine()) != null){
                if(results != null) results.add(line);
                Log.d("execCmd", "Error: " + line);
            }
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
        return false;
    }

    //Command execution is OK
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream())); 

    String line; 
    try {
        while ((line = bufferedReader.readLine()) != null){
            if(results != null) results.add(line);
            Log.d("execCmd", line);
        }
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    }
    return true;
}

可以用两个参数来调用它：

• 命令-带有要执行命令的字符串
• results-空ArrayList返回命令输出。如果为null，则不返回输出。

//Array list where the output will be returned
ArrayList<String> results = new ArrayList<String>();
//Command to be executed
String command = "su -c ls";
boolean result = execCmd(command,results);
//result returns command success
//results returns command output