代码无弹窗判断设备是否root

public class RootUtil {
private final static String TAG = "RootUtil";

/** 判断手机是否root，不弹出root请求框<br/> */
public static boolean isRoot() {
String binPath = "/system/bin/su";
String xBinPath = "/system/xbin/su";
if (new File(binPath).exists() && isExecutable(binPath))
return true;
if (new File(xBinPath).exists() && isExecutable(xBinPath))
return true;
return false;
}

private static boolean isExecutable(String filePath) {
Process p = null;
try {
p = Runtime.getRuntime().exec("ls -l " + filePath);
// 获取返回内容
BufferedReader in = new BufferedReader(new InputStreamReader(
p.getInputStream()));
String str = in.readLine();
Log.i(TAG, str);
if (str != null && str.length() >= 4) {
char flag = str.charAt(3);
if (flag == 's' || flag == 'x')
return true;
}
} catch (IOException e) {
e.printStackTrace();
}finally{
if(p!=null){
p.destroy();
}
}
return false;
}
}