java更改android文件权限--待验证

public static boolean runRootCommand(String command) { // "chmod 777 " +
        // destFile.getAbsolutePath()--/system/etc/
        Process process = null;
        DataOutputStream os = null;
        try {
            process = Runtime.getRuntime().exec("su");
            os = new DataOutputStream(process.getOutputStream());
            os.writeBytes(command + "\n");
            os.writeBytes("exit\n");
            os.flush();
            process.waitFor();
        } catch (Exception e) {
            Log.d("*** DEBUG ***", "Unexpected error - Here is what I know: "
                    + e.getMessage());
            return false;
        } finally {
            try {
                if (os != null) {
                    os.close();
                }
                process.destroy();
            } catch (Exception e) {
                // nothing
            }
        }
        return true;
    }