方案1：

        long result = 0L;
        try {
            String line;
            BufferedReader br = new BufferedReader(new FileReader("/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq"));
            if ((line = br.readLine()) != null) {
                result = Long.parseLong(line);
            }
            br.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

        return result;

方案2:

        String result = "";
        ProcessBuilder cmd;
        try {
            String[] args = {"/system/bin/cat", "/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq"};
            cmd = new ProcessBuilder(args);
            Process process = cmd.start();
            InputStream in = process.getInputStream();
            byte[] re = new byte[24];
            while (in.read(re) != -1) {
                result = result + new String(re);
            }
            in.close();
        } catch (IOException ex) {
            ex.printStackTrace();
            result = "N/A";
        }
        return result.trim();