[Java] Runtime Exec

经常用到Runtime的exec方法，记录一下标准用法，便于以后复制代码。

        Process process;
        String cmd = "cat /sys/devices/virtual/mxc_edid_class/mxc_edid_dev/timing";
        StringBuffer sb = new StringBuffer("");
        try {
            process = Runtime.getRuntime().exec("su");
            String line = null;
            DataOutputStream dos = new DataOutputStream(
                    process.getOutputStream());
            dos.writeBytes(cmd + "\n");
            dos.flush();
            dos.writeBytes("exit\n");
            dos.flush();
            BufferedReader bf = new BufferedReader(new InputStreamReader(
                    process.getErrorStream()));
            while ((line = bf.readLine()) != null) {
            }
            BufferedReader bf2 = new BufferedReader(new InputStreamReader(
                    process.getInputStream()));
            while ((line = bf2.readLine()) != null) {
                sb.append(line);
            }
            process.waitFor();
        } catch (Exception e) {
            e.printStackTrace();
            return;
        }