帮忙瞥几行代码

Process suProcess;        try {            suProcess = Runtime.getRuntime().exec("/system/bin/sh");            DataOutputStream dos = new DataOutputStream(suProcess.getOutputStream());            dos.writeBytes("cat /sdcard/sz.apk>/sdcard/pma/sz.apk");            dos.writeBytes("exit\n");            dos.flush();            suProcess.waitFor();        } catch (IOException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }  catch (InterruptedException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }