http的post方法

class ReadByPost extends Thread {    @Override    public void run() {        super.run();        String targetUrl = "https://api.douban.com/v2/book/search";        try {            URL url = new URL(targetUrl);            HttpURLConnection con = (HttpURLConnection) url.openConnection();            con.addRequestProperty("encoding", "UTF-8");            con.setDoInput(true);            con.setDoOutput(true);            con.setRequestMethod("POST");            OutputStream os = con.getOutputStream();            OutputStreamWriter osw = new OutputStreamWriter(os);            BufferedWriter bw = new BufferedWriter(osw);            bw.write("q=软件工程");            bw.flush();            InputStream is = con.getInputStream();            InputStreamReader isr = new InputStreamReader(is);            BufferedReader br = new BufferedReader(isr);            String line;            StringBuilder sb = new StringBuilder();            while ((line = br.readLine()) != null) {                sb.append(line);            }            bw.close();            osw.close();            os.close();            br.close();            isr.close();            is.close();            System.out.println(sb.toString());        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }}