HttpURLConnection.setRequestProperty的作用

设置http请求头

HttpURLConnection.setRequestProperty（String key，String value）;  

这个我居然都忘记了，哎~真是岁数大了，心好累。。。 

例如：下面就是一个完整的原始网络请求方式

HttpURLConnection conn = null;
                try {
                    URL my_url = new URL(log());
                    //得到connection对象。
                    conn = (HttpURLConnection) my_url.openConnection();
                    //允许写出
                    conn.setDoOutput(true);
                    //允许读入
                    conn.setDoInput(true);
                    //设置请求方式
                    conn.setRequestMethod("POST");
                    conn.setUseCaches(false);
                    conn.setConnectTimeout(60 * 1000);
                    conn.setReadTimeout(60 * 1000);
                    //设置请求头
                    conn.setRequestProperty("Charsert", "UTF-8");
                    conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");//设置参数类型是json格式
                    conn.setRequestProperty("Connection", "Keep-Alive");
                    conn.setRequestProperty("logType", "base");
                    //连接网络。请求行，请求头的设置必须放在网络连接前
                    conn.connect();
                    BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(conn.getOutputStream(), "UTF-8"));
                    writer.write(String.valueOf(hashMap));
                    writer.close();
                    //得到响应码
                    int responseCode = conn.getResponseCode();
                    MyLogcat.e("网络传输" + responseCode + "***" + conn.getResponseMessage() + String.valueOf(hashMap));
                    if (responseCode == 200) {
                        //得到响应流
                        InputStream inputStream = conn.getInputStream();
                        //将响应流转换成字符串
                        String returnLine = getStringFromInputStream(inputStream);
                        String str = "Success" + conn.getResponseCode() + "---" + conn.getResponseMessage() + "---" + returnLine;
                    } else {
                        String str = "Error" + conn.getResponseCode() + "---" + conn.getResponseMessage();
                        
                    }

                } catch (Exception e) {
                    e.printStackTrace();
                } finally {
                    if (conn != null) {
                        conn.disconnect();
                    }
                }


/**
     * 通过字节输入流返回一个字符串信息
     */
    private static String getStringFromInputStream(InputStream is) throws Exception {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = 0;
        while ((len = is.read(buffer)) != -1) {
            baos.write(buffer, 0, len);
        }
        is.close();
        // 把流中的数据转换成字符串, 采用的编码是: utf-8
        String status = baos.toString();
        baos.close();
        return status;
    }