《Android-编程实战》11-网络 Web服务

    HttpResponseCache httpResponseCache = HttpResponseCache.install(new File(getCacheDir, "http"), CACHE_SIZE);

private static final long MAX_FIXED_SIZE = 5 * 1024 * 1024;
private static final String CRLF = "\r\n";
/**
*  使用HTTP POST往服务器发送文件
*/
public int postFileToURL(File file, String mimeType, URL url) throws IOException {

   DataOutputStream requestData = null;
   try {
       long fileSize = file.length();
       String fileName = file.getName();

       // 创建一个随机边界符字符串
       Random random = new Random();
       byte[] randomBytes = new byte[16];
       random.nextBytes(randomBytes);
       String boundary = Base64.encodeToString(randomBytes, Base64.NO_WRAP);

       // 配置请求设置
       HttpURLConnection uc = (HttpURLConnection) url.openConnection();
       uc.setUseCaches(false);
       uc.setDoOutput(true);           // 设置可以发送数据
       uc.setRequestMethod("POST");

       // 设置HTTP header
       uc.setRequestProperty("Connection", "Keep-Alive");
       uc.setRequestProperty("Cache-Control", "no-cache");
       uc.setRequestProperty("Content-Type", "multipart/form-data;boundary="+boundary);

       // 如果文件大于max_fixed_size, 使用分块流模式
       if (fileSize > MAX_FIXED_SIZE){
           uc.setChunkedStreamingMode(0);
       }else{
           uc.setFixedLengthStreamingMode((int)fileSize);
       }

       // 打开文件方便读取
       FileInputStream fileIn = new FileInputStream(file);
       // 打开服务器连接
       OutputStream out = uc.getOutputStream();
       requestData = new DataOutputStream(out);

       // 开始写数据
       // 首先写入第一个边界符
       requestData.writeBytes("--" +boundary + CRLF);
       // 让服务器知道文件名
       requestData.writeBytes("Content-Disposition: form-data; name=\""+ fileName + "\"; filename=\""+fileName + CRLF);
       // 文件的MIME类型
       requestData.writeBytes("Content-Type: "+mimeType + CRLF);

       // 循环读取本地文件, 并写入服务器
       int bytesRead;
       byte[] buffer = new byte[8 * 1024];
       while((bytesRead = fileIn.read(buffer)) != -1){
           requestData.write(buffer, 0, bytesRead);
       }

       // 写入边界字符串, 表明已到文件结尾
       requestData.writeBytes(CRLF);
       requestData.writeBytes("--" +boundary +"--"+ CRLF);
       requestData.flush();

       return uc.getResponseCode();

   } catch (IOException e) {
       e.printStackTrace();
   }finally {
       if (requestData != null){
           requestData.close();
       }
       return -1;
   }

}

GET /websocket HTTP/1.1
Host: myserver.com
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Key: xxxxxxxxxxxxxxxxxx==
Sec-WebSocket-Protocol: chat
Sec-WebSocket-Version: 13
Origin: http://myserver.com

HTTP/1.1 101 Switching Protocols
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Accept: xxxxxxxxxxxxxxxxxxx=
Sec-WebSocket-Protocol: chat