post流文件上传

　　

path url

file 文件

　　

public static  String connectHttpsByPost(String path, File file) throws IOException, NoSuchAlgorithmException, NoSuchProviderException, KeyManagementException {
    URL urlObj = new URL(path);
    //连接
    HttpURLConnection con = (HttpURLConnection) urlObj.openConnection();
    String result = null;
    con.setDoInput(true);

    con.setDoOutput(true);

    con.setUseCaches(false); // post方式不能使用缓存

    // 设置请求头信息
    con.setRequestProperty("Connection", "Keep-Alive");
    con.setRequestProperty("Charset", "UTF-8");
    // 设置边界
    String BOUNDARY = "----------" + System.currentTimeMillis();
    con.setRequestProperty("Content-Type",
            "multipart/form-data; boundary="
                    + BOUNDARY);

    // 请求正文信息
    // 第一部分：
    StringBuilder sb = new StringBuilder();
    sb.append("--"); // 必须多两道线
    sb.append(BOUNDARY);
    sb.append("\r\n");
    sb.append("Content-Disposition: form-data;name=\"media\";filelength=\"" + file.length() + "\";filename=\""

            + file.getName() + "\"\r\n");
    sb.append("Content-Type:application/octet-stream\r\n\r\n");
    byte[] head = sb.toString().getBytes("utf-8");
    // 获得输出流
    OutputStream out = new DataOutputStream(con.getOutputStream());
    // 输出表头
    out.write(head);

    // 文件正文部分
    // 把文件已流文件的方式 推入到url中
    DataInputStream in = new DataInputStream(new FileInputStream(file));
    int bytes = 0;
    byte[] bufferOut = new byte[1024];
    while ((bytes = in.read(bufferOut)) != -1) {
        out.write(bufferOut, 0, bytes);
    }
    in.close();
    // 结尾部分
    byte[] foot = ("\r\n--" + BOUNDARY + "--\r\n").getBytes("utf-8");// 定义最后数据分隔线
    out.write(foot);
    out.flush();
    out.close();
    StringBuffer buffer = new StringBuffer();
    BufferedReader reader = null;
    try {
        // 定义BufferedReader输入流来读取URL的响应
        reader = new BufferedReader(new InputStreamReader(con.getInputStream()));
        String line = null;
        while ((line = reader.readLine()) != null) {
            buffer.append(line);
        }
        if (result == null) {
            result = buffer.toString();
        }
    } catch (IOException e) {
        System.out.println("发送POST请求出现异常！" + e);
        e.printStackTrace();
    } finally {
        if (reader != null) {
            reader.close();
        }
    }
    return result;
}