Java 实现Http post请求

public String Post(String url, String reqMes) {

    String status = "";
    String responseStr = "";
    PrintWriter out = null;
    BufferedReader in = null;
        try {
            URL realUrl = new URL(url);
            // 打开和URL之间的连接
            URLConnection conn = realUrl.openConnection();
            HttpURLConnection httpUrlConnection = (HttpURLConnection) conn;
            // 设置请求属性
            httpUrlConnection.setRequestProperty("Content-Type", "application/json");
            httpUrlConnection.setRequestProperty("x-adviewrtb-version", "2.1");
            // 发送POST请求必须设置如下两行
            httpUrlConnection.setDoOutput(true);
            httpUrlConnection.setDoInput(true);
            // 获取URLConnection对象对应的输出流
            out = new PrintWriter(httpUrlConnection.getOutputStream());
            // 发送请求参数
            out.write(reqMes);
            // flush输出流的缓冲
            out.flush();
            httpUrlConnection.connect();
            // 定义BufferedReader输入流来读取URL的响应
            in = new BufferedReader(new    InputStreamReader(httpUrlConnection.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                    responseStr += line;
            }
            status = new Integer(httpUrlConnection.getResponseCode()).toString();
//          System.out.println("status=============="+status);
//          System.out.println("response=============="+responseStr);
        } catch (Exception e) {
            System.out.println("发送 POST 请求出现异常！" + e);
        }
        // 使用finally块来关闭输出流、输入流
        finally {
            try {
                if (out != null) { out.close();}
                if (in != null) {in.close();}
            } catch (Exception ex) {
                    ex.printStackTrace();
        }
    }
        return responseStr;
}

方法中的参数第一个是请求的地址，第二个是想要传递的内容，或者数据。