Question

我正在尝试将POST（主体中包含XML）发送到API，并获得返回的XML响应。我需要从响应正文（从ERROR元素中）获得确认或错误的详细信息。

我可以发送POST，它确实触发了API中的更改，但是我无法读取响应。

当我从邮递员手动发送POST时，我触发了API中的更改，并且我可以看到来自API的响应为text/html;charset=charset=utf-8

这是我当前的代码：

      URL url = new URL(urlString);

        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setDoOutput(true);

        OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());

        writer.write(xmlString);
        writer.flush();
        String line;
        BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
        while ((line = reader.readLine()) != null) {
            System.out.println(line);
        }
        writer.close();
        reader.close();

响应正文应采用以下格式：

<Root>
    <Session>
        <UserId>theUserID</UserId>
        <Password>thePassword</Password>
        <ERROR Status="0" Description="Logon Successful" />
    </Session>
    <ActivityList>
        <Activity Type="ReqUp" Incident="12345" ElapsedTime="350" 
      Description="example response" 
      Status="Complete">
            <ERROR Status="0" Description="OK" />
        </Activity>
    </ActivityList>
</Root>

当前/实际结果：
line显示为null

Answer 1

由于您希望xml从服务器返回，因此可能需要在请求中添加“ accept”标头，以告诉服务器您（客户端）将“接受” xml。从您的帖子中看来，默认值为html。

这可能对您有用：

  URL url = new URL(urlString);

  HttpURLConnection conn = (HttpURLConnection) url.openConnection();
  conn.setRequestProperty("accept", "application/xml");
  conn.setDoOutput(true);

  OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());

如果要将xml发送到服务器，则可能还需要添加“内容类型”标头，如下所示：

  conn.setRequestProperty("content-type", "application/xml");

ref：https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html

Answer 2

我的原始代码中存在一个错误，该错误阻止行形成null以外的任何形式。

正确的代码如下：

        URL url = new URL(urlString);

        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setRequestProperty("accept", "text/html");


        conn.setDoOutput(true);

        OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());

        writer.write(xmlString);
        writer.flush();
        String builtResponse = "";
        String line ="";
        BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
        while ((line = reader.readLine()) != null) {
            builtResponse += line;
        }
        writer.close();
        reader.close();

如何从HttpURLConnection POST获得响应

2 个答案: