java - 来自 HttpURLConnection 的输入流 : When to disconnect?

Question

以下构造方法应将 XML 从 URL 读取到 XML Document 对象中。虽然它已经起作用了，但我仍然怀疑它是否正确。

// Basic constructor method without exception handling
Feed(URL url) throws IOException, ParserConfigurationException, SAXException {
    HttpURLConnection httpcon = (HttpURLConnection) url.openConnection();
    httpcon.addRequestProperty("User-Agent", "Some User-Agent");

    InputStream inStream = httpcon.getInputStream();

    httpcon.disconnect();

    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    DocumentBuilder builder = factory.newDocumentBuilder();
    doc = builder.parse(inStream);
}

问题:

• 难道不应该先解析 InputStream 然后关闭 HttpURLConnection 吗？
• 在我尝试从 httpcon 获取某些内容之前，不应该有一个 httpcon.connect() 吗？

Answer 1

Shouldn't one first parse the InputStream and then close the HttpURLConnection?

是的，或者更确切地说关闭InputStream。

Shouldn't there be a http on.connect() before I try to get something from httpcon?

没有。它隐含在获取输入流中。

您发布的代码不正确，不应工作。应在断开连接之前读取输入流。实际上，只有当您想要防止连接池时才需要断开连接。