问题描述
我在我当前的项目中使用 com.sun.net.httpserver.HttpsServer 处理客户端身份验证等。目前它只打印出客户端地址/端口，以便我可以检查是否有一个TCP连接用于多个请求（ keep-alive ）或者是否为每个请求建立了新连接（因此是新的每次都进行SSL握手）。当我使用FireFox对服务器发出多个请求时，我可以看到keep-alive正在运行。所以服务器部分可以正常使用GET和POST请求。
I am using com.sun.net.httpserver.HttpsServer in my current project which deals with client-authentification etc.. Currently it only prints out the clients address/port, so that I can check if one TCP-connection is used for multiple requests (keep-alive) or if a new connection is established for every request (and thus a new SSL-handshake is made every time). When I use FireFox to make multiple request against the server I can see that keep-alive is working. So the server part works fine with GET and POST-requests.
如果我使用 HttpURLConnection 来提出请求服务器（在这种情况下使用否 SSL） keep-alive 也可以工作：只为多个顺序启动的请求建立了一个连接。
If I use HttpURLConnection to make a request against the Server (in this case using no SSL) keep-alive works, too: Only one connection is established for multiple sequentially started requests.
但如果我使用 HttpsURLConnection （使用完全相同的代码，但使用 SSL）则 keep-alive 不再有效了。因此，对于每个请求，建立一个新连接，虽然我使用相同的 SSLContext （以及 SSLSocketFactory ）：
But if I use HttpsURLConnection (using exactly the same code, but using SSL) then keep-alive is not working anymore. So for each request a new connection is established, although I am using the same SSLContext (and SSLSocketFactory):
// URL myUrl = ...
// SSLContext mySsl = ...
HttpsURLConnection conn = (HttpsURLConnection) myUrl.openConnection();
conn.setUseCaches(false);
conn.setSSLSocketFactory(mySsl.getSocketFactory());
conn.setRequestMethod("POST");
// send Data
// receive Data
如何强制 HttpsURLConnection 使用 keep-alive 因为许多请求会导致许多SSL握手，这是一个真正的性能问题？
How do I force HttpsURLConnection to use keep-alive because many requests will lead to many SSL-handshakes which is a real performance issue?
更新（2012-04-02）：
而不是每次调用 mySsl.getSocketFactory（）我试图缓存 SSLSocketFactory 。但没有改变。问题仍然存在。
Update (2012-04-02):Instead of calling mySsl.getSocketFactory() each time, I tried to cache the SSLSocketFactory. But nothing changed. The problem still exists.
推荐答案
我无法使用 HttpsUrlConnection 。但Apache的HTTP客户端可以很好地处理SSL连接的保持活动状态。
I couldn't get it working with HttpsUrlConnection. But Apache's HTTP client handles keep-alive with SSL connections very well.
这篇关于HttpsUrlConnection和keep-alive的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！