Develop Reference

How to reuse SSL session when I implement trust self-certificate in HttpClient?

I reference this page and implement trust slef-certificate as follows,
SchemeRegistry schemeRegistry = new SchemeRegistry();
// http scheme
schemeRegistry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
// https scheme
schemeRegistry.register(new Scheme("https", new EasySSLSocketFactory(), 443));
HttpParams params = new BasicHttpParams();
params.setParameter(ConnManagerPNames.MAX_TOTAL_CONNECTIONS, 30);
params.setParameter(ConnManagerPNames.MAX_CONNECTIONS_PER_ROUTE, new ConnPerRouteBean(30));
params.setParameter(HttpProtocolParams.USE_EXPECT_CONTINUE, false);
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
ClientConnectionManager cm = new ThreadSafeClientConnManager(params, schemeRegistry);
The EasySSLSocketFactory is here, and the EasyX509TrustManager is here.
I found that it would have a lot of SSL hello handshake.
After my studies, this situation may be reduced by using SSLSessionCache.
I search in the forum, but the solution almost using normal ssl connecting not using trust self-certificate.
How can I use SSLSessionCache when I implement trust self-certificate in HttpClient?

Is creating HttpClient expensive?

I had seen a few examples in Android implement maybeCreateHttpClient(), especially in Google sample, which it does is to check if HttpClient object is instantiated, if not, instantiate it, and reuse it.
Why this approach? Is creating new HttpClient expensive?

Use a connection pool (eg. ThreadSafeClientConnManager) to manage your clients.
HttpParams params = new BasicHttpParams();
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, HTTP.DEFAULT_CONTENT_CHARSET);
HttpProtocolParams.setUseExpectContinue(params, true);
SchemeRegistry registry = new SchemeRegistry();
registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
registry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
ClientConnectionManager connman = new ThreadSafeClientConnManager(params, registry);
client = new DefaultHttpClient(connman, params);
client is a singleton object which can be reused, to fire a request:
HttpResponse response = client.execute(new HttpGet(URL));

A HttpClient is fairly large and complex object. You might make tens (or probably more) http calls in your app. If you created a new one for each http request you would quickly run into memory problems and would certainly notice garbage collection slow downs.
The http client is a generic component to help you make http calls, just reuse it. There is no reason not too.

ClientProtocolException thrown when using ThreadSafeClientConnManager to execute a http post

HttpParams params = new BasicHttpParams();
ConnManagerParams.setMaxConnectionsPerRoute(params, new ConnPerRouteBean(100));
ConnManagerParams.setMaxTotalConnections(params, 100);
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setUseExpectContinue(params, false);
HttpProtocolParams.setContentCharset(params, HTTP.DEFAULT_CONTENT_CHARSET);
HttpConnectionParams.setConnectionTimeout(params, CONNECTION_TIMEOUT);
HttpConnectionParams.setSoTimeout(params, REQUEST_TIMEOUT);
SchemeRegistry registry = new SchemeRegistry();
registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), PORT));
ThreadSafeClientConnManager cm = new ThreadSafeClientConnManager(params, registry);
client = new DefaultHttpClient(cm, params);
HttpClientParams.setCookiePolicy(client.getParams(), CookiePolicy.BROWSER_COMPATIBILITY);
When my app waits for several seconds, the next post will be failed because of the ClientProtocolException.
By wireshark, I find that android also use the previous tcp socket to execute the post, but that socket is ended with a FIN from the server. And the next several posts will succeed because a new socket establish.
is there anyone know how to solve the problem??

I had a similar problem. Try adding this line :
System.setProperty("http.keepAlive", "false");
before you make the connection. Might solve your problem.

Android ThreadSafeClientConnManager Timeouts?

I'm using a ThreadSafeClientConnManager to perform simultaneous requests in background threads on Android, set up with:
HttpParams params = new BasicHttpParams();
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, HTTP.DEFAULT_CONTENT_CHARSET);
HttpProtocolParams.setUseExpectContinue(params, true);
SchemeRegistry registry = new SchemeRegistry();
registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
registry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
ClientConnectionManager connman = new ThreadSafeClientConnManager(params, registry);
client = new DefaultHttpClient(connman, params);
And executing requests with (note that I'm using outh-signpost):
HttpGet request = new HttpGet("https://" + API_HOST + "/" + API_VERSION + path);
OAuthConsumer consumer = new CommonsHttpOAuthConsumer(key, secret);
consumer.sign(request);
HttpResponse response = client.execute(request);
The problem is that after a while I start getting
java.net.SocketException: The operation timed out
Do I need to do something to explicitly release the connection after the request?

From the usage guide of apache httpclient, you need to make sure to consume all content on any pooled resource to guarantee it returns to the pool to be available for other threads later on -
http://hc.apache.org/httpcomponents-core-4.0.1/tutorial/html/fundamentals.html#d0e244
In case there's an exception thrown by the underlying library, it is best to abort the HttpMethod that you were trying to run, in which case the connection will be terminated.

Android and SSL - checking certificate validity

I've got the following code making SSL work with my HttpClient connections and such
SchemeRegistry schemeRegistry = new SchemeRegistry();
schemeRegistry.register(new Scheme("https",
SSLSocketFactory.getSocketFactory(), 443));
HttpParams params = new BasicHttpParams();
SingleClientConnManager mgr = new SingleClientConnManager(params, schemeRegistry);
HttpClient client = new DefaultHttpClient(mgr, params);
However, does this actually validate the cert? It seems like there should be more to it.

Nevermind, the above code does indeed validate the certificate. I tried it with some random self signed certs for different sites, and it failed.