HttpClient stuck without any exception

As of version 4.4, both answers by users user2393012 and Stephen C have been deprecated. I'm not sure if there is another way of doing it, but the way I do it is by using a builder paradigm, HTTPClientBuilder.

Ex.

HttpClients.custom().setConnectionTimeToLive(1, TimeUnit.MINUTES).build()

A very similar (it actually might have been OP's problem) problem to what OP mentioned also happens but is due to Apache setting the default concurrent connections to only two connections per client. The solution to this would be to increase the max connections or close them if you can.

To increase the max connections:

HttpClients.custom().setMaxConnPerRoute(100000).build()

To close connections, you can use a BasicHttpClientConnectionManager and call on the close method for

This code is now deprecated (get HttpParams, etc). A better way is:

RequestConfig defaultRequestConfig = RequestConfig.custom()
    .setCookieSpec(CookieSpecs.BEST_MATCH)
    .setExpectContinueEnabled(true)
    .setStaleConnectionCheckEnabled(true)
    .setTargetPreferredAuthSchemes(Arrays.asList(AuthSchemes.NTLM, AuthSchemes.DIGEST))
    .setProxyPreferredAuthSchemes(Arrays.asList(AuthSchemes.BASIC))
    .build();

HttpGet httpGet = new HttpGet(url);    
RequestConfig requestConfig = RequestConfig.copy(defaultRequestConfig)
    .setSocketTimeout(5000)
    .setConnectTimeout(5000)
    .setConnectionRequestTimeout(5000)
    .build();
httpGet.setConfig(requestConfig);