Apache HttpClient timeout

user_698334 0
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Is there a way to specify a timeout for the whole execution of HttpClient?

I have tried the following:

httpClient.getParams().setParameter("http.socket.timeout", timeout * 1000);
httpClient.getParams().setParameter("http.connection.timeout", timeout * 1000);
httpClient.getParams().setParameter("http.connection-manager.timeout", new Long(timeout * 1000));
httpClient.getParams().setParameter("http.protocol.head-body-timeout", timeout * 1000);

It actually works fine, except if a remote host sends back data - even at one byte/second - it will continue to read forever! But I want to interrupt the connection in 10 seconds max, whether or not the host responds.

apache-httpclient-4.x timeout java
7 Answers

Timer is evil! Using timer or executor or any other mechanism which creates a thread/runnable object per request is a very bad idea. Please think wisely and don't do it. Otherwise you will quickly run into all kind of memory issues with more or less real environment. Imagine 1000 req/min means 1000 threads or workers / min. Poor GC. The solution I propose require only 1 watchdog thread and will save you resources time and nerves. Basically you do 3 steps.

  1. put request in cache.
  2. remove request from cache when complete.
  3. abort requests which are not complete within your limit.

your cache along with watchdog thread may look like this.

import org.apache.http.client.methods.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.stream.*;

public class RequestCache {

private static final long expireInMillis = 300000;
private static final Map<HttpUriRequest, Long> cache = new ConcurrentHashMap<>();
private static final ScheduledExecutorService exe = Executors.newScheduledThreadPool(1);

static {
    // run clean up every N minutes
    exe.schedule(RequestCache::cleanup, 1, TimeUnit.MINUTES);
}

public static void put(HttpUriRequest request) {
    cache.put(request, System.currentTimeMillis()+expireInMillis);
}

public static void remove(HttpUriRequest request) {
    cache.remove(request);
}

private static void cleanup() {
    long now = System.currentTimeMillis();
    // find expired requests
    List<HttpUriRequest> expired = cache.entrySet().stream()
            .filter(e -> e.getValue() > now)
            .map(Map.Entry::getKey)
            .collect(Collectors.toList());

    // abort requests
    expired.forEach(r -> {
        if (!r.isAborted()) {
            r.abort();
        }
        cache.remove(r);
      });
    }
  }

and the following sudo code how to use cache

import org.apache.http.client.methods.*;

public class RequestSample {

public void processRequest() {
    HttpUriRequest req = null;
    try {
        req = createRequest();

        RequestCache.put(req);

        execute(req);

    } finally {
        RequestCache.remove(req);
    }
  }
}
user_32115320
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