HttpClient 4.0.1 - how to release connection?

Question

I have a loop over a bunch of URLs, for each one I'm doing the following:

private String doQuery(String url) {

  HttpGet httpGet = new HttpGet(url);
  setDefaultHeaders(httpGet); // static method
  HttpResponse response = httpClient.execute(httpGet);   // httpClient instantiated in constructor

  int rc = response.getStatusLine().getStatusCode();

  if (rc != 200) {
    // some stuff...
    return;
  }

  HttpEntity entity = response.getEntity();

  if (entity == null) {
    // some stuff...
    return;
  }

  // process the entity, get input stream etc

}

The first query is fine, the second throws this exception:

Exception in thread "main" java.lang.IllegalStateException: Invalid use of SingleClientConnManager: connection still allocated. Make sure to release the connection before allocating another one. at org.apache.http.impl.conn.SingleClientConnManager.getConnection(SingleClientConnManager.java:199) at org.apache.http.impl.conn.SingleClientConnManager$1.getConnection(SingleClientConnManager.java:173)......

This is just a simple single-threaded app. How can I release this connection?

Answer 1

The recommended way, by Httpcomponents 4.1, is to close connection and release any underlying resources:

EntityUtils.consume(HttpEntity)

where HttpEntity passed is a response entity.