CODEWITHSUNDEEP
apache-httpclient-4.x
Macilias
Macilias

Reputation: 3533

httpClient.getConnectionManager() is deprecated - what should be used instead if i want to react to poolstats?

before HttpClient we had a thread going on, which checked whether there are MAX_TOTAL_CONNECTIONS reached. It looked like this:

    @Override
    public void run() {
        try {
            while (!shutdown) {
                synchronized (this) {
                    wait(60000);

                    // this is an emergency check. if all connections have been exhausted, then shutdown the old connection manager and instantiate a new http client
                    PoolingHttpClientConnectionManager tsc = (PoolingHttpClientConnectionManager) connMgr;

                    // previously here was : tsc.getConnectionsInPool() == MAX_TOTAL_CONNECTIONS
                    // since the PoolingClientConnectionManager has no clear replacement multiple candidates:
                    // 1. tsc.getTotalStats().getLeased()       (number of persistent connections tracked by the connection manager currently being used to execute requests.)  (Available + Leased)
                    // 2. tsc.getTotalStats().getPending()      (number of connection requests being blocked awaiting a free connection.)
                    // 3. tsc.getTotalStats().getAvailable()  (number idle persistent connections.)
                    // 4. tsc.getTotalStats().getMax()              (maximum number of allowed persistent connections.)
                    // because of the statement: The total number of connections in the pool is equal to available plus leased - will go to use the sum of them both.

                    PoolStats poolStats = tsc.getTotalStats();
                    if (poolStats.getAvailable() + poolStats.getLeased() == MAX_TOTAL_CONNECTIONS) {
                        System.out.println("Error in HttpClient: It seems as if all connections are exhausted: will create new HttpClient now!");
                        tsc.shutdown();
                        httpAgent = initializeDefaultHttpClient();
                    }
                }
            }
        }
        catch (InterruptedException ex) {
            // terminate
        }
        catch (IOException e) {
            // error
        }
    }


    public void shutdown() {
        shutdown = true;
        synchronized (this) {
            notifyAll();
        }
    }
}

Now i know that we should use the CloseableHttpClient which has a Method ".close()". But i don't seam no to have any possibility to check whether i want to close or not.

Does someone know how to get best around that problem?

Thx

Mac

Upvotes: 0

Views: 3643

Answers (1)

ok2c
ok2c

Reputation: 27538

There is absolutely nothing that stops you from keeping a reference to the underlying connection pool if required

PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager();
CloseableHttpClient client = HttpClients.custom()
        .setConnectionManager(cm)
        .build();
PoolStats totalStats = cm.getTotalStats();

Upvotes: 1

Related Questions