How to cache a Memcached connection using the java spymemcached client - memcached

Question

I am learning how to cache objects using memcached with the spymemcached client from spymemcached examples
MemcachedClient c=new MemcachedClient(new InetSocketAddress("hostname", portNum));
// Store a value (async) for one hour
c.set("someKey", 3600, someObject);
// Retrieve a value (synchronously).
Object myObject=c.get("someKey");
I have noted that each time I want to cache or retrieve an object I create a new memcached client which am assuming is a new connection and that memcached has no connection pooling mechanism therefore users are advised to cache the connections to decrease overhead for reconnecting from this question opening closing and reusing connections.
My question is how do I cache this connection? Can someone please give me an example I can start from.
If you are wondering what I have tried, I tried to put my connection in the memcached but then I realized that I have to create a connection to get it. :)
Thanks in advance.

Answer 1

I have noted that each time I want to cache or retrieve an object I
create a new memcached client which am assuming is a new connection
Don't do this; spymemcache uses a single connection for ALL I/O to and from memcache; it's all done asychronously; from spymemcache docs...
Each MemcachedClient instance establishes and maintains a single
connection to each server in your cluster.
Just do the following once in your app; make sure the client is available to other services in your app so they can access it.
MemcachedClient memClient = new MemcachedClient(new InetSocketAddress(host, port));
Use memClient for I/O with memcache; no need to create a new instance of MemcachedClient each time; done. The link you provided answers all of your questions.
What is your deployment? web-app or standalone?

Answer 2

This just means that you should use reuse the connections that you open as opposed to opening a connection for each request. It doesn't make sense to store a connection instance in memcached.
Cacheing the connection in the case means caching it in your application (keeping it in memory and open), not actually storing the connection in memcached.

Answer 3

I did a little more research and stumbled on this question
Then I came up with my solution as,
first created a contextlistener
public class ContextListener implements ServletContextListener {
#Override
public void contextInitialized(ServletContextEvent sce) {
Memcached.createClient();
}
#Override
public void contextDestroyed(ServletContextEvent sce) {
}
}
then i added the listener to the deployment discriptor by adding these lines to web.xml
<listener>
<description>Used with memcached to initialize connection</description>
<listener-class>com.qualebs.managers.ContextListener</listener-class>
</listener>
I created a class Memcached and added these methods
static void createClient() {
try {
client = new MemcachedClient(new InetSocketAddress("localhost", 11211));
} catch (IOException ex) {
Logger.getLogger(Memcached.class.getName()).log(Level.SEVERE, ex.getMessage(), ex);
}
}
static MemcachedClient getClient() throws IOException {
return client;
}
Now anywhere I need to use memcached connection just call Memcached.getClient()
I hope that will help anybody else out there with the same question.