JAMon lives on !

I have been a big fan of JAMon tool for monitoring Java applications.It is lightweight and has a cool UI that gives you the stats you want. Also it is very clean and simple to use.

The last time I used JAMon was around 5 years ago. I was suprised to see that the project is still alive and kicking and has a few updates that make it even more interesting. I liked the concept of Listeners, which makes it easy to customoize JAMon.

The one thing that was missing in JAMon in the yesteryears was a consolidation app to read stats from multiple nodes in a cluster and present in on a unified dashboard. Luckily there seems to be a project called JARep that just does that. There is no much documentation available on JARep, but there is a good case study on DZone that explains how JARep works.

The case study is available at: http://architects.dzone.com/articles/case-study-performance-tuning--0

Though I have experiemented with a lot of other tools, I found JAMon to be the best and simplest. One can get it up and running in a project with a few minutes.

JAMon JDBCMonProxy -getting the orginal connection

While using JAMon to monitor SQL perf stats, we faced a small problem - at one place we needed the underlying OracleConnection object and not the proxy, as we were calling a vendor-specific method on it.
Thankfully the JAMon API MonProxy object has a "getMonitoredObject()" method through which I could get hold of the OracleConnection object and use it.

Here is the sample code snippet: (just in case someone else needs it :)

// we need to do this as the 'setEndToEndMetrics' 
// method is only available on an OracleConnection.
   if (Proxy.isProxyClass(connection.getClass()))// if a dynamic proxy object
   {
    InvocationHandler invocationHandler = 
                   Proxy.getInvocationHandler(connection);
    Object monitoredObject = 
                   (MonProxy) invocationHandler).getMonitoredObject();
    ((OracleConnection) monitoredObject).
                    setEndToEndMetrics(metrics, (short) 0);
   }