There are quite some tutorials around about building and exposing a RESTful Webservice, but some of them are outdated and make you wade through complex dependencies and tinkering with deployment descriptors and web.xml files. But using RESTeasy, the JBoss implementation that is fully compliant with the JAX-RS 2.0 JCP specification, and Eclipse you can build a simple webservice (“hello world”) with less than 10 lines of sourceode with annotations and no web.xml used in a few minutes and run it on Wildfly.
Lets build a webservice that creates random numbers.
There are 2 crucial phases you want to look under the hood of your running Glassfish or inside the JVM underneath: Performance Tuning and Health Monitoring during production.
With JMX (Java Management Extensions, Wikipedia) at hand, there are a few options to choose from.
The graphical monitoring tool is great for local deployment, it allows you to connect to a JVM on the same host or a remote host. It creates line graphs for your for all relevant from the moment you connect, it is perfect to observe a server while you do some testing or other actions, though it does not record any values while you are not connected. I have a hard time to get it running on a remote server and I do not favour the ‘open’ approach (see previous blog entry) which allows anyone to access the JVM with the disabled authentication settings. I also had situations where the JVM was frozen and it was no longer possible to access the JVM for monitoring, here I would rather have snapshots before the problem started together with server.log.
Glassfish Rest Interface
Note: You need to enable the areas you want to monitor with the admin console (or the asadmin command line) because per default all are OFF. Continue reading