I think it was originally started under the Apache Axis project, but it is now hosted on java.net (click here to go to the tcpmon homepage).
While there are also commercial tools to do this, its always nice to find a simple and free tool that gets the job done. Its a pretty intuitive utility, that basically acts as a go-between for the client and server, echoing any tcp traffic that passes through it.
I won't go into too many details (there are plenty of other tutorials available on the internet, just a google away), but one thing worth pointing out is how to configure the target host and your client for the web service (since most of the examples don't contain any path info on the URLs, which is pretty common for any web service requests).
First, if the URL of your web service is http://my.service.com/services/myservice, configure tcpmon like this:
And then, when you create your client stub for the web service (if you are using Axis2 and pass in a String for the target endpoint), create it this way:
MyWebServiceStub stub = new MyWebServiceStub("http://localhost/services/myservice");Instead of the normal way, without the tcpmon as the "man-in-the-middle".
MyWebServiceStub stub = new MyWebServiceStub("http://my.service.com/services/myservice");A couple of other points worth mentioning:
- It can run as a standalone app (from a downloaded jar file) or over the web via JNLP. The 'official' version is also available as a NetBeans plug-in.
- Some enterprising developers also ported a plug-in version for eclipse available here (thanks guys). The main benefit here is that it is just runnable within eclipse, with the GUI visible as a console view. Installation is simple - just drop the jar file into the plugin folder for eclipse (.../ECLIPSE_HOME/plugin/).
- One thing I noticed within the GUI for the eclipse plug-in is that it also seems to have support for a proxy server (as a firewall pass through to external URLs). I don't see similar configuration options on the standalone version (not sure if this is a difference or not, but thought it was worth mentioning).
- If you run into trouble getting everything connected (getting a java.net.UnknownHostException), consider trying both the listener and target port to 80 (in case there are firewalls, or other security settings affecting communication over nonstandard ports that are often suggested in the tutorials).
- It can also be beneficial to just try configuring connectivity to a simple html page, to understand the setup before trying to snoop on a web service (paths, etc.)
