Monday, August 18, 2008

Capturing traffic from JAX-WS RI, or indeed any java client, on localhost

Although this post focuses on the HTTP Analyzer in JDeveloper, well because I work on it, this also contains information that is relavent to other testing tools such a tcpmon and SOAPUI.

Normally in a development situation where you have everything on the same box you can simply use "localhost" as the domain name. This has a lot of advantages when working in a source controlled environment as the same strings can be used on different machines. So in this scenario you have the client, some kind of HTTP monitoring proxy, and the server running on the same machine.

So when you start the client from inside of JDeveloper we set the right proxy environment settings; but you can expect them to look something like:


Now you would expect this mean that any request to any host will be sent via the proxy. But as noted in sun bug 6737819 the default ProxySelector will never proxy any requests to "localhost" even if you explicitly set "nonProxyHosts". This is of course a major pain for tools developers and users like.

Fortunately there is a workaround and that is to use "localhost.localdomain" instead. This is just a synomn for localhost and the proxy selector in java is not clever enough to recognize this as being the same as localhost. (Also I suspect it doesn't recognize :::1 or any of the other ipv6 localhost options)

When users get there sweaty hands on the next version of JDeveloper this is why we have moved to defaulting to "localhost.localdomain" rather than just plain old "localhost". Not because we are trying to be difficult or obtuse. :-)


Turns out this doesn't work so well on OS X. This is because the "/etc/hosts" file is missing localhost.localdomain entry. You can fix this by editing this file as root. ("sudo vi /etc/hosts") You need to alter the line:   localhost

to be   localhost localhost.localdomain

Please be carefull with this file, if you mess it up you machine may not boot properly. I have logged apple bug 6158676 to track this issue.

Wednesday, August 6, 2008

VW Polo Bluemotion 2

So my wife bought a VW Polo earlier on this year from the bluemotion range. We wanted something really quite fuel efficent I have have to say we are really quite pleased with how it lives up to the hype.

Based on the data provided by the onboard computer we average over 70 mpg, on longer motor way journeys it is not unheard of to average over 80 mpg. (Note these are UK not US MPG. Use a converter such as this one).

Remember this is the model with air-con and leather trims so it is not some eco-hay waggon. The variable speed turbo charger also means that is performs much better than you would expect from a diesel. Indeed I enjoy driving it more than my other sportier car in many ways.

And yes you could quite happily drive from London to Edinburgh on one tank of fuel, and avoid the congestion charge in the future due to its very low CO2 emissions.

More JAX-RI secrets @SchemaValidation

One of the nice things about the RI is that you keep on coming across nice little extensions in the com.sun.xml.* tree. Unfortunately many are not even documented so you only find they by reading the daily posts on the jax-ws forum.

Take for example which allows you to validate incoming schemas. Many might say that this is a needless hit and duck typing is fine; but in certain debugging cases it would be nice to have some control over the validation failure process.

By default it uses but you can replace this with your own implementation to perform what-ever tracing and debuging you need. Normally you would have any control of this as the service would probably fail before the databinding stage.

@ValidationErrorHandler(handler = CustomValidationFailureLogging.class)
public OrderProcessing

Well worth downloading the source code to see what goodies you are missing?