I am working on a course project for a software engineering class that generally deals with "Usability of APIs". I have created some metrics that I wish to run a few Java APIs through and see how they measure up.
To test out my metrics (for example, on average how many parameters are in each method call), I need to run some "good" and "bad" APIs through it. I'm sure everyone has some specific parts of the Java API (say, XML for example) that they think is either hard to use or just not done very well. I would be interested in hearing what everyone's pet peeves are about the Java API, but I am more interested in hearing complaints about third-party APIs that are really bad (for example, an imaging library that you've used in the past).
So, what is everyone's most hated Java API, as well as most hated third-party API? Also, if you could give some indication of why you think it is especially bad ("I can never remember if I should call delete or remove"), that would be a huge help for my project.