What behavior would you expect if you provide an empty Graph to a Layout? I suppose we could test for that (and throw a different exception), but it seems like a pretty unlikely circumstance, and a NPE seems not unreasonable.
Unless you have a good reason why this should be different, I'm not inclined to change this.
As for the compilation problem: maven does that every time I call it the first time; I don't know why. Try running the maven invocation again, it will probably work.
Joshua
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What behavior would you expect if you provide an empty Graph to a Layout? I suppose we could test for that (and throw a different exception), but it seems like a pretty unlikely circumstance, and a NPE seems not unreasonable.
Unless you have a good reason why this should be different, I'm not inclined to change this.
As for the compilation problem: maven does that every time I call it the first time; I don't know why. Try running the maven invocation again, it will probably work.
Joshua