I've written/ported about 4300 lines of Java code so far - roughly 100 lines per day since I started in mid May. That's average of course, some days none, some days a lot more. (And some days it's probably been negative when I threw out code!)
There's probably nothing wrong with 100 lines of code per day. If that was new code it'd be pretty good, but with porting I'd expect higher productivity. Sometimes the conversion from C++ to Java is very straightforward and quick, other times I have to do a fair bit of redesign.
Assuming the Java code will end up half the size of the C++ code, or about 30,000 lines, at the current rate I have another approximately 260 days to go, or about 8 months. (Although I still have no idea if "half the size" will be accurate. Some things are smaller or available pre-built in Java, but others, like the btree code, are pretty much the same size.)
It's a good example of how hard estimating is psychologically. Even though these numbers are quite clear, I still think "that can't be right". It seems like I'm making good progress. Yeah, there's lots left to do, but 8 months seems like such a long time. Then again, it's already been a month and a half and it feels like I just started yesterday.
This is when I start to rationalize/justify the lower (quicker) estimate that I want to hear. After all, at the start I was learning a new language and new IDE. And I had a lot of questions to figure out in terms of how I was going to handle the conversion. Once I get up to speed it should go faster, right? Well, maybe, but then again, things can slow down too, when you hit a snag or when you've got a million finishing touches to do.
Part of the problem is that it's much easier to maintain motivation and drive for a short period. Once a project extends as long as a year it's a lot tougher to keep up the momentum, and a lot easier to get distracted (like with replication!). However, the nagging issues with the current Suneido and the business drive towards larger clients will continue to provide motivation!