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• Final variables & fields are preferred where possible, but a lot of the code is old. Feel free to add them and hand the code back.
• If you have any skills with code coverage tools, then you'll probably find way too much to do! Tests are always welcome.
• There are over a 1,000 TODO comments in the code. Maybe some should be deleted. Maybe some could be completed. They probably all should have a JIRA id on them.
• Pick a random class, see if you can figure out what it is doing and javadoc it.
• Add @Override where applicable
• Intellij has an 'Inspect Code' feature. Yikes does it produce a lot of output.
• No doubt there is some exception handling that can be greatly improved.

Keep in mind people have to read and apply all these changes so resist the urge to fix everything everywhere and send huge patches. Fix a file or two and send it in as a patch and see what people think of the approach.

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Obviously, one could get quite bored doing just the above. But sometimes the above tasks can lead to more fun and exciting things. Anything that gets you in and looking at code and actually touching and changing it usually results in questions, discussions and ideas... then little passions and late nights and lack of sleep and caffeine abuse.

Things to avoid

Huge patches

Huge patches are hard to digest. Any step forward is a good one. Small steps allow people to see where you're headed and give input. Try to avoid them whenever possible. That's true regardless if you are a committer or contributor.

Be careful with reformatting

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