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Codemods for fixing common errors across many Java projects
The newest version!
This change updates new array creation with [Collection#toArray(T[])](https://docs.oracle.com/javase/8/docs/api/java/util/Collection.html#toArray-T:A-) to use an empty array argument, which is better for performance.
The point of the argument is provide an array to hold the objects and be returned, according to the documentation:
> If the collection fits in the specified array, it is returned therein.
Although it's not intuitive, allocating a right-sized array ahead of time to pass to the API appears to be [generally worse for performance](https://shipilev.net/blog/2016/arrays-wisdom-ancients/#_conclusion) according to benchmarking and JVM developers due to a number of implementation details in both Java and the virtual machine.
For a real world example, consider [this issue in H2](https://github.com/h2database/h2database/issues/311) where significant gains were achieved by switching to an empty array instead of a right-sized one.
Our changes look something like this:
```diff
- int[] tokenArray = tokens.toArray(new int[tokens.size()]);
+ int[] tokenArray = tokens.toArray(new int[0]);
processTokens(tokenArray);
```