Is it better to use System.arraycopy(…) than a for loop for copying arrays?

Question

I want to create a new array of objects putting together two smaller arrays.

They can\'t be null, but size may be 0.

I can\'t chose between these two ways: a

Answer 1

It depends on the virtual machine, but System.arraycopy should give you the closest you can get to native performance.

I've worked for 2 years as a java developer for embedded systems (where performance is a huge priority) and everywhere System.arraycopy could be used, I've mostly used it / seen it used in existing code. It's always preferred over loops when performance is an issue. If performance isn't a big issue, I'd go with the loop, though. Much easier to read.