That's quite likely. You are replacing low-level procedural code (loops etc) with higher-level declarative code. However, I think you would have to be processing a lot of data for any difference to be significant.
It gets a lot more interesting if you add one word..
now Java will use multiple threads to process parts of the data in parallel. Assuming you have multi-cpu hardware this can give you very significant gains, and the code is orders of magnitude easier than splitting it up and running loops in multiple threads yourself.