Efficient loop through Java List

Question

The following list is from the google I/O talk in 2008 called \"Dalvik Virtual Machine Internals\" its a list of ways to loop over a set of objects in order from most to least e

Answer 1

In case of Android, this is the video from Google Developers in 2015.

To Index or Iterate? (Android Performance Patterns Season 2 ep6) https://www.youtube.com/watch?v=MZOf3pOAM6A

They did the test on DALVIK runtime, 4.4.4 build, 10 times, to got average results. The result shows "For index" is the best.

int size = list.size();
for (int index = 0; index < size; index++) {
    Object object = list.get(index);
    ...
}

They also suggest to do similar test by yourself on your platform at the end of the video.