This is a performance summary of 2 implementations of Element interface in AXIOM. One implementation uses java.util.ArrayList to hold child elements while the other keeps pointers to the first child and next/previous sibling in each element-- thus burning in the linked list into Element class itself. The latter as you know is what is used in AXIOM at the moment. However, recently there have been some discussion as to whether that is the right way to go...

Each row in the table below shows one set of test results. Each test comprised of first creating an Element, then adding a number of child elements and finally traversing all the child elements added. The number of child elements added and the number of traversals performed have been varied. Two approaches were used for traversing the children when using an ArrayList. One used an Iterator while the other used a 'for' loop. The details can be found by inspecting the code (ALElement, LLElement).

Have a look at the Tester for info on how the test was carried out.