PDDocumentCatalog etc. Optimization ?

[Alan Thomas <ja...@verizon.net>]

        I was iterating over some pages in a PDDocument, and did it this 
way:

            List pages = document.getDocumentCatalog().getAllPages();
            for (Object obj : pages)
            {
                PDPage page = (PDPage)obj;

because the list returned by PDDocumentCatalog.getAllPages() is declared as 
an
ArrayList vice an ArrayList of PDPages (see below).  Thus, the extra type 
conversion
in every iteration.

    public List getAllPages()
    {
        List retval = new ArrayList();
        PDPageNode rootNode = getPages();
        //old (slower):
        //getPageObjects( rootNode, retval );
        rootNode.getAllKids(retval);
        return retval;
    }

       The Java 6 "for" loop is typically 25+% faster for iterating over a 
list than using a list iterator.
However, in this case, it made no difference (over 10-20 iterations and only 
looking at seconds).

       Would it be possible to do this sort of optimizations esp. on methods 
that return a list of pages?
I realize there may be many complications of which I am not aware.

Thanks, Alan