Re: Generic generics help
On Aug 29, 12:11 am, "wizard of oz" <nos...@gtajb.com> wrote:
My first step is that in my add method, I need to ensure that my row and
column keys are in my list. I would like to use one common routine for th=
is.
The problem is I can't figure out the right generics syntax.
I think you need to do something like this (untested code). BTW, why
iterate through the set? The contains() method is meant to be used
for membership testing.
private <K> void ensureExists (TreeSet<K> treeSet, K key) {
if ( !treeSet.contains( key ))
treeSet.add( key );
}
Honestly, since a set is guaranteed to not have duplicate items, you
don't need the ensureExists() method at all. You could write your add
method as:
private Map<R, Map<C, E>> sparseMap = new HashMap<R, Map<C, E>>();
public void add (R rowKey, C colKey, E element) {
if ( !sparseMap.containsKey( rowKey ))
sparseMap.put( rowKey, new HashMap<C, E>() );
sparseMap.get( rowKey ).put( colKey, element );
}
-Lucas