Re: Re: Receiving the all the entries that belongs to a group

I have in my application a huge cache which cannot be keep it in
memory(arround 200MB). So I intended to use a cache with a small
memory size, and unlimited disk size. Also my entries should never
expire(are read-only persistent objects). I wanted to keep different
type of entries(I have around 25-50 types of objects that should be
cached) in different groups. The keys for entry are a specific prefix
for each group appended to the hash code of the object (which is
guaranted to be unique). For some types of entries, for which I load
all the required data at startup(other entries can be added also
during the application life time, but these entries are never
deleted) I have a business requirement, which asks me for all the
entries of that type. So it looks like I need to get all entries for
a group(both from memory and disk)- a statical snapshot with the
members of the group at a specific time. 

Assuming that it's ok for me to get a statical snapshot of a group, I
added to the Cache class the following methods:

public Object[] getGroupFromCache(String groupName, Class entryType) {
        Set groupEntries = cacheMap.getGroup(groupName);
        ArrayList result = new ArrayList();
        if (groupEntries != null) {            
            Iterator itr = groupEntries.iterator();            
            while (itr.hasNext()) {
                try {
    result.add(getFromCache((String) itr.next()));                    
                } catch (NeedsRefreshException ne) {
                    //just ignore this entry
                }
            }
        }
return result.toArray((Object[])
java.lang.reflect.Array.newInstance(entryType, result.size()));
    }

    public Object[] getGroupFromCache(String groupName) {
        return getGroupFromCache(groupName, Object.class);
    }
Is in your opinion, Chris this code ok? 

Regarding the performance of the OSCache(because I follow the
performence discussion about oscache form this mailing list), I have
big performance problems with my caching model. As I told you I need
a huge disk-based cache for my application. At my first test with
OSCache, I was tring to store each item of a big search in the
cache(there was thousands of items, with a total size of 35MB).
Without OSCache, the time for this serach was just around a minute.
When I was trying to store these entries with OSCache, the time jump
to more then 2 hours.  So it looks that the default persistent
listener is not suitable for such kind of scenarios...

Best Regards and Merrie Christmas!
Romulus
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