Re: Class I would like to commit to commons Collections

[Stephen Kestle]

Hi John, I have not opened a ticket yet, but ... I have had very similar requirements, and will [most-likely] be putting something in that will solve your problem. However, it will not be a class - consider this method Map<C, K,V> CollectionUtils.toMap(Collection<C> input, Transformer<C,K> keyTransformer, Transformer<C,V> valueTransformer, Map<K,V> map) You could then do what you wanted, passing in your integer transformer for the key, and potentially MultiHashMap for the map.  NB - this is in an ideal (and we're heading to that) collections world.  MultiHashMap will need to be changed to extend map properly and implement the interface in a consistent way (not breaking Map contract etc). Also note that there will be other variations on the method - most commonly Map<K,V> CollectionUtils.toMap(Collection<V> input, Transformer<V,K> keyTransformer){      return toMap(input, keyTransformer, NOPTransformer, new HashMap<K,V>()); } I'll raise a ticket within the next few days - watch this list! Cheers Stephen John wrote: Hi, I'm new to the collections mailing list and I have a class I think would be appropriate to be donated to the collections API. This is an extension of the MultiHashMap and filters a given Collection by a given field. It will put the objects into the map using the field value as the key. For example, lets say I have a class X which has an integer i. I have four instances of X each with the following names and values of i. x1 i=1 x2 i=2 x3 i=2 x4 i=5 The resulting MultiHashMap will contain the following after a call to sortCollection(X.class, "i"); has been made. key | Objects 1   | x1 2   | x2, x3 5   | x4 I can then get a Collection of sorted objects by asking the map for the key value. I find this very useful in many situations I have come across. I will of course make the required doc, package and src formatting changes to the class before submitting it. Please can you take a look and tell me if it is worth committing this to the Collections repository. What is the process I need to go through before committing? I'm a bit pressed for time at the mo' so I can't really spend too much time working on the Collections API as a regular developer. I am a big fan of the commons Collections API and commons project in general, just wish I had more time to get involved. Kind regards, John Hunsley. Technical Supervisor, Cy-nap Ltd. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] -- Stephen Kestle Software Engineer [EMAIL PROTECTED] P: +64 9 638 0619 M: +64 27 453 7853 F: +64 9 638 0699 S: skestle www.orionhealth.com This e-mail and any attachments are intended only for the person to whom it is addressed and may contain privileged, proprietary, or other data protected from disclosure under applicable law. If you are not the addressee or the person responsible for delivering this to the addressee you are hereby notified that reading, copying or distributing this transmission is prohibited. If you have received this e-mail in error, please telephone us immediately and remove all copies of it from your system. Thank you for your co-operation.