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Message-ID: <49FEF7B4.2090306@gmail.com>
Date: Mon, 04 May 2009 16:12:04 +0200
From: Felix Meschberger <fmeschbe@gmail.com>
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To: dev@jackrabbit.apache.org
Subject: Re: Generics generator class
References: <91f3b2650905040617w57e838c8y106809810c6aaa82@mail.gmail.com>
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Hi,

Thomas M=FCller schrieb:
> Hi,
>=20
> I would like to use Java 1.5 features now in Jackrabbit. I hope this
> will improve reliability, simplify maintenance, and reduce source code
> size. Unfortunately using generics is sometimes quite verbose.

I don't consider this a big issue.

> Example:
>=20
> HashMap wspInfos =3D new HashMap();
> becomes
> HashMap<String, WorkspaceInfo> wspInfos =3D new HashMap<String, Workspa=
ceInfo>();
>=20
> Part of that could be avoided using a helper class:
>=20
> HashMap<String, WorkspaceInfo> wspInfos =3D New.hashMap();
>=20
> I propose to add a new 'generics generator class' called 'New' to
> jackrabbit-jcr-commons. It would contain constructor methods for the
> most commonly used collection objects.
>=20
> public class New {
>     public static <K, V> HashMap<K, V> hashMap() {
>         return new HashMap<K, V>();
>     }
>     public static <T> ArrayList<T> arrayList() {
>         return new ArrayList<T>();
>     }
>     public static <T> WeakReference<T> weakReference(T t) {
>         return new WeakReference<T>(t);
>     }
>     ...
> }
>=20
> What do you think? Are there better solutions?

-1

Starting to have such helper classes amounts to a spiral with no end.
There is IMHO also no use.

In fact, while the "new HashMap<String, WorkspaceInfo>()" construct has
almost no influence on the generated class file, the helper class
creates a new class object and increases memory footprint. I think the
price is beyond what might be acceptable.

Regards
Felix


>=20
> Regards,
> Thomas
>=20