Hi !
Featured games (90)
games approved by the League of Dukes
Games in Showcase (778)
Games in Android Showcase (231)
games submitted by our members
Games in WIP (856)
games currently in development
News: Read the Java Gaming Resources, or peek at the official Java tutorials
    Home     Help   Search   Login   Register   
Pages: [1]
  ignore  |  Print  
  Caches and guaranteed-order Hashtables etc - the e  (Read 2448 times)
0 Members and 1 Guest are viewing this topic.
Offline blahblahblahh

JGO Coder

Medals: 1

« Posted 2002-12-13 14:07:32 »

Real title: Caches and guaranteed-order Hashtables etc - the easy way (Sorry; this forum system sucks: short maximum topic-name length!).

Java now has support for very easy-to-make LRU-caches. It also provides a very simple way of making ANY Collection always iterate its contents in the same order (kind of ;). Yet another reason to upgrade to 1.4, I'm afraid ;).

I was developing with 1.4 for several months before I realised this had been added - it doesn't seem to have got much press alongside NBIO, regexp's, XML parsers, etc. Hence I thought I'd bring it to people's attention.

It's all provided by a new class within java.util.*: LinkedHashMap. The API docs have full instructions on how to use it in both ways; if you have any difficulty, let me know and I'll try and help (I frequently need caches for various things, and ditto with iteration-order-preservation, so I've used it quite a bit by this point).

malloc will be first against the wall when the revolution comes...
Offline leknor

Junior Devvie


« Reply #1 - Posted 2002-12-13 16:41:22 »

This is a little offtopic but I think ppl implementing a cache might find SoftReferences to be an useful alternative. For those that don't know a SoftReference is a link will break, provided certian requriements are met, and allow objects to be GCed instread of letting an OutOfMemoryException occur.

I wrote a web app where behind the scenes some heavy weight network connections we being made on a per user basis. I wanted to be able to cache and reuse these connections but also not have to worry about running out of memory. So I added SoftReferences between the network connections and my connection pool for each user. The code ran fine but the SoftReferences were breaking too soon. After doign a lot of searching I found that:

SoftReferences only work as desired when the -server flag is passed to the JVM. With the -client JVM a SoftReference is a lot like a WeakReference which isn't quite what I wanted. Hopefully any game server writers will find this useful.
Pages: [1]
  ignore  |  Print  

hadezbladez (358 views)
2018-11-16 13:46:03

hadezbladez (190 views)
2018-11-16 13:41:33

hadezbladez (361 views)
2018-11-16 13:35:35

hadezbladez (90 views)
2018-11-16 13:32:03

EgonOlsen (2190 views)
2018-06-10 19:43:48

EgonOlsen (2226 views)
2018-06-10 19:43:44

EgonOlsen (1384 views)
2018-06-10 19:43:20

DesertCoockie (2022 views)
2018-05-13 18:23:11

nelsongames (1674 views)
2018-04-24 18:15:36

nelsongames (2312 views)
2018-04-24 18:14:32
Deployment and Packaging
by mudlee
2018-08-22 18:09:50

Java Gaming Resources
by gouessej
2018-08-22 08:19:41

Deployment and Packaging
by gouessej
2018-08-22 08:04:08

Deployment and Packaging
by gouessej
2018-08-22 08:03:45

Deployment and Packaging
by philfrei
2018-08-20 02:33:38

Deployment and Packaging
by philfrei
2018-08-20 02:29:55

Deployment and Packaging
by philfrei
2018-08-19 23:56:20

Deployment and Packaging
by philfrei
2018-08-19 23:54:46 is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑
Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines | Managed by Enhanced Four Valid XHTML 1.0! Valid CSS!