commons-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Bruno P. Kinoshita (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (COLLECTIONS-602) Improve efficiency of DefaultedMap.get
Date Fri, 19 May 2017 23:44:04 GMT

     [ https://issues.apache.org/jira/browse/COLLECTIONS-602?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Bruno P. Kinoshita updated COLLECTIONS-602:
-------------------------------------------
    Labels: help-wanted  (was: )

> Improve efficiency of DefaultedMap.get
> --------------------------------------
>
>                 Key: COLLECTIONS-602
>                 URL: https://issues.apache.org/jira/browse/COLLECTIONS-602
>             Project: Commons Collections
>          Issue Type: Bug
>            Reporter: John Mark
>              Labels: help-wanted
>
> The current implementation of {{org.apache.commons.collections4.map.DefaultedMap.get()}}
is inefficient since it always require two map lookups. There is no need to check map.containsKey()
every time. I would suggest implementing this method similar to the way that Java 8 does with
{{Map.getOrDefault()}}. My proposed implementation would be something like this:
> {code}
> public V get(final Object key) {
>     V v;
>     return ((v = map.get(key) != null) || map.containsKey(key)) ? v : value.transform((K)
key);
> }
> {code}
> It can be further optimized to not even call map.containsKey() if map is known to not
contain null values.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)

Mime
View raw message