[
https://issues.apache.org/jira/browse/COLLECTIONS-536?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Thomas Neidhart resolved COLLECTIONS-536.
-----------------------------------------
Resolution: Fixed
Fix Version/s: 4.1
Fixed in r1635303.
Thanks for the report!
> (Code style) map.size() call in MapUtils.putAll()
> -------------------------------------------------
>
> Key: COLLECTIONS-536
> URL: https://issues.apache.org/jira/browse/COLLECTIONS-536
> Project: Commons Collections
> Issue Type: Bug
> Components: Map
> Affects Versions: 3.2.1, 4.0
> Environment: Any
> Reporter: Tagir Valeev
> Priority: Trivial
> Labels: performance
> Fix For: 4.1
>
>
> In class org.apache.commons.collections(4).MapUtils there's a method
> putAll(final Map<K, V> map, final Object[] array) which starts with
> {noformat}
> map.size(); // force NPE
> {noformat}
> Actually map.size() is not that harmless call for any map. For example,
> consider java.util.concurrent.ConcurrentHashMap size() implementation:
> depending on the circumstances it may take even more time than the rest of
> the putAll method (at least prior to JDK 8). Things are even worse for
> ConcurrentSkipListMap: its size() method iterates over all the map elements.
> Thus I'd suggest to replace this call with more conventional check like:
> {noformat}
> if(map == null) {
> throw new NullPointerException();
> }
> {noformat}
> If you still want to save bytes, you may use {{map.getClass()}}. It's final,
> so it will never be overridden to do something strange and it's even used by
> JavaC for the same purpose (to trigger NPE). For example, if you compile and
> disassemble this code:
> {noformat}
> public class Outer {
> public class Inner {}
> public void test(Outer n) { n.new Inner(); }
> }
> {noformat}
> You will see a getClass() call which is used to trigger NPE.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
