[jdom-interest] Announce: JDOMPlus a flexible XML framework for Java

Jason Hunter jhunter at collab.net
Wed Dec 6 11:14:47 PST 2000


> Java 2 Collections implement read only collections via alternate
> implementations of the collections interfaces. There are singleton
> immutable collections:-
> 
>     Collections.EMPTY_LIST;
>     Collections.EMPTY_MAP;
>     Collections.EMPTY_SET;
> 
> Each of these use private implementations of List, Map and Set 
> which fully implement their respective interfaces, they just throw
> UnsupportedOperationException when someone attempts to change their
> value.

Those aren't the classes that implement the unmodifiable behavior.  You
should look at UnmodifiableList in Collections.java.

-jh-



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