On Jun 13, 2013, at 8:42 AM, Peter Levart <peter.lev...@gmail.com> wrote:
> On 06/13/2013 01:14 AM, Mike Duigou wrote: >> On Jun 12 2013, at 15:49 , Remi Forax wrote: >> >>> On 06/12/2013 11:23 PM, Mike Duigou wrote: >>>> Hello all; >>>> >>>> This patch adds optimized implementations of Map.forEach and >>>> Map.replaceAll to HashMap, Hashtable, IdentityHashMap, WeakHashMap, TreeMap >>>> >>>> http://cr.openjdk.java.net/~mduigou/JDK-8016446/0/webrev/ >>>> >>>> The implementations traverse the map more efficiently than the default >>>> iterator implementation and sometimes avoid creation of transient >>>> Map.Entry instances. The fast-fail behaviour of the default implementation >>>> is retained. >>>> >>>> Mike >>> Hi Mike, >>> funnily I was writing HashMap.forEach/LinkedHashMap.forEach at the same >>> time. >>> (you need also to override forEach in LinkedHashMap because the one you >>> inherits from HashMap doesn't use the linked list of entries). >> I don't think we need to offer a guarantee of ordering for the forEach but >> using the linked list is probably more efficient. > > The javadoc for Map.forEach says differently: > > default void forEach(BiConsumer > <http://download.java.net/jdk8/docs/api/java/util/function/BiConsumer.html><? > superK <http://download.java.net/jdk8/docs/api/java/util/Map.html>,? superV > <http://download.java.net/jdk8/docs/api/java/util/Map.html>> action) > > Performs the given action on each entry in this map, in the order entries are > returned by an entry set iterator (which may be unspecified) Right, LinkedHashMap should preserve the encounter order on traversal, bulk or otherwise. Note that there is a bug logged against LinkedHashMap.spliterator. It should but currently does not report ORDERED for key/value/entry Spliterators. Paul.
