[
https://issues.apache.org/jira/browse/LUCENE-2339?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12848591#action_12848591
]
Uwe Schindler edited comment on LUCENE-2339 at 3/23/10 7:17 AM:
----------------------------------------------------------------
bq. I just wanted to avoid converting arrays to a Collection, just so that they
can be iterated on.
Sorry, for the dumb question: In which JDK do arrays implement Iterable? From
my knowledge and a quick check with Java 5, it does not. Passing an array to a
method taking Iterable does not work. Arrays only work in extended for
statement, but not because they are Itearble. The generated code by javac is
also totally different (and more effective than creating an iterator, it just
uses the conventional for(i=0; i<length; i++) approach - try it out with javac
and decompiling with jad or whatever)! Also arrays of native types can hardly
implement Iterable without autoboxing.
See:
-
[http://stackoverflow.com/questions/1160081/why-is-an-array-not-assignable-to-iterable]
- [http://72.5.124.102/thread.jspa?threadID=558036&tstart=607]
And where is the waste of calling Arrays.asList()? This is exactly the same
overhead like creating an iterator() if arrays were Iterable, both are just
"views" on the array, so no copy involved.
was (Author: thetaphi):
bq. I just wanted to avoid converting arrays to a Collection, just so that
they can be iterated on.
Sorry, for the dumb question: In which JDK do arrays implement Iterable? From
my knowledge and a quick check with Java 5, it does not. Passing an array to a
method taking Iterable does not work. Arrays only work in extended for
statement, but not because they are Itearble. The generated code by javac is
also totally different (and more effective than creating an iterator, it just
uses the conventional for(i=0; i<length; i++) approach - try it out with javac
and decompiling with jad or whatever)! Also arrays of native types can hardly
implement Iterable without autoboxing.
See:
-
[http://stackoverflow.com/questions/1160081/why-is-an-array-not-assignable-to-iterable]
- [http://72.5.124.102/thread.jspa?threadID=558036&tstart=607]
> Allow Directory.copy() to accept a collection of file names to be copied
> ------------------------------------------------------------------------
>
> Key: LUCENE-2339
> URL: https://issues.apache.org/jira/browse/LUCENE-2339
> Project: Lucene - Java
> Issue Type: Improvement
> Reporter: Earwin Burrfoot
> Assignee: Michael McCandless
> Attachments: LUCENE-2339.patch, LUCENE-2339.patch, LUCENE-2339.patch
>
>
> Par example, I want to copy files pertaining to a certain commit, and not
> everything there is in a Directory.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: java-dev-h...@lucene.apache.org
