[jira] Commented: (LUCENE-1369) Eliminate unnecessary uses of Hashtable and Vector

["Michael McCandless (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/LUCENE-1369?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12628306#action_12628306 ] 

Michael McCandless commented on LUCENE-1369:
--------------------------------------------

This patch looks good, thanks DM!

The only issue I had was the addition of "implements PrecedenceQueryParserConstants" in PrecedenceQueryParser.jj:

{code}
  public class PrecedenceQueryParser implements PrecedenceQueryParserConstants {
{code}

When I ran javacc 3.2, which apparently also inserts its own "implements PrecedenceQueryParserConstants", it failed to compile.

I plan to commit in a day or two.

> Eliminate unnecessary uses of Hashtable and Vector
> --------------------------------------------------
>
>                 Key: LUCENE-1369
>                 URL: https://issues.apache.org/jira/browse/LUCENE-1369
>             Project: Lucene - Java
>          Issue Type: Improvement
>    Affects Versions: 2.3.2
>            Reporter: DM Smith
>            Assignee: Michael McCandless
>            Priority: Minor
>             Fix For: 2.4
>
>         Attachments: LUCENE-1369.patch
>
>
> Lucene uses Vector, Hashtable and Enumeration when it doesn't need to. Changing to ArrayList and HashMap may provide better performance.
> There are a few places Vector shows up in the API. IMHO, List should have been used for parameters and return values.
> There are a few distinct usages of these classes:
> # internal but with ArrayList or HashMap would do as well. These can simply be replaced.
> # internal and synchronization is required. Either leave as is or use a collections synchronization wrapper.
> # As a parameter to a method where List or Map would do as well. For contrib, just replace. For core, deprecate current and add new method signature.
> # Generated by JavaCC. (All *.jj files.) Nothing to be done here.
> # As a base class. Not sure what to do here. (Only applies to SegmentInfos extends Vector, but it is not used in a safe manner in all places. Perhaps, implements List would be better.)
> # As a return value from a package protected method, but synchronization is not used. Change return type.
> # As a return value to a final method. Change to List or Map.
> In using a Vector the following iteration pattern is frequently used.
> for (int i = 0; i < v.size(); i++) {
>   Object o = v.elementAt(i);
> }
> This is an indication that synchronization is unimportant. The list could change during iteration.

-- 
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-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-dev-help@lucene.apache.org