[
https://issues.apache.org/jira/browse/CALCITE-1166?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16759504#comment-16759504
]
Julian Hyde commented on CALCITE-1166:
--------------------------------------
The OperandBuilder approach looks promising.
One slight change: rather than passing the root operand into the RelOptRule
constructor, pass the builder, and let the RelOptRuleConstructor call
{{build()}}. It's really useful for operands to be immutable AND know the rule
instance that they belong to (and their ordinal in the rule).
I don't feel strongly about this, but I don't think you need {{inputs}}. A
sequence of calls to {{input}} would probably be fine.
> Disallow sub-classes of RelOptRuleOperand
> -----------------------------------------
>
> Key: CALCITE-1166
> URL: https://issues.apache.org/jira/browse/CALCITE-1166
> Project: Calcite
> Issue Type: Bug
> Reporter: Julian Hyde
> Assignee: Julian Hyde
> Priority: Major
> Fix For: 1.8.0
>
>
> Disallow sub-classes of {{RelOptRuleOperand}}. The only reason that people
> have sub-classed {{RelOptRuleOperand}} is to override the {{boolean
> matches(RelNode)}} method, and you can now achieve that by supplying a
> {{Predicate}} to the constructor.
> Next release, we will deprecate {{RelOptRuleOperand}}'s protected constructor
> and create a new private or package-protected one. Later we will remove that
> constructor.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
