net.sf.farrago.fennel.rel
Class FennelAggRule

java.lang.Object
  extended by org.eigenbase.relopt.RelOptRule
      extended by net.sf.farrago.fennel.rel.FennelAggRule

public class FennelAggRule
extends RelOptRule

FennelAggRule is a rule for transforming AggregateRel to FennelAggRel.

Version:
$Id: //open/dev/farrago/src/net/sf/farrago/fennel/rel/FennelAggRule.java#3 $
Author:
John V. Sichi

Field Summary
static FennelAggRule instance
           
 
Fields inherited from class org.eigenbase.relopt.RelOptRule
ANY, description, operands
 
Constructor Summary
private FennelAggRule()
          Creates a FennelAggRule.
 
Method Summary
 CallingConvention getOutConvention()
          Returns the calling convention of the result of firing this rule, null if not known.
 void onMatch(RelOptRuleCall call)
          Receives notification about a rule match.
 
Methods inherited from class org.eigenbase.relopt.RelOptRule
convert, equals, equals, getOperand, getOperands, getOutTrait, hashCode, matches, mergeTraitsAndConvert, mergeTraitsAndConvert, toString
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

instance

public static final FennelAggRule instance
Constructor Detail

FennelAggRule

private FennelAggRule()
Creates a FennelAggRule.

Method Detail

getOutConvention

public CallingConvention getOutConvention()
Description copied from class: RelOptRule
Returns the calling convention of the result of firing this rule, null if not known.

Overrides:
getOutConvention in class RelOptRule

onMatch

public void onMatch(RelOptRuleCall call)
Description copied from class: RelOptRule
Receives notification about a rule match. At the time that this method is called, call.rels holds the set of relational expressions which match the operands to the rule; call.rels[0] is the root expression.

Typically a rule would check that the nodes are valid matches, creates a new expression, then calls back RelOptRuleCall.transformTo(org.eigenbase.rel.RelNode) to register the expression.

Specified by:
onMatch in class RelOptRule
Parameters:
call - Rule call
See Also:
RelOptRule.matches(RelOptRuleCall)