org.eigenbase.relopt.volcano
Class RuleQueue.RuleMatchImportanceComparator

java.lang.Object
  org.eigenbase.relopt.volcano.RuleQueue.RuleMatchImportanceComparator

All Implemented Interfaces:

Comparator<VolcanoRuleMatch>

Enclosing class:

RuleQueue

private class RuleQueue.RuleMatchImportanceComparator
extends Object
implements Comparator<VolcanoRuleMatch>

Compares VolcanoRuleMatch objects according to their importance. Matches which are more important collate earlier. Ties are adjudicated by comparing the ids of the relational expressions matched.

Constructor Summary

private

RuleQueue.RuleMatchImportanceComparator()

Method Summary

int	compare(VolcanoRuleMatch match1, VolcanoRuleMatch match2)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Comparator

equals

Constructor Detail

RuleQueue.RuleMatchImportanceComparator

private RuleQueue.RuleMatchImportanceComparator()

Method Detail

compare

public int compare(VolcanoRuleMatch match1,
                   VolcanoRuleMatch match2)

Specified by:

compare in interface Comparator<VolcanoRuleMatch>