org.jboss.dna.graph.query.optimize
Class RemoveEmptyAccessNodes
java.lang.Object
org.jboss.dna.graph.query.optimize.RemoveEmptyAccessNodes
- All Implemented Interfaces:
- OptimizerRule
@Immutable
public class RemoveEmptyAccessNodes
- extends Object
- implements OptimizerRule
An optimizer rule
that removes any ACCESS nodes that are known to never return any tuples because of
conflicting constraints.
INSTANCE
public static final RemoveEmptyAccessNodes INSTANCE
RemoveEmptyAccessNodes
public RemoveEmptyAccessNodes()
execute
public PlanNode execute(QueryContext context,
PlanNode plan,
LinkedList<OptimizerRule> ruleStack)
- Optimize the supplied plan using the supplied context, hints, and yet-to-be-run rules.
- Specified by:
execute
in interface OptimizerRule
- Parameters:
context
- the context in which the query is being optimized; never nullplan
- the plan to be optimized; never nullruleStack
- the stack of rules that will be run after this rule; never null
- Returns:
- the optimized plan; never null
- See Also:
OptimizerRule.execute(org.jboss.dna.graph.query.QueryContext,
org.jboss.dna.graph.query.plan.PlanNode, java.util.LinkedList)
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