org.modeshape.jcr.query.optimize
Class CopyCriteria

java.lang.Object
  org.modeshape.jcr.query.optimize.CopyCriteria

All Implemented Interfaces:

OptimizerRule

@Immutable
public class CopyCriteria
extends Object
implements OptimizerRule

An optimizer rule that copies SELECT nodes that apply to one side of a equi-join condition so that they also apply to the other side fo the equi-join condition.

Field Summary

static CopyCriteria

INSTANCE

Constructor Summary

CopyCriteria()

Method Summary

protected PlanNode	copySelectNode(QueryContext context, PlanNode selectNode, SelectorName selectorName, String propertyName, SelectorName copySelectorName, String copyPropertyName)
protected void	copySelectNodes(QueryContext context, PlanNode fromJoined, PlanNode toJoined)
PlanNode	execute(QueryContext context, PlanNode plan, LinkedList<OptimizerRule> ruleStack) Optimize the supplied plan using the supplied context, hints, and yet-to-be-run rules.
static Set<Column>	getColumnsReferencedBy(Visitable visitable) Get the set of Column objects that represent those columns referenced by the visitable object.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final CopyCriteria INSTANCE

Constructor Detail

CopyCriteria

public CopyCriteria()

Method Detail

execute

public PlanNode execute(QueryContext context,
                        PlanNode plan,
                        LinkedList<OptimizerRule> ruleStack)

Description copied from interface: OptimizerRule

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 null

plan - the plan to be optimized; never null

ruleStack - the stack of rules that will be run after this rule; never null

Returns:

the optimized plan; never null

copySelectNodes

protected void copySelectNodes(QueryContext context,
                               PlanNode fromJoined,
                               PlanNode toJoined)

copySelectNode

protected PlanNode copySelectNode(QueryContext context,
                                  PlanNode selectNode,
                                  SelectorName selectorName,
                                  String propertyName,
                                  SelectorName copySelectorName,
                                  String copyPropertyName)

toString

public String toString()

Overrides:

toString in class Object

getColumnsReferencedBy

public static Set<Column> getColumnsReferencedBy(Visitable visitable)

Get the set of Column objects that represent those columns referenced by the visitable object.

Parameters:

visitable - the object to be visited

Returns:

the set of Column objects, with column names that always are the string-form of the property name; never null