org.modeshape.jcr.query.process
Class SetOperationComponent

java.lang.Object
  org.modeshape.jcr.query.process.ProcessingComponent
      org.modeshape.jcr.query.process.SetOperationComponent

Direct Known Subclasses:

ExceptComponent, IntersectComponent, UnionComponent

public abstract class SetOperationComponent
extends ProcessingComponent

Nested Class Summary

Nested classes/interfaces inherited from class org.modeshape.jcr.query.process.ProcessingComponent

ProcessingComponent.DynamicOperation

Field Summary

protected Comparator<Object[]>

removeDuplicatesComparator

Constructor Summary

protected

SetOperationComponent(QueryContext context, QueryResults.Columns columns, Iterable<ProcessingComponent> sources, boolean alreadySorted, boolean all)

Method Summary

QueryResults.Columns	getColumns() Get the column definitions.
protected void	removeDuplicatesIfRequested(List<Object[]> tuples)
protected Iterable<ProcessingComponent>	sources()
protected static boolean	unionCompatible(QueryResults.Columns columns, Iterable<ProcessingComponent> sources)
protected static Iterable<ProcessingComponent>	wrapWithLocationOrdering(Iterable<ProcessingComponent> sources, boolean alreadySorted) The sources' results must be sorted before the intersection can be computed.

Methods inherited from class org.modeshape.jcr.query.process.ProcessingComponent

close, createDynamicOperation, createSortComparator, emptyTuples, execute, getContext, problems

Methods inherited from class java.lang.Object

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

Field Detail

removeDuplicatesComparator

protected final Comparator<Object[]> removeDuplicatesComparator

Constructor Detail

SetOperationComponent

protected SetOperationComponent(QueryContext context,
                                QueryResults.Columns columns,
                                Iterable<ProcessingComponent> sources,
                                boolean alreadySorted,
                                boolean all)

Method Detail

unionCompatible

protected static boolean unionCompatible(QueryResults.Columns columns,
                                         Iterable<ProcessingComponent> sources)

getColumns

public QueryResults.Columns getColumns()

Description copied from class: ProcessingComponent

Get the column definitions.

Overrides:

getColumns in class ProcessingComponent

Returns:

the column mappings; never null

sources

protected Iterable<ProcessingComponent> sources()

Returns:

sources

wrapWithLocationOrdering

protected static Iterable<ProcessingComponent> wrapWithLocationOrdering(Iterable<ProcessingComponent> sources,
                                                                        boolean alreadySorted)

The sources' results must be sorted before the intersection can be computed. Ensure that the sources' results are indeed sorted, and if not wrap them in a sorting component.

Parameters:

sources - the sources being intersected; may not be null

alreadySorted - true if the sources' results are already sorted, or false if they must be sorted by this component

Returns:

the sources (or their wrappers); never null

removeDuplicatesIfRequested

protected void removeDuplicatesIfRequested(List<Object[]> tuples)