org.cloudgraph.hbase.filter

Class PredicateColumnFilterAssembler

java.lang.Object

org.plasma.query.visitor.DefaultQueryVisitor

org.cloudgraph.query.expr.ExpresionVisitorSupport

org.cloudgraph.hbase.filter.FilterHierarchyAssembler

org.cloudgraph.hbase.filter.PredicateVisitor

org.cloudgraph.hbase.filter.ColumnPredicateVisitor

org.cloudgraph.hbase.filter.PredicateColumnFilterAssembler

All Implemented Interfaces:

Assembler, HBaseFilterAssembler, PredicateFilterAssembler, org.plasma.query.visitor.QueryVisitor

public class PredicateColumnFilterAssembler
extends ColumnPredicateVisitor
implements PredicateFilterAssembler

Creates an HBase column filter hierarchy to return HBase scan results representing part of a graph "slice" from the set of columns making up a collection or collection property within the graph. Uses QualifierFilter /ValueFilter pairs recreating composite column qualifier prefixes using CompositeColumnKeyFactory. Processes visitor events for query model elements specific to assembly of HBase column filters, such as properties, wildcards, literals, logical operators, relational operators, within the context of HBase filter hierarchy assembly. Maintains various context information useful to subclasses.

HBase filters may be collected into lists using FilterList each with a MUST_PASS_ALL or MUST_PASS_ONE (logical) operator. Lists may then be assembled into hierarchies used to represent complex expression trees filtering either rows or columns in HBase.

Since:

0.5

Author:

Scott Cinnamond

See Also:

key.CompositeColumnKeyFactory

Field Summary

Fields inherited from class org.cloudgraph.hbase.filter.ColumnPredicateVisitor

columnKeyFac, contextPropertyPath, contextQueryProperty, predicateUtil

Fields inherited from class org.cloudgraph.hbase.filter.PredicateVisitor

contextHBaseCompareOp, contextOpWildcard, contextProperty, contextType, contextWildcardOperator

Fields inherited from class org.cloudgraph.hbase.filter.FilterHierarchyAssembler

filterStack, params, rootFilter, rootType

Constructor Summary

Constructors

Constructor and Description
PredicateColumnFilterAssembler(org.plasma.sdo.PlasmaType rootType, StoreMappingContext mappingContext) Constructor which takes a query where clause containing any number of predicates and traverses these as a {org.plasma.query.visitor.QueryVisitor visitor} only processing various traversal events as needed against the given root type.

Method Summary

Modifier and Type	Method and Description
void	assemble(org.plasma.query.model.Where where, org.plasma.sdo.PlasmaType contextType) Assembles a predicate filter list or hierarchy based on one or more given query predicates.
void	clear()
protected void	log(org.plasma.query.model.Where root)

Methods inherited from class org.cloudgraph.hbase.filter.ColumnPredicateVisitor

end, start, start, start, start, start, start

Methods inherited from class org.cloudgraph.hbase.filter.PredicateVisitor

start, start

Methods inherited from class org.cloudgraph.hbase.filter.FilterHierarchyAssembler

filterTokens, getFilter, getParams, popFilter, pushFilter, pushFilter

Methods inherited from class org.cloudgraph.query.expr.ExpresionVisitorSupport

getChildExpressionCount, getChildExpressions, getLogicalOperatorCount, hasChildExpressions, hasWildcard

Methods inherited from class org.plasma.query.visitor.DefaultQueryVisitor

end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, end, getContext, start, start, start, start, start, start, start, start, start, start, start, start, start, start, start, start, start

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.cloudgraph.hbase.filter.HBaseFilterAssembler

getFilter

Constructor Detail

PredicateColumnFilterAssembler

public PredicateColumnFilterAssembler(org.plasma.sdo.PlasmaType rootType,
                                      StoreMappingContext mappingContext)

Constructor which takes a query where clause containing any number of predicates and traverses these as a {org.plasma.query.visitor.QueryVisitor visitor} only processing various traversal events as needed against the given root type.

Parameters:

where - where the where clause

contextType - the current SDO type

rootType - the graph root type

See Also:

QueryVisitor, Query

Method Detail

assemble

public void assemble(org.plasma.query.model.Where where,
                     org.plasma.sdo.PlasmaType contextType)

Description copied from interface: PredicateFilterAssembler

Assembles a predicate filter list or hierarchy based on one or more given query predicates.

Specified by:

assemble in interface PredicateFilterAssembler

Parameters:

where - the where clause

contextType - the context type which may be the root type or another type linked by one or more relations to the root

clear

public void clear()

Specified by:

clear in interface Assembler

Overrides:

clear in class PredicateVisitor

log

protected void log(org.plasma.query.model.Where root)

Overrides:

log in class FilterHierarchyAssembler