org.cloudgraph.hbase.scan

Class ScanRecognizerSyntaxTreeAssembler

java.lang.Object

org.plasma.query.visitor.DefaultQueryVisitor

org.cloudgraph.query.expr.ExpresionVisitorSupport

org.cloudgraph.query.expr.DefaultBinaryExprTreeAssembler

org.cloudgraph.hbase.scan.ScanRecognizerSyntaxTreeAssembler

All Implemented Interfaces:

ExprAssembler, org.plasma.query.visitor.QueryVisitor

public class ScanRecognizerSyntaxTreeAssembler
extends DefaultBinaryExprTreeAssembler

A binary expression tree assembler which constructs an operator precedence map, then visits (traverses) the given predicate expression syntax tree depth-first using an adapted shunting-yard algorithm and assembles a resulting binary tree structure with expression nodes specific for detecting i.e. recognizing one or more partial, fuzzy and other and other scan constructs. These are collected within the specific evaluation context passed to the assembled syntax tree.

The adapted shunting-yard algorithm in general uses a stack of operators and operands, and as new binary tree nodes are detected and created they are pushed onto the operand stack based on operator precedence. The resulting binary expression tree reflects the syntax of the underlying query expression including the precedence of its operators.

Since:

0.5.3

Author:

Scott Cinnamond

See Also:

ExprAssembler, DefaultBinaryExprTreeAssembler, ScanRecognizerContext

Field Summary

Fields

Modifier and Type	Field and Description
protected DataGraphMapping	graphConfig
protected StoreMappingContext	mappingContext

Fields inherited from class org.cloudgraph.query.expr.DefaultBinaryExprTreeAssembler

contextExpression, contextProperty, contextQueryProperty, contextType, predicates, rootType

Constructor Summary

Constructors

Constructor and Description
ScanRecognizerSyntaxTreeAssembler(org.plasma.query.model.Where predicate, org.plasma.sdo.PlasmaType rootType, StoreMappingContext mappingContext) Constructs an assembler based on the given predicate data graph configuration and graph root type.

Method Summary

Modifier and Type	Method and Description
LogicalBinaryExpr	createLogicalBinaryExpr(Expr left, Expr right, org.plasma.query.model.LogicalOperator operator) Creates and returns a logical binary expression based on the given terms and logical operator.
RelationalBinaryExpr	createRelationalBinaryExpr(org.plasma.query.model.Property property, org.plasma.query.model.Literal literal, org.plasma.query.model.RelationalOperator operator) Creates and returns a relational binary expression based on the given terms and relational operator.

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

createPredicateBinaryExpr, end, end, getResult, log, serialize, traverse

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, getContext, start, start, start, start, start, start, start, start, 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

Field Detail

graphConfig

protected DataGraphMapping graphConfig

mappingContext

protected StoreMappingContext mappingContext

Constructor Detail

ScanRecognizerSyntaxTreeAssembler

public ScanRecognizerSyntaxTreeAssembler(org.plasma.query.model.Where predicate,
                                         org.plasma.sdo.PlasmaType rootType,
                                         StoreMappingContext mappingContext)

Constructs an assembler based on the given predicate data graph configuration and graph root type.

Parameters:

predicate - the predicate

rootType - the graph root type

Method Detail

createRelationalBinaryExpr

public RelationalBinaryExpr createRelationalBinaryExpr(org.plasma.query.model.Property property,
                                                       org.plasma.query.model.Literal literal,
                                                       org.plasma.query.model.RelationalOperator operator)

Creates and returns a relational binary expression based on the given terms and relational operator.

Specified by:

createRelationalBinaryExpr in interface ExprAssembler

Overrides:

createRelationalBinaryExpr in class DefaultBinaryExprTreeAssembler

Parameters:

property - the property term

literal - the literal term

operator - the relational operator

Returns:

a relational binary expression based on the given terms and relational operator.

createLogicalBinaryExpr

public LogicalBinaryExpr createLogicalBinaryExpr(Expr left,
                                                 Expr right,
                                                 org.plasma.query.model.LogicalOperator operator)

Creates and returns a logical binary expression based on the given terms and logical operator.

Specified by:

createLogicalBinaryExpr in interface ExprAssembler

Overrides:

createLogicalBinaryExpr in class DefaultBinaryExprTreeAssembler

Parameters:

property - the property term

literal - the literal term

operator - the logical operator

Returns:

a wildcard binary expression based on the given terms and logical operator.