com.thinkaurelius.titan.graphdb.query

Interface TitanPredicate

All Superinterfaces:

com.tinkerpop.blueprints.Predicate

All Known Implementing Classes:

Cmp, Contain, Geo, Text

public interface TitanPredicate
extends com.tinkerpop.blueprints.Predicate

Titan's extension of Blueprint's Predicate interface. Contains some custom methods that Titan needs for query answering and evaluation.

This class contains a subclass used to convert Blueprint's Predicate to the corresponding Titan predicates.

Author:

Matthias Broecheler (me@matthiasb.com)

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	TitanPredicate.Converter

Method Summary

Methods

Modifier and Type	Method and Description
boolean	evaluate(Object value, Object condition)
boolean	hasNegation() Whether this predicate has a predicate that is semantically its negation.
boolean	isQNF() Returns true if this predicate is in query normal form.
boolean	isValidCondition(Object condition) Whether the given condition is a valid condition for this predicate.
boolean	isValidValueType(Class<?> clazz) Whether the given class is a valid data type for a value to which this predicate may be applied.
TitanPredicate	negate() Returns the negation of this predicate if it exists, otherwise an exception is thrown.

Method Detail

isValidCondition

boolean isValidCondition(Object condition)

Whether the given condition is a valid condition for this predicate.

For instance, the Cmp.GREATER_THAN would require that the condition is comparable and not null.

Parameters:

condition -

Returns:

isValidValueType

boolean isValidValueType(Class<?> clazz)

Whether the given class is a valid data type for a value to which this predicate may be applied.

For instance, the Cmp.GREATER_THAN can only be applied to Comparable values.

Parameters:

clazz -

Returns:

hasNegation

boolean hasNegation()

Whether this predicate has a predicate that is semantically its negation. For instance, Cmp.EQUAL and Cmp.NOT_EQUAL are negatives of each other.

Returns:

negate

TitanPredicate negate()

Returns the negation of this predicate if it exists, otherwise an exception is thrown. Check hasNegation() first.

Returns:

isQNF

boolean isQNF()

Returns true if this predicate is in query normal form.

Returns:

evaluate

boolean evaluate(Object value,
               Object condition)

Specified by:

evaluate in interface com.tinkerpop.blueprints.Predicate