org.cumulus4j.store.query.eval
Class LiteralEvaluator

java.lang.Object
  org.cumulus4j.store.query.eval.AbstractExpressionEvaluator<Literal>
      org.cumulus4j.store.query.eval.LiteralEvaluator

public class LiteralEvaluator
extends AbstractExpressionEvaluator<Literal>

Evaluator representing literals.

Author:

Marco หงุ่ยตระกูล-Schulze - marco at nightlabs dot de

Constructor Summary

LiteralEvaluator(QueryEvaluator queryEvaluator, AbstractExpressionEvaluator<?> parent, Literal expression)

Method Summary

protected Set<Long>	_queryResultDataEntryIDs(ResultDescriptor resultDescriptor) Execute a query for the given resultDescriptor.
Object	getLiteralValue()

Methods inherited from class org.cumulus4j.store.query.eval.AbstractExpressionEvaluator

_getResultSymbols, _queryResultObjects, getExpression, getFieldType, getLeft, getParent, getQueryEvaluator, getResultSymbols, getRight, queryResultDataEntryIDs, queryResultObjects, setLeft, setRight

Methods inherited from class java.lang.Object

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

Constructor Detail

LiteralEvaluator

public LiteralEvaluator(QueryEvaluator queryEvaluator,
                        AbstractExpressionEvaluator<?> parent,
                        Literal expression)

Method Detail

_queryResultDataEntryIDs

protected Set<Long> _queryResultDataEntryIDs(ResultDescriptor resultDescriptor)

Description copied from class: AbstractExpressionEvaluator

Execute a query for the given resultDescriptor. This method should contain the concrete logic for AbstractExpressionEvaluator.queryResultDataEntryIDs(ResultDescriptor) and must be implemented by subclasses.

Specified by:

_queryResultDataEntryIDs in class AbstractExpressionEvaluator<Literal>

Parameters:

resultDescriptor - the descriptor specifying what candidates (usually "this" or a variable) the caller is interested in as well as modifiers (e.g. negation) affecting the query.

Returns:

those dataEntryIDs that match the query criteria for the specified resultSymbol or null, if the symbol is not supported (this should be consistent with the implementation of AbstractExpressionEvaluator._getResultSymbols()).

See Also:

AbstractExpressionEvaluator.queryResultDataEntryIDs(ResultDescriptor)

getLiteralValue

public Object getLiteralValue()