org.eclipse.incquery.runtime.matchers.backend

Interface IQueryBackend

All Known Implementing Classes:

LocalSearchBackend, ReteEngine

public interface IQueryBackend

Internal interface for an IncQuery query specification. Each query is associated with a pattern. Methods instantiate a matcher of the pattern with various parameters.

Since:

0.9

Author:

Bergmann Gábor

Method Summary

Modifier and Type	Method and Description
void	dispose() Disposes the query backend.
IQueryResultProvider	getResultProvider(PQuery query) Returns a result provider for a given query.
boolean	isCaching()
IQueryResultProvider	peekExistingResultProvider(PQuery query) Returns an existing result provider for a given query, if it was previously constructed, returns null otherwise.

Method Detail

isCaching

boolean isCaching()

Returns:

true iff this backend is incremental, i.e. it caches the results of queries for quick retrieval, and can provide update notifications on result set changes.

getResultProvider

IQueryResultProvider getResultProvider(PQuery query)
                                throws QueryProcessingException

Returns a result provider for a given query. Repeated calls may return the same instance.

Throws:

QueryProcessingException

peekExistingResultProvider

IQueryResultProvider peekExistingResultProvider(PQuery query)

Returns an existing result provider for a given query, if it was previously constructed, returns null otherwise. Will not construct and initialize new result providers.

dispose

void dispose()

Disposes the query backend.