org.eclipse.incquery.runtime.matchers.backend

Class QueryEvaluationHint

java.lang.Object

org.eclipse.incquery.runtime.matchers.backend.QueryEvaluationHint

public class QueryEvaluationHint
extends java.lang.Object

Provides IncQuery with additional hints on how a query should be evaluated. The same hint can be provided to multiple queries.

Here be dragons: for advanced users only.

Author:

Bergmann Gabor

Constructor Summary

Constructors

Constructor and Description
QueryEvaluationHint(java.lang.Class<? extends IQueryBackend> queryBackendClass, java.util.Map<java.lang.String,java.lang.Object> backendHints) Specifies the suggested query backend, and additional backend-specific options.

Method Summary

Modifier and Type	Method and Description
java.util.Map<java.lang.String,java.lang.Object>	getBackendHints() Each entry in the map overrides backend-specific options regarding query evaluation.
java.lang.Class<? extends IQueryBackend>	getQueryBackendClass() A suggestion for the query evaluator algorithm (whose factory must be registered).

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryEvaluationHint

public QueryEvaluationHint(java.lang.Class<? extends IQueryBackend> queryBackendClass,
                           java.util.Map<java.lang.String,java.lang.Object> backendHints)

Specifies the suggested query backend, and additional backend-specific options. Both parameters are optional.

Parameters:

queryBackendClass - overrides the query evaluator algorithm (whose factory must be registered); passing null retains the default algorithm associated with the query

backendHints - each entry in the map overrides backend-specific options regarding query evaluation (null-valued map entries permitted to erase hints); passing null means default options associated with the query

Method Detail

getQueryBackendClass

public java.lang.Class<? extends IQueryBackend> getQueryBackendClass()

A suggestion for the query evaluator algorithm (whose factory must be registered).

Can be null.

getBackendHints

public java.util.Map<java.lang.String,java.lang.Object> getBackendHints()

Each entry in the map overrides backend-specific options regarding query evaluation.

Can be null. Null-valued map entries permitted to erase hints.