org.hibernate.engine.query.spi

Class QueryPlanCache

java.lang.Object

org.hibernate.engine.query.spi.QueryPlanCache

All Implemented Interfaces:

Serializable

public class QueryPlanCache
extends Object
implements Serializable

Acts as a cache for compiled query plans, as well as query-parameter metadata.

Author:

Steve Ebersole

See Also:

AvailableSettings.QUERY_PLAN_CACHE_PARAMETER_METADATA_MAX_SIZE, AvailableSettings.QUERY_PLAN_CACHE_MAX_SIZE, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_PARAMETER_METADATA_MAX_COUNT The default strong reference count.
static int	DEFAULT_QUERY_PLAN_MAX_COUNT The default soft reference count.

Constructor Summary

Constructors

Constructor and Description
QueryPlanCache(SessionFactoryImplementor factory) Constructs the QueryPlanCache to be used by the given SessionFactory

Method Summary

Modifier and Type	Method and Description
void	cleanup() Clean up the caches when the SessionFactory is closed.
FilterQueryPlan	getFilterQueryPlan(String filterString, String collectionRole, boolean shallow, Map<String,Filter> enabledFilters) Get the query plan for the given collection HQL filter fragment, creating it and caching it if not already cached
HQLQueryPlan	getHQLQueryPlan(String queryString, boolean shallow, Map<String,Filter> enabledFilters) Get the query plan for the given HQL query, creating it and caching it if not already cached
NativeQueryInterpreter	getNativeQueryInterpreter()
NativeSQLQueryPlan	getNativeSQLQueryPlan(NativeSQLQuerySpecification spec) Get the query plan for a native SQL query, creating it and caching it if not already cached
ParameterMetadata	getSQLParameterMetadata(String query, boolean isOrdinalParameterZeroBased) Obtain the parameter metadata for given native-sql query.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_PARAMETER_METADATA_MAX_COUNT

public static final int DEFAULT_PARAMETER_METADATA_MAX_COUNT

The default strong reference count.

See Also:

Constant Field Values

DEFAULT_QUERY_PLAN_MAX_COUNT

public static final int DEFAULT_QUERY_PLAN_MAX_COUNT

The default soft reference count.

See Also:

Constant Field Values

Constructor Detail

QueryPlanCache

public QueryPlanCache(SessionFactoryImplementor factory)

Constructs the QueryPlanCache to be used by the given SessionFactory

Parameters:

factory - The SessionFactory

Method Detail

getSQLParameterMetadata

public ParameterMetadata getSQLParameterMetadata(String query,
                                                 boolean isOrdinalParameterZeroBased)

Obtain the parameter metadata for given native-sql query.

for native-sql queries, the param metadata is determined outside any relation to a query plan, because query plan creation and/or retrieval for a native-sql query depends on all of the return types having been set, which might not be the case up-front when param metadata would be most useful

Parameters:

query - The query

Returns:

The parameter metadata

getHQLQueryPlan

public HQLQueryPlan getHQLQueryPlan(String queryString,
                                    boolean shallow,
                                    Map<String,Filter> enabledFilters)
                             throws QueryException,
                                    MappingException

Get the query plan for the given HQL query, creating it and caching it if not already cached

Parameters:

queryString - The HQL query string

shallow - Whether the execution will be shallow

enabledFilters - The filters enabled on the Session

Returns:

The query plan

Throws:

QueryException - Indicates a problem translating the query

MappingException - Indicates a problem translating the query

getFilterQueryPlan

public FilterQueryPlan getFilterQueryPlan(String filterString,
                                          String collectionRole,
                                          boolean shallow,
                                          Map<String,Filter> enabledFilters)
                                   throws QueryException,
                                          MappingException

Get the query plan for the given collection HQL filter fragment, creating it and caching it if not already cached

Parameters:

filterString - The HQL filter fragment

collectionRole - The collection being filtered

shallow - Whether the execution will be shallow

enabledFilters - The filters enabled on the Session

Returns:

The query plan

Throws:

QueryException - Indicates a problem translating the query

MappingException - Indicates a problem translating the query

getNativeSQLQueryPlan

public NativeSQLQueryPlan getNativeSQLQueryPlan(NativeSQLQuerySpecification spec)

Get the query plan for a native SQL query, creating it and caching it if not already cached

Parameters:

spec - The native SQL query specification

Returns:

The query plan

Throws:

QueryException - Indicates a problem translating the query

MappingException - Indicates a problem translating the query

cleanup

public void cleanup()

Clean up the caches when the SessionFactory is closed.

Note that depending on the cache strategy implementation chosen, clearing the cache might not reclaim all the memory.

Typically, when using LIRS, clearing the cache only invalidates the entries but the outdated entries are kept in memory until they are replaced by others. It is not considered a memory leak as the cache is bounded.

getNativeQueryInterpreter

public NativeQueryInterpreter getNativeQueryInterpreter()