org.apache.cayenne.query

Class QueryMetadataProxy

java.lang.Object

org.apache.cayenne.query.QueryMetadataProxy

All Implemented Interfaces:

QueryMetadata

public class QueryMetadataProxy
extends Object
implements QueryMetadata

Since:

4.0

Field Summary

Fields

Modifier and Type	Field and Description
protected QueryMetadata	mdDelegate

Fields inherited from interface org.apache.cayenne.query.QueryMetadata

CACHE_GROUPS_PROPERTY, CACHE_STRATEGY_PROPERTY, FETCH_LIMIT_DEFAULT, FETCH_LIMIT_PROPERTY, FETCH_OFFSET_DEFAULT, FETCH_OFFSET_PROPERTY, FETCHING_DATA_ROWS_DEFAULT, FETCHING_DATA_ROWS_PROPERTY, PAGE_SIZE_DEFAULT, PAGE_SIZE_PROPERTY, STATEMENT_FETCH_SIZE_DEFAULT, STATEMENT_FETCH_SIZE_PROPERTY

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	QueryMetadataProxy(QueryMetadata mdDelegate)

Method Summary

Modifier and Type	Method and Description
String	getCacheGroup() Returns an optional cache "group".
String[]	getCacheGroups() Deprecated.
String	getCacheKey() Returns a String that uniquely identifies this query for the purposes of result caching.
QueryCacheStrategy	getCacheStrategy() Returns a caching strategy for this query.
ClassDescriptor	getClassDescriptor()
DataMap	getDataMap() Returns a DataMap associated with a query or null if no such DataMap exists.
DbEntity	getDbEntity() Returns a DbEntity associated with a query or null if no such entity exists.
int	getFetchLimit() Returns the limit on the maximum number of records that can be returned by this query.
int	getFetchOffset() Specifies a start of a range when fetching a subset of records.
ObjEntity	getObjEntity() Returns an ObjEntity associated with a query or null if no such entity exists.
Query	getOrginatingQuery() Deprecated.
Query	getOriginatingQuery() Returns a query that originated this query.
int	getPageSize() Returns query page size.
Map<String,String>	getPathSplitAliases() Returns a map of aliases vs.
PrefetchTreeNode	getPrefetchTree() Returns a root node of prefetch tree used by this query, or null of no prefetches are configured.
Procedure	getProcedure() Returns a Procedure associated with a query or null if no such procedure exists.
List<Object>	getResultSetMapping() Returns an optional list of result set mapping hints.
int	getStatementFetchSize()
boolean	isFetchingDataRows() Returns true if this query should produce a list of data rows as opposed to DataObjects, false for DataObjects.
boolean	isRefreshingObjects() Returns true if the query results should replace any currently cached values, returns false otherwise.
boolean	isSingleResultSetMapping()
boolean	isSuppressingDistinct()

Methods inherited from class java.lang.Object

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

Field Detail

mdDelegate

protected QueryMetadata mdDelegate

Constructor Detail

QueryMetadataProxy

protected QueryMetadataProxy(QueryMetadata mdDelegate)

Method Detail

getCacheGroups

@Deprecated
public String[] getCacheGroups()

Deprecated.

Description copied from interface: QueryMetadata

Returns an optional array of cache "groups". Cache groups allow to invalidate query caches in bulk on different events. Usually the first group in the array is considered to be the "main" group that is used for declarative cache invalidation with some cache providers.

Specified by:

getCacheGroups in interface QueryMetadata

See Also:

QueryMetadata.getCacheGroup()

getCacheGroup

public String getCacheGroup()

Description copied from interface: QueryMetadata

Returns an optional cache "group". Cache groups allow to invalidate query caches in bulk on different events.

Specified by:

getCacheGroup in interface QueryMetadata

getCacheKey

public String getCacheKey()

Description copied from interface: QueryMetadata

Returns a String that uniquely identifies this query for the purposes of result caching. If null is returned, no caching is performed.

Specified by:

getCacheKey in interface QueryMetadata

getCacheStrategy

public QueryCacheStrategy getCacheStrategy()

Description copied from interface: QueryMetadata

Returns a caching strategy for this query.

Specified by:

getCacheStrategy in interface QueryMetadata

getClassDescriptor

public ClassDescriptor getClassDescriptor()

Specified by:

getClassDescriptor in interface QueryMetadata

getDataMap

public DataMap getDataMap()

Description copied from interface: QueryMetadata

Returns a DataMap associated with a query or null if no such DataMap exists.

Specified by:

getDataMap in interface QueryMetadata

getDbEntity

public DbEntity getDbEntity()

Description copied from interface: QueryMetadata

Returns a DbEntity associated with a query or null if no such entity exists.

Specified by:

getDbEntity in interface QueryMetadata

getFetchLimit

public int getFetchLimit()

Description copied from interface: QueryMetadata

Returns the limit on the maximum number of records that can be returned by this query. If the actual number of rows in the result exceeds the fetch limit, they will be discarded. One possible use of fetch limit is using it as a safeguard against large result sets that may lead to the application running out of memory, etc. If a fetch limit is greater or equal to zero, all rows will be returned.

Specified by:

getFetchLimit in interface QueryMetadata

Returns:

the limit on the maximum number of records that can be returned by this query

getFetchOffset

public int getFetchOffset()

Description copied from interface: QueryMetadata

Specifies a start of a range when fetching a subset of records.

Specified by:

getFetchOffset in interface QueryMetadata

getObjEntity

public ObjEntity getObjEntity()

Description copied from interface: QueryMetadata

Returns an ObjEntity associated with a query or null if no such entity exists.

Specified by:

getObjEntity in interface QueryMetadata

getOrginatingQuery

@Deprecated
public Query getOrginatingQuery()

Deprecated.

Specified by:

getOrginatingQuery in interface QueryMetadata

getOriginatingQuery

public Query getOriginatingQuery()

Description copied from interface: QueryMetadata

Returns a query that originated this query. Originating query is a query whose result is needed to obtain the result of the query owning this metadata. Most often than not the returned value is null. One example of non-null originating query is a query for a range of objects in a previously fetched paginated list. The query that fetched the original paginated list is an "originated" query. It may be used to restore a list that got lost due to a cache overflow, etc.

Specified by:

getOriginatingQuery in interface QueryMetadata

getPageSize

public int getPageSize()

Description copied from interface: QueryMetadata

Returns query page size. Page size is a hint to Cayenne that query should be performed page by page, instead of retrieving all results at once. If the value returned is less than or equal to zero, no paging should occur.

Specified by:

getPageSize in interface QueryMetadata

getPrefetchTree

public PrefetchTreeNode getPrefetchTree()

Description copied from interface: QueryMetadata

Returns a root node of prefetch tree used by this query, or null of no prefetches are configured.

Specified by:

getPrefetchTree in interface QueryMetadata

getPathSplitAliases

public Map<String,String> getPathSplitAliases()

Description copied from interface: QueryMetadata

Returns a map of aliases vs. expression subpaths that is used to build split joins.

Specified by:

getPathSplitAliases in interface QueryMetadata

getProcedure

public Procedure getProcedure()

Description copied from interface: QueryMetadata

Returns a Procedure associated with a query or null if no such procedure exists.

Specified by:

getProcedure in interface QueryMetadata

getResultSetMapping

public List<Object> getResultSetMapping()

Description copied from interface: QueryMetadata

Returns an optional list of result set mapping hints. Elements in the list can be either EntityResultSegment or ScalarResultSegment. The returned list can be null.

Specified by:

getResultSetMapping in interface QueryMetadata

isSingleResultSetMapping

public boolean isSingleResultSetMapping()

Specified by:

isSingleResultSetMapping in interface QueryMetadata

Returns:

should the result be mapped to single object (scalar or entity)

See Also:

QueryMetadata.getResultSetMapping()

isFetchingDataRows

public boolean isFetchingDataRows()

Description copied from interface: QueryMetadata

Returns true if this query should produce a list of data rows as opposed to DataObjects, false for DataObjects. This is a hint to QueryEngine executing this query.

Specified by:

isFetchingDataRows in interface QueryMetadata

isRefreshingObjects

public boolean isRefreshingObjects()

Description copied from interface: QueryMetadata

Returns true if the query results should replace any currently cached values, returns false otherwise. If QueryMetadata.isFetchingDataRows() returns true, this setting is not applicable and has no effect.

Specified by:

isRefreshingObjects in interface QueryMetadata

getStatementFetchSize

public int getStatementFetchSize()

Specified by:

getStatementFetchSize in interface QueryMetadata

Returns:

statement's fetch size

isSuppressingDistinct

public boolean isSuppressingDistinct()

Specified by:

isSuppressingDistinct in interface QueryMetadata