org.neodatis.odb.core.query.execution

Class GenericQueryExecutor

java.lang.Object

org.neodatis.odb.core.query.execution.GenericQueryExecutor

All Implemented Interfaces:

IMultiClassQueryExecutor, IQueryExecutor

Direct Known Subclasses:

CriteriaQueryExecutor, NativeQueryExecutor, ValuesCriteriaQueryExecutor

public abstract class GenericQueryExecutor
extends java.lang.Object
implements IMultiClassQueryExecutor

Generic query executor. This class does all the job of iterating in the object list and call particular query matching to check if the object must be included in the query result.

If the query has index, An execution plan is calculated to optimize the execution. The query execution plan is calculated by subclasses (using abstract method getExecutionPlan).

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	LOG_ID

Constructor Summary

Constructors

Constructor and Description
GenericQueryExecutor(IQuery query, IStorageEngine engine)

Method Summary

Modifier and Type	Method and Description
OdbComparable	buildOrderByKey(AttributeValuesMap values)
OdbComparable	buildOrderByKey(NonNativeObjectInfo nnoi)
OdbComparable	buildOrderByKey(java.lang.Object object) TODO very bad.
abstract java.lang.Comparable	computeIndexKey(ClassInfo ci, ClassInfoIndex index)
<T> Objects<T>	execute(boolean inMemory, int startIndex, int endIndex, boolean returnObjects, IMatchingObjectAction queryResultAction) The main query execution method
boolean	executeStartAndEndOfQueryAction() Used to indicate if the execute method must call start and end method of the queryResultAction.
abstract java.lang.Object	getCurrentObjectMetaRepresentation() This can be a NonNAtiveObjectInf or AttributeValuesMap
abstract IQueryExecutionPlan	getExecutionPlan()
abstract java.lang.String	getFullClassName(IQuery query)
IQuery	getQuery()
IStorageEngine	getStorageEngine()
abstract boolean	matchObjectWithOid(OID oid, boolean loadObjectInfo, boolean inMemory) Check if the object with oid matches the query, returns true This method must compute the next object oid and the orderBy key if it exists!
abstract void	prepareQuery()
void	setClassInfo(ClassInfo classInfo) The class on which to execute the query
void	setExecuteStartAndEndOfQueryAction(boolean yes)

Methods inherited from class java.lang.Object

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

Field Detail

LOG_ID

public static final java.lang.String LOG_ID

See Also:

Constant Field Values

Constructor Detail

GenericQueryExecutor

public GenericQueryExecutor(IQuery query,
                            IStorageEngine engine)

Method Detail

getExecutionPlan

public abstract IQueryExecutionPlan getExecutionPlan()

prepareQuery

public abstract void prepareQuery()

computeIndexKey

public abstract java.lang.Comparable computeIndexKey(ClassInfo ci,
                                                     ClassInfoIndex index)

getCurrentObjectMetaRepresentation

public abstract java.lang.Object getCurrentObjectMetaRepresentation()

This can be a NonNAtiveObjectInf or AttributeValuesMap

Returns:

matchObjectWithOid

public abstract boolean matchObjectWithOid(OID oid,
                                           boolean loadObjectInfo,
                                           boolean inMemory)

Check if the object with oid matches the query, returns true This method must compute the next object oid and the orderBy key if it exists!

Parameters:

oid - The object position

loadObjectInfo - To indicate if object must loaded (when the query indicator 'in memory' is false, we do not need to load object, only ids)

inMemory - To indicate if object must be actually loaded to memory

execute

public <T> Objects<T> execute(boolean inMemory,
                              int startIndex,
                              int endIndex,
                              boolean returnObjects,
                              IMatchingObjectAction queryResultAction)

Description copied from interface: IQueryExecutor

The main query execution method

Specified by:

execute in interface IQueryExecutor

Returns:

getFullClassName

public abstract java.lang.String getFullClassName(IQuery query)

Specified by:

getFullClassName in interface IQueryExecutor

buildOrderByKey

public OdbComparable buildOrderByKey(java.lang.Object object)

TODO very bad. Should remove the instanceof

Parameters:

object -

Returns:

buildOrderByKey

public OdbComparable buildOrderByKey(NonNativeObjectInfo nnoi)

buildOrderByKey

public OdbComparable buildOrderByKey(AttributeValuesMap values)

executeStartAndEndOfQueryAction

public boolean executeStartAndEndOfQueryAction()

Description copied from interface: IMultiClassQueryExecutor

Used to indicate if the execute method must call start and end method of the queryResultAction. The default is yes. For MultiClass Query executor, it is set to false to avoid to reset the result

Specified by:

executeStartAndEndOfQueryAction in interface IMultiClassQueryExecutor

Returns:

true or false to indicate if start and end method of queryResultAction must be executed

setExecuteStartAndEndOfQueryAction

public void setExecuteStartAndEndOfQueryAction(boolean yes)

Specified by:

setExecuteStartAndEndOfQueryAction in interface IMultiClassQueryExecutor

getStorageEngine

public IStorageEngine getStorageEngine()

Specified by:

getStorageEngine in interface IMultiClassQueryExecutor

getQuery

public IQuery getQuery()

Specified by:

getQuery in interface IMultiClassQueryExecutor

setClassInfo

public void setClassInfo(ClassInfo classInfo)

Description copied from interface: IMultiClassQueryExecutor

The class on which to execute the query

Specified by:

setClassInfo in interface IMultiClassQueryExecutor