com.neurosys.modules.etl

Class QueryResultArrayToEntityTransformer<ENTITY>

java.lang.Object

com.neurosys.etl.process.EventAwareProcess

com.neurosys.etl.common.transformers.AbstractEntityTransformer<TUPLE,CELL,ENTITY>

com.neurosys.etl.common.transformers.AbstractTupleToEntityTransformer<Object[],com.neurosys.etl.common.transformers.ObjectArrayToEntityTransformer.Cell,ENTITY>

com.neurosys.etl.common.transformers.ObjectArrayToEntityTransformer<ENTITY>

com.neurosys.modules.etl.QueryResultArrayToEntityTransformer<ENTITY>

Type Parameters:

ENTITY -

All Implemented Interfaces:

QueryOptimizer, IdempotentAware, ModeAware, Process, Serializable, org.apache.commons.collections.Transformer

public class QueryResultArrayToEntityTransformer<ENTITY>
extends ObjectArrayToEntityTransformer<ENTITY>
implements QueryOptimizer

An ObjectArrayToEntityTransformer that also provides a replaceEntityString(String, String) to prepare the actual Query to return the result array in the expected format as defined by AbstractEntityTransformer.getColumnFieldMapping()

Author:

Arjun Dhar

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface com.neurosys.etl.process.Process

Process.Event, Process.EventPoint

Field Summary

Fields inherited from class com.neurosys.etl.common.transformers.ObjectArrayToEntityTransformer

type

Fields inherited from class com.neurosys.etl.common.transformers.AbstractEntityTransformer

columnFieldMapping, idempotent, mode, modesSupported, nestedObjectInitMap, nonAssociatedMappers

Fields inherited from class com.neurosys.etl.process.EventAwareProcess

listeners, processState

Constructor Summary

Constructors

Constructor and Description
QueryResultArrayToEntityTransformer()
QueryResultArrayToEntityTransformer(Class<ENTITY> type, List<String> fieldNames, boolean inverse)
QueryResultArrayToEntityTransformer(Class<ENTITY> type, Map<Integer,Mapper> columnFieldMapping)
QueryResultArrayToEntityTransformer(Class<ENTITY> type, org.apache.commons.collections.Transformer fieldNamesTransformer, Object fieldNames, boolean inverse)

Method Summary

Modifier and Type	Method and Description
String	getOverrideFromClause() Optional override of FROM clause over the default Query From to be optimized by specifying one.
void	morphQuery(Query q) Converts the AbstractEntityTransformer.getColumnFieldMapping() into the Query.setIncludedFields(List)
String	replaceEntityString(String query, String entityAlias) For a given query String, replace entity with the equivalent fields in the order specified in AbstractEntityTransformer.getColumnFieldMapping()
void	setOverrideFromClause(String overrideFromClause) Optional override of FROM clause over the default Query From to be optimized by specifying one.
Object	transform(Object input) Work Horse method that does all the conversion using Mappers.

Methods inherited from class com.neurosys.etl.common.transformers.ObjectArrayToEntityTransformer

getColumnIndex, getColumns, getDeclaredFields, getTuple, getTupleIndex, getTupleIndexFromCol, getType, getValue, init, setType

Methods inherited from class com.neurosys.etl.common.transformers.AbstractTupleToEntityTransformer

identifyNode

Methods inherited from class com.neurosys.etl.common.transformers.AbstractEntityTransformer

consumeIntermediateObjects, getColumnFieldMapping, getEntityAccessTransformer, getMode, getModesSupported, getNestedObjectInitMap, getNonAssiciatedMappers, getNonAssociatedMappers, getValue, init, isIdempotent, nestedInit, processValue, setColumnFieldMapping, setEntity, setEntityAccessTransformer, setIdempotent, setMode, setModesSupported, setNestedObjectInitMap, setNonAssociatedMappers

Methods inherited from class com.neurosys.etl.process.EventAwareProcess

addListener, getListeners, onChangeHandler, setListeners

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryResultArrayToEntityTransformer

public QueryResultArrayToEntityTransformer()

QueryResultArrayToEntityTransformer

public QueryResultArrayToEntityTransformer(Class<ENTITY> type,
                                           List<String> fieldNames,
                                           boolean inverse)

QueryResultArrayToEntityTransformer

public QueryResultArrayToEntityTransformer(Class<ENTITY> type,
                                           Map<Integer,Mapper> columnFieldMapping)

QueryResultArrayToEntityTransformer

public QueryResultArrayToEntityTransformer(Class<ENTITY> type,
                                           org.apache.commons.collections.Transformer fieldNamesTransformer,
                                           Object fieldNames,
                                           boolean inverse)

Parameters:

type - as Entity type

fieldNamesTransformer - as Transformer that will process the fieldNames in any type

fieldNames - in any type that the fieldNamesTransformer can transform into a List

inverse - as boolean. If true the fieldNames become excluded ratehr than included.

Method Detail

transform

public Object transform(Object input)

Description copied from class: AbstractTupleToEntityTransformer

Work Horse method that does all the conversion using Mappers.
Mapping involved One-to-One mapping or mapping Hypothetical variables in the source to real ones in persistence.

Specified by:

transform in interface QueryOptimizer

Specified by:

transform in interface org.apache.commons.collections.Transformer

Overrides:

transform in class AbstractTupleToEntityTransformer<Object[],com.neurosys.etl.common.transformers.ObjectArrayToEntityTransformer.Cell,ENTITY>

replaceEntityString

public String replaceEntityString(String query,
                                  String entityAlias)

For a given query String, replace entity with the equivalent fields in the order specified in AbstractEntityTransformer.getColumnFieldMapping()

Specified by:

replaceEntityString in interface QueryOptimizer

Parameters:

query - as String originally expected to return ENTITY

entityAlias - as the variable representing the entity in the query in the SELECT clause

Returns:

String as modified query expected to return Object[]

morphQuery

public void morphQuery(Query q)

Converts the AbstractEntityTransformer.getColumnFieldMapping() into the Query.setIncludedFields(List)

Specified by:

morphQuery in interface QueryOptimizer

Parameters:

q - as Query

getOverrideFromClause

public String getOverrideFromClause()

Optional override of FROM clause over the default Query From to be optimized by specifying one. While replacing some select fields Joins maybe impacted, and may require manual re-definition of the FROM clause

setOverrideFromClause

public void setOverrideFromClause(String overrideFromClause)

Optional override of FROM clause over the default Query From to be optimized by specifying one. While replacing some select fields Joins maybe impacted, and may require manual re-definition of the FROM clause