com.neurosys.modules.etl

Class EntityBabyPersistTransformer<E>

java.lang.Object

com.neurosys.modules.etl.EntityPersistTransformer<E>

com.neurosys.modules.etl.EntityBabyPersistTransformer<E>

Type Parameters:

E - of Entity type
TODO: Add unit test case

All Implemented Interfaces:

FailFastAware, RealTimeWriter<E>, Writer, org.apache.commons.collections.Transformer

public class EntityBabyPersistTransformer<E>
extends EntityPersistTransformer<E>

This Transformer will ensure that the entity is persisted and return back the passed in input.
During ETL it is possible that an existing PARENT (input), entity may have new Objects associated with it.
During a persist it maybe required that these associated entities are FIRST persisted before the main parent entity is.


Differs from RelatedEntityPersistTransformer : This variant is more apt for Updates or simpler cases of updates.

Author:

Arjun Dhar

See Also:

EntityPersistTransformer, RelatedEntityPersistTransformer

Field Summary

Fields inherited from class com.neurosys.modules.etl.EntityPersistTransformer

em, exceptions, failFast, messages, tm

Constructor Summary

Constructors

Constructor and Description
EntityBabyPersistTransformer()

Method Summary

Modifier and Type	Method and Description
Object	getFieldAccessor() The field name or accessor, can be a String or a TwoWayTransformer. If a Transformer then it will apply it over the input to derive the object to persist if its a new born.
EntityFieldSetter<E,Object>	getFieldPersist() Once the new born object is persisted the resultant entity is put back into the parent.
org.apache.commons.collections.Predicate	getPersistCritera() Checks the field specified by fieldAccessor if this needs to be persisted or not.
boolean	isPersist() If true will EntityManager.persist(Object) else will use EntityManager.merge(Object)
void	setFieldAccessor(Object fieldAccessor) The field name or accessor, can be a String or a TwoWayTransformer. If a Transformer then it will apply it over the input to derive the object to persist if its a new born.
void	setFieldPersist(EntityFieldSetter<E,Object> fieldPersist) Once the new born object is persisted the resultant entity is put back into the parent.
void	setPersist(boolean persist) If true will EntityManager.persist(Object) else will use EntityManager.merge(Object)
void	setPersistCritera(org.apache.commons.collections.Predicate persistCritera) Checks the field specified by fieldAccessor if this needs to be persisted or not.
E	write(E record) Write a record
protected void	write(E record, Object child) Write child to parent record

Methods inherited from class com.neurosys.modules.etl.EntityPersistTransformer

close, getExceptions, getMessages, getTransactionDef, handleException, init, isExecuteUnderTransaction, isFailFast, isInitialized, setExceptions, setExecuteUnderTransaction, setFailFast, setMessages, setTransactionDef, transform, write

Methods inherited from class java.lang.Object

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

Constructor Detail

EntityBabyPersistTransformer

public EntityBabyPersistTransformer()

Method Detail

write

protected void write(E record,
                     Object child)

Write child to parent record

Parameters:

record - as E

child - as Object

write

public E write(E record)

Description copied from interface: RealTimeWriter

Write a record

Specified by:

write in interface RealTimeWriter<E>

Overrides:

write in class EntityPersistTransformer<E>

getFieldAccessor

public Object getFieldAccessor()

The field name or accessor, can be a String or a TwoWayTransformer.
If a Transformer then it will apply it over the input to derive the object to persist if its a new born. If fieldPersist is not null, and this is not a String, then fieldAccessor will be used as a TwoWayTransformer.from(Object) to take the parent object and derive the field name in that represents the child entity

Can be null:

false

setFieldAccessor

public void setFieldAccessor(Object fieldAccessor)

The field name or accessor, can be a String or a TwoWayTransformer.
If a Transformer then it will apply it over the input to derive the object to persist if its a new born. If fieldPersist is not null, and this is not a String, then fieldAccessor will be used as a TwoWayTransformer.from(Object) to take the parent object and derive the field name in that represents the child entity

Can be null:

false

getFieldPersist

public EntityFieldSetter<E,Object> getFieldPersist()

Once the new born object is persisted the resultant entity is put back into the parent.

Can be null:

true

setFieldPersist

public void setFieldPersist(EntityFieldSetter<E,Object> fieldPersist)

Once the new born object is persisted the resultant entity is put back into the parent.

Can be null:

true

isPersist

public boolean isPersist()

If true will EntityManager.persist(Object) else will use EntityManager.merge(Object)

setPersist

public void setPersist(boolean persist)

If true will EntityManager.persist(Object) else will use EntityManager.merge(Object)

getPersistCritera

public org.apache.commons.collections.Predicate getPersistCritera()

Checks the field specified by fieldAccessor if this needs to be persisted or not. Predicate.evaluate(Object) = true implies it will be persisted

If this field is null the evaluation criteria is to check for an "id" field in the NewBorn if thats null
If this is null; then write(Object, Object) will always be called.

setPersistCritera

public void setPersistCritera(org.apache.commons.collections.Predicate persistCritera)

Checks the field specified by fieldAccessor if this needs to be persisted or not. Predicate.evaluate(Object) = true implies it will be persisted

If this field is null the evaluation criteria is to check for an "id" field in the NewBorn if thats null
If this is null; then write(Object, Object) will always be called.