com.devonfw.module.basic.common.api.to

Class AbstractEto

java.lang.Object

com.devonfw.module.basic.common.api.to.AbstractTo

com.devonfw.module.basic.common.api.to.AbstractEto

All Implemented Interfaces:

GenericEntity<Long>, Serializable

Direct Known Subclasses:

RevisionedEto

public abstract class AbstractEto
extends AbstractTo
implements GenericEntity<Long>

This is the abstract base class for an transfer-object that contains all the data properties of an entity without its relations. This is called ETO (entity transfer object). Sometimes in other contexts people also call this DTO (data transfer object).
Here, data properties are the properties using a datatype (immutable value type such as String, Number, Instant, custom-datatype, etc.). Relations of an @link GenericEntity entity} are not contained except for IDs of javax.persistence.OneToOne relations. Instead of using Long we recommend to use IdRef to be type-safe and more expressive. For actual relations you will use CTOs to express what set of entities to transfer, load, save, update, etc. without redundancies.
Classes extending this class should carry the suffix Eto.

Since:

3.0.0

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AbstractEto.PersistentEntityAccess Inner class to grant access to internal persistent entity reference of an AbstractEto.

Field Summary

Fields

Modifier and Type	Field and Description
private Long	id
private int	modificationCounter
private GenericEntity<Long>	persistentEntity
private static long	serialVersionUID

Constructor Summary

Constructors

Constructor and Description
AbstractEto() The constructor.

Method Summary

Modifier and Type	Method and Description
Long	getId()
int	getModificationCounter() This method gets the current modification-counter of this entity.
void	setId(Long id)
void	setModificationCounter(int version)
protected void	toString(StringBuilder buffer) Method to extend AbstractTo.toString() logic.

Methods inherited from class com.devonfw.module.basic.common.api.to.AbstractTo

toString

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

id

private Long id

modificationCounter

private int modificationCounter

persistentEntity

private transient GenericEntity<Long> persistentEntity

Constructor Detail

AbstractEto

public AbstractEto()

The constructor.

Method Detail

getId

public Long getId()

Specified by:

getId in interface GenericEntity<Long>

Returns:

the primary key (unique identifier) of this entity. May be null if this entity is transient (not yet saved in the database). While this method is initially defined in a generic way, it is strongly recommended to use Long as datatype for IDs.
Even if you want to have a String-based business-oriented identifier it is best practice to use a Long as primary key and add the business identifier as additional field (with a unique constraint). This way references to the entity will be a lot more compact and improve your performance in JOINs or the like. However, there may be reasons to use other datatypes for the ID. In any case the unique ID should be an immutable java-object that can be rebuild from its string-representation.
Please note that if your ID has a specific syntax, semantic, formatting rules, etc. you should create a custom datatype for it. If it can easily be mapped to a Long value you can still use Long here and provide a transient getter method that returns the your custom datatype from the Long.

See Also:

javax.persistence.Id

setId

public void setId(Long id)

Specified by:

setId in interface GenericEntity<Long>

Parameters:

id - the new primary key. This method shall typically only be used by technical frameworks such as hibernate.

getModificationCounter

public int getModificationCounter()

Description copied from interface: GenericEntity

This method gets the current modification-counter of this entity. Whenever the object gets modified and persisted, this counter will be increased (typically after the transaction is closed). The initial value after construction is 0.
This property is often simply called version. However, as this sometimes causes confusion or may conflict with a business property "version", we use the more technical and self-explanatory name modificationCounter.
If this feature is NOT supported for some reason, this method should always return 0.

Specified by:

getModificationCounter in interface GenericEntity<Long>

Returns:

the current modification-counter.

See Also:

javax.persistence.Version, javax.persistence.Version

setModificationCounter

public void setModificationCounter(int version)

Specified by:

setModificationCounter in interface GenericEntity<Long>

Parameters:

version - the new modification counter. This method shall typically only be used by technical frameworks such as hibernate.

toString

protected void toString(StringBuilder buffer)

Method to extend AbstractTo.toString() logic.

Overrides:

toString in class AbstractTo

Parameters:

buffer - is the StringBuilder where to append the string representation.