Package org.seedstack.business.domain

Interface Repository<A extends AggregateRoot<I>,I>

Type Parameters:

A - the type of the aggregate root class.

I - the type of identifier of the aggregate root class.

@DomainRepository
public interface Repository<A extends AggregateRoot<I>,I>

A repository is responsible for consistently storing and retrieving a whole aggregate. It has a simple collection-like global interface and optionally domain-specific methods.

A repository is responsible for storing and retrieve a whole aggregate. It manipulates the aggregate through its root entity. It cannot directly store or retrieve parts of the aggregate.

A repository provides the illusion of an in-memory collection of all objects that are of the corresponding aggregate root type.

A repository implements a well-known interface that provides methods for adding, removing and querying objects.

A repository optionally implements methods that select objects based on criteria meaningful to domain experts. Those methods return fully instantiated objects or collections of objects whose attribute values meet the criteria.

Example:

 public interface SomeRepository extends Repository<SomeAggregate, SomeId> {
     // Optional business-meaningful methods
     List<SomeAggregate> objectsByCategory(String category);
 }

 public class SomeJpaRepository implements SomeRepository {
    @Override
     public List<SomeAggregate> objectsByCategory(String category) {
         // implement specific query
     }
 }
 

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	Repository.Option	Marker interface for options that can be used to alter the results of some repository methods.

Method Summary

Modifier and Type	Method	Description
void	add(A aggregate)	Adds an aggregate to the repository.
default A	addOrUpdate(A aggregate)	Adds an aggregate to the repository or updates it if it already exists.
default void	clear()	Removes all aggregates from the repository.
default boolean	contains(A aggregate)	Checks that the specified aggregate is present in the repository.
default boolean	contains(I id)	Checks that the aggregate identified by the specified identifier is present in the repository.
default boolean	contains(Specification<A> specification)	Check if at least one aggregate satisfying the specified specification is present in the repository.
default long	count(Specification<A> specification)	Count the number of aggregates in the repository satisfying the given specification.
default Optional<A>	get(I id)	Gets an aggregate identified by its identifier.
Stream<A>	get(Specification<A> specification, Repository.Option... options)	Finds all aggregates in the repository satisfying the given specification.
Class<A>	getAggregateRootClass()	Returns the aggregate root class managed by the repository.
Class<I>	getIdentifierClass()	Returns the aggregate root identifier class managed by the repository.
SpecificationBuilder	getSpecificationBuilder()	Access to the specification builder.
default boolean	isEmpty()	Return true if the repository is empty (i.e.
default void	remove(A aggregate)	Removes the specified aggregate from the repository.
default void	remove(I id)	Removes the existing aggregate identified with the specified identifier.
long	remove(Specification<A> specification)	Removes all aggregates in the repository satisfying the given specification.
default long	size()	Returns the number of aggregates in the repository.
default A	update(A aggregate)	Updates an existing aggregate with the specified instance.

Method Detail

add

void add(A aggregate)
  throws AggregateExistsException

Adds an aggregate to the repository.

Parameters:

aggregate - the aggregate to add.

Throws:

AggregateExistsException - if the repository already contains the aggregate.

get

Stream<A> get(Specification<A> specification,
              Repository.Option... options)

Finds all aggregates in the repository satisfying the given specification. Options can be specified to alter the returned stream (order, limits, ...).

Parameters:

specification - the specification aggregates must satisfy.

options - result options.

Returns:

a stream of aggregates.

See Also:

Repository.Option

get

default Optional<A> get(I id)

Gets an aggregate identified by its identifier.

Parameters:

id - the aggregate identifier.

Returns:

an optional of the corresponding aggregate.

contains

default boolean contains(Specification<A> specification)

Check if at least one aggregate satisfying the specified specification is present in the repository.

Parameters:

specification - the specification.

Returns:

true if at least one aggregate satisfying the specification is present, false otherwise.

contains

default boolean contains(I id)

Checks that the aggregate identified by the specified identifier is present in the repository.

Parameters:

id - the aggregate identifier.

Returns:

true if the aggregate is present, false otherwise.

contains

default boolean contains(A aggregate)

Checks that the specified aggregate is present in the repository. The check is only done on the aggregate identity, so this method is equivalent to calling contains(aggregate.getId() ).

Parameters:

aggregate - the aggregate identifier.

Returns:

true if the aggregate is present, false otherwise.

count

default long count(Specification<A> specification)

Count the number of aggregates in the repository satisfying the given specification.

Parameters:

specification - the specification aggregates must satisfy.

Returns:

the number of aggregates in the repository satisfying the specification.

size

default long size()

Returns the number of aggregates in the repository.

Returns:

the number of aggregates in the repository.

isEmpty

default boolean isEmpty()

Return true if the repository is empty (i.e. contains no aggregate) and false otherwise (i.e. contains at least one aggregate).

Returns:

true if repository is empty, false otherwise.

remove

long remove(Specification<A> specification)
     throws AggregateNotFoundException

Removes all aggregates in the repository satisfying the given specification.

Parameters:

specification - the specification aggregates must satisfy.

Returns:

the number of aggregates removed from the repository.

Throws:

AggregateNotFoundException - if the repository doesn't contain the aggregate.

remove

default void remove(I id)
             throws AggregateNotFoundException

Removes the existing aggregate identified with the specified identifier.

Parameters:

id - the identifier of the aggregate to remove.

Throws:

AggregateNotFoundException - if the repository doesn't contain the aggregate.

remove

default void remove(A aggregate)
             throws AggregateNotFoundException

Removes the specified aggregate from the repository.

Parameters:

aggregate - the aggregate to remove.

Throws:

AggregateNotFoundException - if the repository doesn't contain the aggregate.

update

default A update(A aggregate)
          throws AggregateNotFoundException

Updates an existing aggregate with the specified instance.

Parameters:

aggregate - the aggregate to update.

Returns:

the update aggregate.

Throws:

AggregateNotFoundException - if the repository doesn't contain the aggregate.

addOrUpdate

default A addOrUpdate(A aggregate)

Adds an aggregate to the repository or updates it if it already exists. This operation can be useful in some circumstances but operations with clearer semantics like add(A) and update(AggregateRoot) should be preferred.

Parameters:

aggregate - the aggregate to update.

Returns:

the update aggregate.

Throws:

AggregateNotFoundException - if the repository doesn't contain the aggregate.

clear

default void clear()

Removes all aggregates from the repository.

getAggregateRootClass

Class<A> getAggregateRootClass()

Returns the aggregate root class managed by the repository.

Returns:

the aggregate root class.

getIdentifierClass

Class<I> getIdentifierClass()

Returns the aggregate root identifier class managed by the repository.

Returns:

the aggregate root identifier.

getSpecificationBuilder

SpecificationBuilder getSpecificationBuilder()

Access to the specification builder.

Returns:

the specification builder.