org.eiichiro.acidhouse

Interface ResourceManager<T>

public interface ResourceManager<T>

ResourceManager manages an entity instance, datastore connection corresponding to the entity and its transactional state. ResourceManager is instantiated and invoked by Session and Coordinator (especially, in distributed transaction), and applies datastore operation to the managed entity with the datastore-specific APIs.

Author:

Eiichiro Uchiumi

Method Summary

Methods

Modifier and Type	Method and Description
void	commit() Applies the transactional operation (WAL: Write Ahead Log) to the managed entity then frees the allocated lock.
void	delete(Object entity) Deletes the specified entity from the datastore.
Object	entity() Returns the managed entity instance.
<E> E	get(Class<E> clazz, Object key) Gets the entity instance of the specified Class corresponding to the specified id.
void	prepare() Allocates lock for the managed entity.
void	put(Object entity) Puts the specified entity instance into the datastore newly.
T	transaction() Returns the current transaction.
void	update(Object entity) Applies the specified entity's update to the datastore.

Method Detail

get

<E> E get(Class<E> clazz,
        Object key)
      throws ConcurrentModificationException,
             IndoubtException

Gets the entity instance of the specified Class corresponding to the specified id.

Type Parameters:

E - The type of entity.

Parameters:

clazz - The Class of entity.

key - The key corresponding to the entity you attempt to get.

Returns:

The entity instance of the specified Class corresponding to the specified key.

Throws:

ConcurrentModificationException - If the entity has been modified by other transaction.

IndoubtException - If the data consistency broken is detected when the entity is get.

put

void put(Object entity)

Puts the specified entity instance into the datastore newly.

Parameters:

entity - An entity instance.

update

void update(Object entity)

Applies the specified entity's update to the datastore.

Parameters:

entity - An entity instance to be updated.

delete

void delete(Object entity)

Deletes the specified entity from the datastore.

Parameters:

entity - An entity instance to be updated.

prepare

void prepare()

Allocates lock for the managed entity. This operation is the preparation for the current transaction's commitment, and invoked by Coordinator in Two-phase commit protocol.

commit

void commit()

Applies the transactional operation (WAL: Write Ahead Log) to the managed entity then frees the allocated lock. This operation is the completion for the current transaction's commitment, and incoked by Coordinator in Two-phase commit protocol.

entity

Object entity()

Returns the managed entity instance.

Returns:

The managed entity instance.

transaction

T transaction()

Returns the current transaction. If the managed entity is out of transaction, this method returns null.

Returns:

The current transaction.