org.aksw.service_framework.jpa.core

Class ServiceRepositoryJpaImpl<C,E,S>

java.lang.Object

org.aksw.service_framework.jpa.core.ServiceRepositoryJpaImpl<C,E,S>

All Implemented Interfaces:

ServiceRepository<S>, ServiceRepositoryJpa<S>

public class ServiceRepositoryJpaImpl<C,E,S>
extends Object
implements ServiceRepositoryJpa<S>

A service framework based on JPA There is assumed to be a set of service configuration objects of type C. Upon initialization of the repository, each object c of C will be used to spawn a service as follows: - First, a service execution context e of type E will be obtained: If such e already exists, such as from a prior execution of c, it will be reused. Otherwise a new instance of E will be created. - A launcher will be invoked with c and e. - The result of a launches is a ServiceProvider which has a getService() and a close() method - If the launcher fails to start the service for whatever reason, the provider is null - The repository exposes the service via a ServiceControl object, that allows retrieving the service (via getService()) as well as stopping and starting the service. Notes: - The launcher is invoked for every config object, and it is up to the launcher to decide whether to return a serviceProvider object or null. This means, enabling/disabling services must be part of the config object. TODO: We need to distinguish between a disabled service (i.e. don't bring the service up on restart) and a service that could not be brought up due to an error (i.e. retry to start on restart) In other words: Services need a 'start on boot' flag, which could be part of the cte table. TODO finish below... We actually keep track of start/stopped status in the cte table. However, if upon launch a prior executionContext is found, the service

Author:

raven

Constructor Summary

Constructors

Constructor and Description
ServiceRepositoryJpaImpl(javax.persistence.EntityManagerFactory emf, Class<C> configClass, Class<E> executionContextClass, ServiceLauncher<C,E,S> serviceLauncher)

Method Summary

Modifier and Type	Method and Description
static <C,E,S> ServiceRepositoryJpaImpl<C,E,S>	create(javax.persistence.EntityManagerFactory emf, Class<C> configClass, Class<E> executionContextClass, ServiceLauncher<C,E,S> serviceLauncher)
static void	deleteAll(javax.persistence.EntityManager em, Class<?> clazz)
static <T> List<T>	deleteAll(javax.persistence.EntityManagerFactory emf, Class<T> clazz)
void	deleteByConfigId(Object configId) Stops a service and removes its execution record
void	deleteExecutionContexts()
List<C>	getConfigs()
static <T> T	getEntity(javax.persistence.EntityManagerFactory emf, Class<T> clazz, Object id)
javax.persistence.EntityManagerFactory	getEntityManagerFactory()
List<E>	getExecutionContexts()
Map<Integer,E>	getExecutions(javax.persistence.EntityManager em, List<Integer> ids)
static List<Integer>	getIds(List<ConfigToExecution> mappings) Note: There should always be only at most one execution context, but for dealing with abnormalities we allow a list to be returned.
List<ConfigToExecution>	getMappings(javax.persistence.EntityManager em, Object configId)
List<ServiceEventListener<C,E,S>>	getServiceEventListeners()
ServiceProvider<S>	getServiceProviderByConfigId(Object configId)
ServiceState	getStateByConfigId(Object configId)
ServiceState	getStateByExecutionContextId(Object executionContextId)
ServiceState	getStateByExecutionId(Object executionId)
static <T> List<T>	listAll(javax.persistence.EntityManager em, Class<T> clazz)
static <T> List<T>	listAll(javax.persistence.EntityManagerFactory emf, Class<T> clazz)
ConfigToExecution	newCte(javax.persistence.EntityManager em, Object configId, E executionContext)
static <T> T	newEntity(javax.persistence.EntityManager em, Class<T> clazz)
void	setStatus(ConfigToExecution cte, String status)
void	startAll()
void	startAllServices() TODO This could be done in parallel
ServiceControl<S>	startByConfig(C config)
ServiceControl<S>	startByConfigId(Object id)
void	stopByConfigId(Object configId)

Methods inherited from class java.lang.Object

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

Constructor Detail

ServiceRepositoryJpaImpl

public ServiceRepositoryJpaImpl(javax.persistence.EntityManagerFactory emf,
                                Class<C> configClass,
                                Class<E> executionContextClass,
                                ServiceLauncher<C,E,S> serviceLauncher)

Method Detail

getServiceEventListeners

public List<ServiceEventListener<C,E,S>> getServiceEventListeners()

create

public static <C,E,S> ServiceRepositoryJpaImpl<C,E,S> create(javax.persistence.EntityManagerFactory emf,
                                                             Class<C> configClass,
                                                             Class<E> executionContextClass,
                                                             ServiceLauncher<C,E,S> serviceLauncher)

getEntityManagerFactory

public javax.persistence.EntityManagerFactory getEntityManagerFactory()

Specified by:

getEntityManagerFactory in interface ServiceRepositoryJpa<S>

startAll

public void startAll()

Specified by:

startAll in interface ServiceRepository<S>

getEntity

public static <T> T getEntity(javax.persistence.EntityManagerFactory emf,
                              Class<T> clazz,
                              Object id)

listAll

public static <T> List<T> listAll(javax.persistence.EntityManagerFactory emf,
                                  Class<T> clazz)

deleteAll

public static <T> List<T> deleteAll(javax.persistence.EntityManagerFactory emf,
                                    Class<T> clazz)

listAll

public static <T> List<T> listAll(javax.persistence.EntityManager em,
                                  Class<T> clazz)

deleteAll

public static void deleteAll(javax.persistence.EntityManager em,
                             Class<?> clazz)

getConfigs

public List<C> getConfigs()

getExecutionContexts

public List<E> getExecutionContexts()

deleteExecutionContexts

public void deleteExecutionContexts()

deleteByConfigId

public void deleteByConfigId(Object configId)

Stops a service and removes its execution record

Parameters:

configId -

getMappings

public List<ConfigToExecution> getMappings(javax.persistence.EntityManager em,
                                           Object configId)

getIds

public static List<Integer> getIds(List<ConfigToExecution> mappings)

Note: There should always be only at most one execution context, but for dealing with abnormalities we allow a list to be returned. The idea is basically, that if there are multiple contexts, then the database is messed up and we can just delete the contexts.

Parameters:

configId -

Returns:

getExecutions

public Map<Integer,E> getExecutions(javax.persistence.EntityManager em,
                                    List<Integer> ids)

newEntity

public static <T> T newEntity(javax.persistence.EntityManager em,
                              Class<T> clazz)

newCte

public ConfigToExecution newCte(javax.persistence.EntityManager em,
                                Object configId,
                                E executionContext)

startAllServices

public void startAllServices()

TODO This could be done in parallel

startByConfigId

public ServiceControl<S> startByConfigId(Object id)

Specified by:

startByConfigId in interface ServiceRepository<S>

startByConfig

public ServiceControl<S> startByConfig(C config)

stopByConfigId

public void stopByConfigId(Object configId)

Specified by:

stopByConfigId in interface ServiceRepository<S>

setStatus

public void setStatus(ConfigToExecution cte,
                      String status)

getServiceProviderByConfigId

public ServiceProvider<S> getServiceProviderByConfigId(Object configId)

getStateByConfigId

public ServiceState getStateByConfigId(Object configId)

getStateByExecutionId

public ServiceState getStateByExecutionId(Object executionId)

getStateByExecutionContextId

public ServiceState getStateByExecutionContextId(Object executionContextId)