org.camunda.bpm.engine.cassandra.provider.operation

Class JobOperations

java.lang.Object

org.camunda.bpm.engine.cassandra.provider.operation.AbstractEntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>

org.camunda.bpm.engine.cassandra.provider.operation.JobOperations

All Implemented Interfaces:

EntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>, org.camunda.bpm.engine.impl.db.EntityLoadListener

public class JobOperations
extends AbstractEntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>
implements org.camunda.bpm.engine.impl.db.EntityLoadListener

Jobs are essentially stored in a queue, which is a bad idea in Cassandra generally. The queue is sharded to avoid the tombstone issues, however it will still cause hot spots in the cassandra cluster. This implementation can support small to medium throughput (please don't ask me for specific numbers) For medium / large implementations use a proper queue. Unlocked jobs are stored separately from the locked jobs. Unlocked jobs are sorted by job due date and are always returned in this order. Locked jobs are sorted by the lock expiry time. The jobs where the locks have expired are always selected before unlocked jobs on the premise that they have already gone through the job prioritization waited for the lock expiry interval and generally need to be executed yesterday After much dithering we've decided not to support priorities, use a queue if priorities are required

Author:

Natalia Levine

Field Summary

Fields

Modifier and Type	Field and Description
protected static Map<Class<?>,IndexHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>>	indexHandlers
protected static int	shardInitNumber
protected static int	shardSizeMillis

Constructor Summary

Constructors

Constructor and Description
JobOperations(CassandraPersistenceSession cassandraPersistenceSession)

Method Summary

Methods

Modifier and Type	Method and Description
protected void	bindKeyFields(CassandraPersistenceSession session, org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity, com.datastax.driver.core.BoundStatement statement)
void	delete(CassandraPersistenceSession session, org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)
protected void	deleteIndex(CassandraPersistenceSession session, org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)
protected Class<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>	getEntityType()
static IndexHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>	getIndexHandler(Class<?> type)
protected String	getTableName()
void	insert(CassandraPersistenceSession session, org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)
protected void	insertIndex(CassandraPersistenceSession session, org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)
void	onEntityLoaded(org.camunda.bpm.engine.impl.db.DbEntity entity)
static void	prepare(CassandraProcessEngineConfiguration config)
void	update(CassandraPersistenceSession session, org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)

Methods inherited from class org.camunda.bpm.engine.cassandra.provider.operation.AbstractEntityOperationHandler

getEntityById

Methods inherited from class java.lang.Object

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

Field Detail

shardSizeMillis

protected static int shardSizeMillis

shardInitNumber

protected static int shardInitNumber

indexHandlers

protected static Map<Class<?>,IndexHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>> indexHandlers

Constructor Detail

JobOperations

public JobOperations(CassandraPersistenceSession cassandraPersistenceSession)

Method Detail

prepare

public static void prepare(CassandraProcessEngineConfiguration config)

insert

public void insert(CassandraPersistenceSession session,
          org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)

Specified by:

insert in interface EntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>

insertIndex

protected void insertIndex(CassandraPersistenceSession session,
               org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)

bindKeyFields

protected void bindKeyFields(CassandraPersistenceSession session,
                 org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity,
                 com.datastax.driver.core.BoundStatement statement)

delete

public void delete(CassandraPersistenceSession session,
          org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)

Specified by:

delete in interface EntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>

deleteIndex

protected void deleteIndex(CassandraPersistenceSession session,
               org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)

update

public void update(CassandraPersistenceSession session,
          org.camunda.bpm.engine.impl.persistence.entity.JobEntity entity)

Specified by:

update in interface EntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>

onEntityLoaded

public void onEntityLoaded(org.camunda.bpm.engine.impl.db.DbEntity entity)

Specified by:

onEntityLoaded in interface org.camunda.bpm.engine.impl.db.EntityLoadListener

getEntityType

protected Class<org.camunda.bpm.engine.impl.persistence.entity.JobEntity> getEntityType()

Specified by:

getEntityType in class AbstractEntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>

getTableName

protected String getTableName()

Specified by:

getTableName in class AbstractEntityOperationHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity>

getIndexHandler

public static IndexHandler<org.camunda.bpm.engine.impl.persistence.entity.JobEntity> getIndexHandler(Class<?> type)