类 MessageChannelPartitionHandler
- java.lang.Object
- org.springframework.batch.integration.partition.MessageChannelPartitionHandler
- 所有已实现的接口:
PartitionHandler
,org.springframework.beans.factory.InitializingBean
@MessageEndpoint public class MessageChannelPartitionHandler extends java.lang.Object implements PartitionHandler, org.springframework.beans.factory.InitializingBean
APartitionHandler
that usesMessageChannel
instances to send instructions to remote workers and receive their responses. TheMessageChannel
provides a nice abstraction so that the location of the workers and the transport used to communicate with them can be changed at run time. The communication with the remote workers does not need to be transactional or have guaranteed delivery, so a local thread pool based implementation works as well as a remote web service or JMS implementation. If a remote worker fails, the job will fail and can be restarted to pick up missing messages and processing. The remote workers need access to the Spring BatchJobRepository
so that the shared state across those restarts can be managed centrally. While aMessageChannel
is used for sending the requests to the workers, the worker's responses can be obtained in one of two ways:- A reply channel - Slaves will respond with messages that will be aggregated via this component.
- Polling the job repository - Since the state of each slave is maintained independently within the job repository, we can poll the store to determine the state without the need of the slaves to formally respond.
- 作者:
- Dave Syer, Will Schipp, Michael Minella, Mahmoud Ben Hassine
构造器概要
构造器 构造器 说明 MessageChannelPartitionHandler()
方法概要
所有方法 实例方法 具体方法 修饰符和类型 方法 说明 void
afterPropertiesSet()
java.util.List<?>
aggregate(java.util.List<?> messages)
java.util.Collection<StepExecution>
handle(StepExecutionSplitter stepExecutionSplitter, StepExecution masterStepExecution)
SendsStepExecutionRequest
objects to the request channel of theMessagingTemplate
, and then receives the result back as a list ofStepExecution
on a reply channel.void
setDataSource(javax.sql.DataSource dataSource)
DataSource
pointing to the job repositoryvoid
setGridSize(int gridSize)
Passed to theStepExecutionSplitter
in thehandle(StepExecutionSplitter, StepExecution)
method, instructing it how manyStepExecution
instances are required, ideally.void
setJobExplorer(JobExplorer jobExplorer)
JobExplorer
to use to query the job repository.void
setMessagingOperations(org.springframework.integration.core.MessagingTemplate messagingGateway)
A pre-configured gateway for sending and receiving messages to the remote workers.void
setPollInterval(long pollInterval)
How often to poll the job repository for the status of the slaves.void
setReplyChannel(org.springframework.messaging.PollableChannel replyChannel)
void
setStepName(java.lang.String stepName)
The name of theStep
that will be used to execute the partitionedStepExecution
.void
setTimeout(long timeout)
When using job repository polling, the time limit to wait.
构造器详细资料
MessageChannelPartitionHandler
public MessageChannelPartitionHandler()
方法详细资料
afterPropertiesSet
public void afterPropertiesSet() throws java.lang.Exception
- 指定者:
afterPropertiesSet
在接口中org.springframework.beans.factory.InitializingBean
- 抛出:
java.lang.Exception
setTimeout
public void setTimeout(long timeout)
When using job repository polling, the time limit to wait.- 参数:
timeout
- milliseconds to wait, defaults to -1 (no timeout).
setJobExplorer
public void setJobExplorer(JobExplorer jobExplorer)
JobExplorer
to use to query the job repository. Either this or aDataSource
is required when using job repository polling.- 参数:
jobExplorer
-JobExplorer
to use for lookups
setPollInterval
public void setPollInterval(long pollInterval)
How often to poll the job repository for the status of the slaves.- 参数:
pollInterval
- milliseconds between polls, defaults to 10000 (10 seconds).
setDataSource
public void setDataSource(javax.sql.DataSource dataSource)
DataSource
pointing to the job repository- 参数:
dataSource
-DataSource
that points to the job repository's store
setMessagingOperations
public void setMessagingOperations(org.springframework.integration.core.MessagingTemplate messagingGateway)
A pre-configured gateway for sending and receiving messages to the remote workers. Using this property allows a large degree of control over the timeouts and other properties of the send. It should have channels set up internally:- request channel capable of accepting
StepExecutionRequest
payloads - reply channel that returns a list of
StepExecution
results
- 参数:
messagingGateway
- theMessagingTemplate
to set
- request channel capable of accepting
setGridSize
public void setGridSize(int gridSize)
Passed to theStepExecutionSplitter
in thehandle(StepExecutionSplitter, StepExecution)
method, instructing it how manyStepExecution
instances are required, ideally. TheStepExecutionSplitter
is allowed to ignore the grid size in the case of a restart, since the input data partitions must be preserved.- 参数:
gridSize
- the number of step executions that will be created
setStepName
public void setStepName(java.lang.String stepName)
The name of theStep
that will be used to execute the partitionedStepExecution
. This is a regular Spring Batch step, with all the business logic required to complete an execution based on the input parameters in itsStepExecution
context. The name will be translated into aStep
instance by the remote worker.- 参数:
stepName
- the name of theStep
instance to execute business logic
aggregate
@Aggregator(sendPartialResultsOnExpiry="true") public java.util.List<?> aggregate(@Payloads java.util.List<?> messages)
- 参数:
messages
- the messages to be aggregated- 返回:
- the list as it was passed in
setReplyChannel
public void setReplyChannel(org.springframework.messaging.PollableChannel replyChannel)
handle
public java.util.Collection<StepExecution> handle(StepExecutionSplitter stepExecutionSplitter, StepExecution masterStepExecution) throws java.lang.Exception
SendsStepExecutionRequest
objects to the request channel of theMessagingTemplate
, and then receives the result back as a list ofStepExecution
on a reply channel. Use theaggregate(List)
method as an aggregator of the individual remote replies. The receive timeout needs to be set realistically in theMessagingTemplate
and the aggregator, so that there is a good chance of all work being done.- 指定者:
handle
在接口中PartitionHandler
- 参数:
stepExecutionSplitter
- a strategy for generating a collection ofStepExecution
instancesmasterStepExecution
- the master step execution for the whole partition- 返回:
- a collection of completed
StepExecution
instances - 抛出:
java.lang.Exception
- if anything goes wrong. This allows implementations to be liberal and rely on the caller to translate an exception into a step failure as necessary.- 另请参阅:
PartitionHandler.handle(StepExecutionSplitter, StepExecution)