org.springframework.batch.core.job.builder

Class FlowBuilder<Q>

java.lang.Object

org.springframework.batch.core.job.builder.FlowBuilder<Q>

Type Parameters:

Q - the type of object returned by the builder (by default a Flow)

Direct Known Subclasses:

JobFlowBuilder

public class FlowBuilder<Q>
extends Object

A builder for a flow of steps that can be executed as a job or as part of a job. Steps can be linked together with conditional transitions that depend on the exit status of the previous step.

Since:

2.2

Author:

Dave Syer

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FlowBuilder.SplitBuilder<Q> A builder for building a split state.
static class	FlowBuilder.TransitionBuilder<Q> A builder for transitions within a flow.
static class	FlowBuilder.UnterminatedFlowBuilder<Q> A builder for continuing a flow from a decision state.

Constructor Summary

Constructors

Constructor and Description
FlowBuilder(String name)

Method Summary

Methods

Modifier and Type	Method and Description
Q	build() Validate the current state of the builder and build a flow.
Q	end() A synonym for build() which callers might find useful.
protected Flow	flow()
FlowBuilder<Q>	from(Flow flow) Start again from a subflow that was already registered.
FlowBuilder.UnterminatedFlowBuilder<Q>	from(JobExecutionDecider decider) Start again from a decision that was already registered.
FlowBuilder<Q>	from(Step step) Go back to a previously registered step and start a new path.
FlowBuilder<Q>	next(Flow flow) Go next on successful completion to a subflow.
FlowBuilder.UnterminatedFlowBuilder<Q>	next(JobExecutionDecider decider) Transition to the decider on successful completion of the current step.
FlowBuilder<Q>	next(Step step) Transition to the next step on successful completion of the current step.
FlowBuilder.TransitionBuilder<Q>	on(String pattern) Start a transition to a new state if the exit status from the previous state matches the pattern given.
FlowBuilder.SplitBuilder<Q>	split(org.springframework.core.task.TaskExecutor executor)
FlowBuilder<Q>	start(Flow flow) If a flow should start with a subflow use this as the first state.
FlowBuilder.UnterminatedFlowBuilder<Q>	start(JobExecutionDecider decider) If a flow should start with a decision use this as the first state.
FlowBuilder<Q>	start(Step step) Start a flow.

Methods inherited from class java.lang.Object

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

Constructor Detail

FlowBuilder

public FlowBuilder(String name)

Method Detail

build

public Q build()

Validate the current state of the builder and build a flow. Subclasses may override this to build an object of a different type that itself depends on the flow.

Returns:

a flow

next

public FlowBuilder<Q> next(Step step)

Transition to the next step on successful completion of the current step. All other outcomes are treated as failures.

Parameters:

step - the next step

Returns:

this to enable chaining

start

public FlowBuilder<Q> start(Step step)

Start a flow. If some steps are already registered, just a synonym for from(Step).

Parameters:

step - the step to start with

Returns:

this to enable chaining

from

public FlowBuilder<Q> from(Step step)

Go back to a previously registered step and start a new path. If no steps are registered yet just a synonym for start(Step).

Parameters:

step - the step to start from (already registered)

Returns:

this to enable chaining

next

public FlowBuilder.UnterminatedFlowBuilder<Q> next(JobExecutionDecider decider)

Transition to the decider on successful completion of the current step. All other outcomes are treated as failures.

Parameters:

decider - the JobExecutionDecider to determine the next step to execute

Returns:

this to enable chaining

start

public FlowBuilder.UnterminatedFlowBuilder<Q> start(JobExecutionDecider decider)

If a flow should start with a decision use this as the first state.

Parameters:

decider - the to start from

Returns:

a builder to enable chaining

from

public FlowBuilder.UnterminatedFlowBuilder<Q> from(JobExecutionDecider decider)

Start again from a decision that was already registered.

Parameters:

decider - the decider to start from (already registered)

Returns:

a builder to enable chaining

next

public FlowBuilder<Q> next(Flow flow)

Go next on successful completion to a subflow.

Parameters:

flow - the flow to go to

Returns:

a builder to enable chaining

from

public FlowBuilder<Q> from(Flow flow)

Start again from a subflow that was already registered.

Parameters:

flow - the flow to start from (already registered)

Returns:

a builder to enable chaining

start

public FlowBuilder<Q> start(Flow flow)

If a flow should start with a subflow use this as the first state.

Parameters:

flow - the flow to start from

Returns:

a builder to enable chaining

split

public FlowBuilder.SplitBuilder<Q> split(org.springframework.core.task.TaskExecutor executor)

Parameters:

executor - a task executor to execute the split flows

Returns:

a builder to enable fluent chaining

on

public FlowBuilder.TransitionBuilder<Q> on(String pattern)

Start a transition to a new state if the exit status from the previous state matches the pattern given. Successful completion normally results in an exit status equal to (or starting with by convention) "COMPLETED". See ExitStatus for commonly used values.

Parameters:

pattern - the pattern of exit status on which to take this transition

Returns:

a builder to enable fluent chaining

end

public final Q end()

A synonym for build() which callers might find useful. Subclasses can override build to create an object of the desired type (e.g. a parent builder or an actual flow).

Returns:

the result of the builder

flow

protected Flow flow()