Package org.springframework.batch.core.job.flow.support

Class SimpleFlow

java.lang.Object

org.springframework.batch.core.job.flow.support.SimpleFlow

All Implemented Interfaces:

Flow, org.springframework.beans.factory.InitializingBean

public class SimpleFlow
extends Object
implements Flow, org.springframework.beans.factory.InitializingBean

A Flow that branches conditionally depending on the exit status of the last State. The input parameters are the state transitions (in no particular order). The start state name can be specified explicitly (and must exist in the set of transitions), or computed from the existing transitions, if unambiguous.

Since:

2.0

Author:

Dave Syer, Michael Minella, Mahmoud Ben Hassine, Taeik Lim

Constructor Summary

Constructors

Constructor	Description
SimpleFlow(String name)	Create a flow with the given name.

Method Summary

Modifier and Type	Method	Description
void	afterPropertiesSet()	Locate start state and pre-populate data structures needed for execution.
String	getName()	Get the name for this flow.
State	getStartState()
State	getState(String stateName)	Retrieve the State with the given name.
protected Map<String,State>	getStateMap()
Collection<State>	getStates()	Convenient accessor for clients needing to explore the states of this flow.
protected Map<String,Set<StateTransition>>	getTransitionMap()
protected boolean	isFlowContinued(State state, FlowExecutionStatus status, StepExecution stepExecution)
protected State	nextState(String stateName, FlowExecutionStatus status, StepExecution stepExecution)
FlowExecution	resume(String stateName, FlowExecutor executor)
void	setStateTransitionComparator(Comparator<StateTransition> stateTransitionComparator)
void	setStateTransitions(List<StateTransition> stateTransitions)	Public setter for the stateTransitions.
FlowExecution	start(FlowExecutor executor)

Methods inherited from class java.lang.Object

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

Constructor Details

SimpleFlow

public SimpleFlow(String name)

Create a flow with the given name.

Parameters:

name - the name of the flow

Method Details

setStateTransitionComparator

public void setStateTransitionComparator(Comparator<StateTransition> stateTransitionComparator)

getStartState

public State getStartState()

getName

public String getName()

Get the name for this flow.

Specified by:

getName in interface Flow

Returns:

the name of the flow

See Also:

• Flow.getName()

setStateTransitions

public void setStateTransitions(List<StateTransition> stateTransitions)

Public setter for the stateTransitions.

Parameters:

stateTransitions - the stateTransitions to set

getState

public State getState(String stateName)

Retrieve the State with the given name. If there is no State with the given name, then return null.

Specified by:

getState in interface Flow

Parameters:

stateName - the name of the state to retrieve

Returns:

the State

getStates

public Collection<State> getStates()

Convenient accessor for clients needing to explore the states of this flow.

Specified by:

getStates in interface Flow

Returns:

the states

afterPropertiesSet

public void afterPropertiesSet()
                        throws Exception

Locate start state and pre-populate data structures needed for execution.

Specified by:

afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean

Throws:

Exception

See Also:

• InitializingBean.afterPropertiesSet()

start

public FlowExecution start(FlowExecutor executor)
                    throws FlowExecutionException

Specified by:

start in interface Flow

Parameters:

executor - the FlowExecutor instance to use for the flow execution.

Returns:

a FlowExecution containing the exit status of the flow.

Throws:

FlowExecutionException - thrown if error occurs during flow execution.

See Also:

• Flow.start(FlowExecutor)

resume

public FlowExecution resume(String stateName,
 FlowExecutor executor)
                     throws FlowExecutionException

Specified by:

resume in interface Flow

Parameters:

stateName - the name of the state to resume on.

executor - the context to be passed into each state executed.

Returns:

a FlowExecution containing the exit status of the flow.

Throws:

FlowExecutionException - thrown if error occurs during flow execution.

See Also:

• Flow.resume(String, FlowExecutor)

getTransitionMap

protected Map<String,Set<StateTransition>> getTransitionMap()

getStateMap

protected Map<String,State> getStateMap()

nextState

protected State nextState(String stateName,
 FlowExecutionStatus status,
 StepExecution stepExecution)
                   throws FlowExecutionException

Parameters:

stateName - the name of the next state.

status - FlowExecutionStatus instance.

stepExecution - StepExecution instance.

Returns:

the next Step (or null if this is the end)

Throws:

FlowExecutionException - thrown if error occurs during nextState processing.

isFlowContinued

protected boolean isFlowContinued(State state,
 FlowExecutionStatus status,
 StepExecution stepExecution)