AbstractStateMachine (Apache Commons SCXML 2.0-SNAPSHOT API)

java.lang.Object
- org.apache.commons.scxml2.env.AbstractStateMachine

```
public abstract class AbstractStateMachine
extends Object
```
This class demonstrates one approach for providing the base functionality needed by classes representing stateful entities, whose behaviors are defined via SCXML documents.

SCXML documents (more generically, UML state chart diagrams) can be used to define stateful behavior of objects, and Commons SCXML enables developers to use this model directly into the corresponding code artifacts. The resulting artifacts tend to be much simpler, embody a useful separation of concerns and are easier to understand and maintain. As the size of the modeled entity grows, these benefits become more apparent.

This approach functions by registering an SCXMLListener that gets notified onentry, and calls the namesake method for each state that has been entered.

This class swallows all exceptions only to log them. Developers of subclasses should think of themselves as "component developers" catering to other end users, and therefore ensure that the subclasses are free of ModelExceptions and the like. Most methods are protected for ease of subclassing.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected class AbstractStateMachine.EntryListener
A SCXMLListener that is only concerned about "onentry" notifications.

Nested Classes
Modifier and Type	Class and Description
`protected class`	`AbstractStateMachine.EntryListener` A SCXMLListener that is only concerned about "onentry" notifications.

Constructor Summary

Constructors
Constructor and Description
`AbstractStateMachine(SCXML stateMachine)` Convenience constructor.
`AbstractStateMachine(SCXML stateMachine, Context rootCtx, Evaluator evaluator)` Primary constructor.
`AbstractStateMachine(URL scxmlDocument)` Convenience constructor, object instantiation incurs parsing cost.
`AbstractStateMachine(URL scxmlDocument, Context rootCtx, Evaluator evaluator)` Primary constructor, object instantiation incurs parsing cost.

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`fireEvent(String event)` Fire an event on the SCXML engine.
`SCXMLExecutor`	`getEngine()` Get the SCXML engine driving the "lifecycle" of the instances of this class.
`org.apache.commons.logging.Log`	`getLog()` Get the log for this class.
`boolean`	`invoke(String methodName)` Invoke the no argument method with the following name.
`protected void`	`logError(Exception exception)` Utility method for logging error.
`boolean`	`resetMachine()` Reset the state machine.
`void`	`setLog(org.apache.commons.logging.Log log)` Set the log for this class.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - AbstractStateMachine
```
public AbstractStateMachine(URL scxmlDocument)
                     throws ModelException
```
    Convenience constructor, object instantiation incurs parsing cost.
    
    Parameters:
    scxmlDocument - The URL pointing to the SCXML document that describes the "lifecycle" of the instances of this class.
    
    Throws:
    
    ModelException
  - AbstractStateMachine
```
public AbstractStateMachine(URL scxmlDocument,
                    Context rootCtx,
                    Evaluator evaluator)
                     throws ModelException
```
    Primary constructor, object instantiation incurs parsing cost.
    
    Parameters:
    scxmlDocument - The URL pointing to the SCXML document that describes the "lifecycle" of the instances of this class.
    rootCtx - The root context for this instance.
    evaluator - The expression evaluator for this instance.
    
    Throws:
    
    ModelException
    See Also:
    Context, Evaluator
  - AbstractStateMachine
```
public AbstractStateMachine(SCXML stateMachine)
                     throws ModelException
```
    Convenience constructor.
    
    Parameters:
    stateMachine - The parsed SCXML instance that describes the "lifecycle" of the instances of this class.
    
    Throws:
    
    ModelException
    Since:
    
    0.7
  - AbstractStateMachine
```
public AbstractStateMachine(SCXML stateMachine,
                    Context rootCtx,
                    Evaluator evaluator)
                     throws ModelException
```
    Primary constructor.
    
    Parameters:
    stateMachine - The parsed SCXML instance that describes the "lifecycle" of the instances of this class.
    rootCtx - The root context for this instance.
    evaluator - The expression evaluator for this instance.
    
    Throws:
    
    ModelException
    Since:
    
    0.7
    
    See Also:
    Context, Evaluator
- Method Detail
  - fireEvent
```
public boolean fireEvent(String event)
```
    Fire an event on the SCXML engine.
    
    Parameters:
    event - The event name.
    
    Returns:
    Whether the state machine has reached a "final" configuration.
  - getEngine
```
public SCXMLExecutor getEngine()
```
    Get the SCXML engine driving the "lifecycle" of the instances of this class.
    
    Returns:
    Returns the engine.
  - getLog
```
public org.apache.commons.logging.Log getLog()
```
    Get the log for this class.
    
    Returns:
    Returns the log.
  - setLog
```
public void setLog(org.apache.commons.logging.Log log)
```
    Set the log for this class.
    
    Parameters:
    log - The log to set.
  - invoke
```
public boolean invoke(String methodName)
```
    Invoke the no argument method with the following name.
    
    Parameters:
    methodName - The method to invoke.
    
    Returns:
    Whether the invoke was successful.
  - resetMachine
```
public boolean resetMachine()
```
    Reset the state machine.
    
    Returns:
    Whether the reset was successful.
  - logError
```
protected void logError(Exception exception)
```
    Utility method for logging error.
    
    Parameters:
    exception - The exception leading to this error condition.

Class AbstractStateMachine

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

AbstractStateMachine

AbstractStateMachine

AbstractStateMachine

AbstractStateMachine

Method Detail

fireEvent

getEngine

getLog

setLog

invoke

resetMachine

logError