org.apache.uima.flow

Class JCasFlowController_ImplBase

java.lang.Object

org.apache.uima.flow.FlowController_ImplBase

org.apache.uima.flow.JCasFlowController_ImplBase

All Implemented Interfaces:

FlowController

public abstract class JCasFlowController_ImplBase
extends FlowController_ImplBase

Base class to be extended by FlowControllers that use the JCas interface.

Constructor Summary

Constructors

Constructor and Description
JCasFlowController_ImplBase()

Method Summary

Modifier and Type	Method and Description
Flow	computeFlow(AbstractCas aCAS) Overriden to check that aCAS is an instanceof JCas.
abstract Flow	computeFlow(JCas aJCas) This method must be overriden by subclasses.
Class<JCas>	getRequiredCasInterface() Returns the specific CAS interface that this FlowController requires the framework to pass to its FlowController.computeFlow(AbstractCas) method.

Methods inherited from class org.apache.uima.flow.FlowController_ImplBase

addAnalysisEngines, batchProcessComplete, collectionProcessComplete, destroy, getContext, initialize, reconfigure, removeAnalysisEngines

Methods inherited from class java.lang.Object

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

Constructor Detail

JCasFlowController_ImplBase

public JCasFlowController_ImplBase()

Method Detail

getRequiredCasInterface

public Class<JCas> getRequiredCasInterface()

Description copied from interface: FlowController

Returns the specific CAS interface that this FlowController requires the framework to pass to its FlowController.computeFlow(AbstractCas) method.

Returns:

the required CAS interface. This must specify a subtype of AbstractCas.

computeFlow

public final Flow computeFlow(AbstractCas aCAS)
                       throws AnalysisEngineProcessException

Overriden to check that aCAS is an instanceof JCas. If it is, then computeFlow(JCas) is called. If not, an exception is thrown.

Parameters:

aCAS - A CAS that this FlowController should process. The framework will ensure that aCAS implements the specific CAS interface declared in the <casInterface> element of this FlowController's descriptor.

Returns:

a Flow object that has responsibility for routing aCAS through the Aggregate Analysis Engine.

Throws:

AnalysisEngineProcessException - if this FlowController encounters a problem computing the flow for the CAS

computeFlow

public abstract Flow computeFlow(JCas aJCas)
                          throws AnalysisEngineProcessException

This method must be overriden by subclasses. It takes a JCas and returns a Flow object that is responsible for routing this particular JCas through the components of this Aggregate. The Flow object should be given a handle to the JCas, so that it can use information in the CAS to make routing decisions.

FlowController implementations will typically define their own class that implements Flow by extending from the base class JCasFlow_ImplBase. This method would then just instantiate the flow object, call its setCas method to provide a handle to the JCas, and return the flow object.

Parameters:

aJCas - the JCas to be routed

Returns:

a Flow object that will be used to route aJCas

Throws:

AnalysisEngineProcessException - if a problem occurs during processing

See Also:

FlowController.computeFlow(AbstractCas)