Package org.apache.uima.flow

Class CasFlowController_ImplBase

    • Constructor Detail

      • CasFlowController_ImplBase

        public CasFlowController_ImplBase()

    • Method Detail

      • getRequiredCasInterface

        public java.lang.Class<CAS> 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 CAS. If it is, then computeFlow(CAS) 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
        See Also:
        FlowController.computeFlow(AbstractCas)

      • computeFlow

        public abstract Flow computeFlow​(CAS aCAS)
                          throws AnalysisEngineProcessException
        This method must be overriden by subclasses. It takes a CAS and returns a Flow object that is responsible for routing this particular CAS through the components of this Aggregate. The Flow object should be given a handle to the CAS, 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 CasFlow_ImplBase. This method would then just instantiate the flow object, call its setCas method to provide a handle to the CAS, and return the flow object.

        Parameters:
        aCAS - the CAS to be routed
        Returns:
        a Flow object that will be used to route aCAS
        Throws:
        AnalysisEngineProcessException - if a problem occurs during processing
        See Also:
        FlowController.computeFlow(AbstractCas)

      • typeSystemInit

        public void typeSystemInit​(TypeSystem aTypeSystem)
                    throws AnalysisEngineProcessException
        This method may be overriden by subclasses. It is called whenever th TypeSystem of the CAS changes. This method will be called immediately prior to the first call to computeFlow(CAS), and will be called again whenever the CAS TypeSystem changes.

        In this method, the FlowController can use the TypeSystem to resolve the names of Type and Features to the actual Type and Feature objects, which can then be used to access information from the CAS during routing.

        Parameters:
        aTypeSystem - the typesystem
        Throws:
        AnalysisEngineProcessException - if a problem occurs during processing