/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.uima.analysis_engine.impl;
import org.apache.uima.analysis_engine.AnalysisEngineProcessException;
import org.apache.uima.analysis_engine.metadata.FixedFlow;
import org.apache.uima.analysis_engine.metadata.FlowConstraints;
import org.apache.uima.cas.CAS;
import org.apache.uima.flow.CasFlowController_ImplBase;
import org.apache.uima.flow.CasFlow_ImplBase;
import org.apache.uima.flow.FinalStep;
import org.apache.uima.flow.Flow;
import org.apache.uima.flow.FlowControllerContext;
import org.apache.uima.flow.SimpleStep;
import org.apache.uima.flow.Step;
import org.apache.uima.resource.ResourceInitializationException;
/**
* Test FlowController that drops any segment whose document text is "DROP". Otherwise uses linear
* flow.
*/
public class SegmentDroppingFlowController extends CasFlowController_ImplBase {
String[] mSequence;
public void initialize(FlowControllerContext aContext) throws ResourceInitializationException {
super.initialize(aContext);
FlowConstraints flowConstraints = aContext.getAggregateMetadata().getFlowConstraints();
mSequence = ((FixedFlow) flowConstraints).getFixedFlow();
}
/*
* (non-Javadoc)
*
* @see org.apache.uima.flow.CasFlowController_ImplBase#computeFlow(org.apache.uima.cas.CAS)
*/
public Flow computeFlow(CAS aCAS) throws AnalysisEngineProcessException {
FixedFlowObject ffo = new FixedFlowObject(aCAS, 0);
ffo.setCas(aCAS);
return ffo;
}
class FixedFlowObject extends CasFlow_ImplBase {
private int currentStep;
private boolean wasSegmented = false;
/**
* Create a new fixed flow starting at step <code>startStep</code> of the fixed sequence.
*
* @param cas
* aCAS
*
* @param startStep
* index of mSequence to start at
*/
public FixedFlowObject(CAS cas, int startStep) {
setCas(cas);
currentStep = startStep;
}
/*
* (non-Javadoc)
*
* @see org.apache.uima.flow.Flow#next()
*/
public Step next() throws AnalysisEngineProcessException {
// drop any segment whose document text is "DROP"
if ("DROP".equals(getCas().getCurrentView().getDocumentText())) {
return new FinalStep(true);
}
if (currentStep >= mSequence.length) {
return new FinalStep(); // this CAS has finished the sequence
}
// If CAS was segmented, do not continue with flow. The individual segments
// are processed further but the original CAS is not.
if (wasSegmented) {
return new FinalStep();
}
// otherwise, we just send the CAS to the next AE in sequence.
return new SimpleStep(mSequence[currentStep++]);
}
/*
* (non-Javadoc)
*
* @see org.apache.uima.flow.CasFlow_ImplBase#newCasProduced(CAS, String)
*/
public Flow newCasProduced(CAS newCas, String producedBy) throws AnalysisEngineProcessException {
// record that the input CAS has been segmented (affects its subsequent flow)
wasSegmented = true;
// start the new segment CAS from the next node after the Segmenter that produced it
int i = 0;
while (!mSequence[i].equals(producedBy))
i++;
return new FixedFlowObject(newCas, i + 1);
}
}
}