AbstractContentExtractor.java

//Dstl (c) Crown Copyright 2017
// Dstl (c) Crown Copyright 2017
package uk.gov.dstl.baleen.contentextractors.helpers;

import java.io.IOException;
import java.io.InputStream;
import java.util.Map;

import org.apache.uima.UimaContext;
import org.apache.uima.fit.component.initialize.ConfigurationParameterInitializer;
import org.apache.uima.jcas.JCas;
import org.apache.uima.jcas.tcas.DocumentAnnotation;
import org.apache.uima.resource.ResourceInitializationException;

import uk.gov.dstl.baleen.uima.BaleenContentExtractor;

/**
 * Provides a basis for content extractors, implementing common functionality.
 * 
 * Sets the source and timestamp of the document, and the extraction class as metadata.
 * 
 */
public abstract class AbstractContentExtractor extends BaleenContentExtractor {
	private static final String METADATA_KEY_CONTENT_EXTRACTOR = "baleen:content-extractor";

	@Override
	public void doProcessStream(InputStream stream, String source, JCas jCas) throws IOException {
		DocumentAnnotation doc = getSupport().getDocumentAnnotation(jCas);
		doc.setSourceUri(source);
		doc.setTimestamp(System.currentTimeMillis());

		// Add metadata item to capture which content extractor was used
		addMetadata(jCas, METADATA_KEY_CONTENT_EXTRACTOR, this.getClass().getName());
	}

	@Override
	public void doInitialize(UimaContext context, Map<String, Object> params) throws ResourceInitializationException {
		ConfigurationParameterInitializer.initialize(this, params);
	}

	@Override
	public void doDestroy() {
		// Do nothing
	}
}