CqpContextProvider.java

/*******************************************************************************
 * Copyright 2013
 * Ubiquitous Knowledge Processing (UKP) Lab
 * Technische Universität Darmstadt
 * 
 * Licensed 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 de.tudarmstadt.ukp.csniper.webapp.search.cqp;

import java.util.List;

import org.apache.commons.lang.StringUtils;

import de.tudarmstadt.ukp.csniper.webapp.evaluation.model.EvaluationItem;
import de.tudarmstadt.ukp.csniper.webapp.evaluation.model.ItemContext;
import de.tudarmstadt.ukp.csniper.webapp.search.ContextProvider;
import de.tudarmstadt.ukp.csniper.webapp.search.CorpusService;

public class CqpContextProvider
	implements ContextProvider
{
	private CqpEngine engine;

	public void setEngine(CqpEngine aEngine)
	{
		engine = aEngine;
	}

	public CqpEngine getEngine()
	{
		return engine;
	}

	@Override
	public ItemContext getContext(EvaluationItem aItem, int aLeftSize, int aRightSize)
	{
		StringBuilder[] sb = { new StringBuilder(), new StringBuilder() };
		int idx = 0;

		int contextWidth = 1;
		CqpQuery cqpManager = new CqpQuery(engine, aItem.getType(), aItem.getCollectionId());
		List<String> output = cqpManager.getContextAround(aItem, contextWidth);

		String[] context = StringUtils
				.substringsBetween(output.get(0), "<sentence>", "</sentence>");

		if (context.length < 1 + 2 * contextWidth) {
			// this method of extracting the context is not error prone
			// TODO find a better one...
			for (int i = 0; i < context.length; i++) {
				if (context[i].equals(aItem.getCoveredText())) {
					idx = 1;
				}
				else {
					sb[idx].append(context[i] + " ");
				}
			}
		}
		else {
			// this can only be used when we have full context
			for (int i = 0; i < (context.length - 1) / 2; i++) {
				sb[0].append(context[i] + " ");
				sb[1].append(context[i + (context.length - 1) / 2 + 1] + " ");
			}
		}

		return null;
//		return new String[] { sb[0].toString(), sb[1].toString() };
	}

	@Override
	public void setOutputPos(boolean aShowPos)
	{
		throw new UnsupportedOperationException();
	}

	@Override
	public void setCorpusService(CorpusService aCorpusService)
	{
		throw new UnsupportedOperationException();
	}
}