org.apache.solr.handler.clustering.carrot2.EchoTokensClusteringAlgorithm.java Source code

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Here is the source code for org.apache.solr.handler.clustering.carrot2.EchoTokensClusteringAlgorithm.java

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/*
 * 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.solr.handler.clustering.carrot2;

import java.util.List;

import org.carrot2.core.Cluster;
import org.carrot2.core.Document;
import org.carrot2.core.IClusteringAlgorithm;
import org.carrot2.core.LanguageCode;
import org.carrot2.core.ProcessingComponentBase;
import org.carrot2.core.ProcessingException;
import org.carrot2.core.attribute.AttributeNames;
import org.carrot2.core.attribute.Processing;
import org.carrot2.text.preprocessing.PreprocessingContext;
import org.carrot2.text.preprocessing.pipeline.BasicPreprocessingPipeline;
import org.carrot2.util.attribute.Attribute;
import org.carrot2.util.attribute.Bindable;
import org.carrot2.util.attribute.Input;
import org.carrot2.util.attribute.Output;

import com.google.common.collect.Lists;

/**
 * A mock Carrot2 clustering algorithm that outputs each token of each document
 * as a separate cluster. Useful only in tests.
 */
@Bindable(prefix = "EchoTokensClusteringAlgorithm")
public class EchoTokensClusteringAlgorithm extends ProcessingComponentBase implements IClusteringAlgorithm {
    @Input
    @Processing
    @Attribute(key = AttributeNames.DOCUMENTS)
    public List<Document> documents;

    @Output
    @Processing
    @Attribute(key = AttributeNames.CLUSTERS)
    public List<Cluster> clusters;

    public BasicPreprocessingPipeline preprocessing = new BasicPreprocessingPipeline();

    @Override
    public void process() throws ProcessingException {
        final PreprocessingContext preprocessingContext = preprocessing.preprocess(documents, "",
                LanguageCode.ENGLISH);
        clusters = Lists.newArrayListWithCapacity(preprocessingContext.allTokens.image.length);
        for (char[] token : preprocessingContext.allTokens.image) {
            if (token != null) {
                clusters.add(new Cluster(new String(token)));
            }
        }
    }
}