lucene/classification/src/test/org/apache/lucene/classification/document/TestKNearestNeighborDocumentClassifier.java

/*
 * 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.lucene.classification.document;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.util.BytesRef;
import org.junit.Test;

/** Tests for {@link org.apache.lucene.classification.KNearestNeighborClassifier} */
public class TestKNearestNeighborDocumentClassifier
    extends DocumentClassificationTestBase<BytesRef> {

  @Test
  public void testBasicDocumentClassification() throws Exception {
    try {
      Document videoGameDocument = getVideoGameDocument();
      Document batmanDocument = getBatmanDocument();
      KNearestNeighborDocumentClassifier classifier =
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              null,
              1,
              4,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName, titleFieldName, authorFieldName});
      checkCorrectDocumentClassification(classifier, videoGameDocument, VIDEOGAME_RESULT);
      checkCorrectDocumentClassification(classifier, batmanDocument, BATMAN_RESULT);
      // considering only the text we have wrong classification because the text was ambiguos on
      // purpose
      checkCorrectDocumentClassification(
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              null,
              1,
              1,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName}),
          videoGameDocument,
          BATMAN_RESULT);
      checkCorrectDocumentClassification(
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              null,
              1,
              1,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName}),
          batmanDocument,
          VIDEOGAME_RESULT);

    } finally {
      if (indexReader != null) {
        indexReader.close();
      }
    }
  }

  @Test
  public void testBasicDocumentClassificationScore() throws Exception {
    try {
      Document videoGameDocument = getVideoGameDocument();
      Document batmanDocument = getBatmanDocument();
      KNearestNeighborDocumentClassifier classifier =
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              null,
              1,
              4,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName, titleFieldName, authorFieldName});
      double score1 =
          checkCorrectDocumentClassification(classifier, videoGameDocument, VIDEOGAME_RESULT);
      assertEquals(1.0, score1, 0);
      double score2 = checkCorrectDocumentClassification(classifier, batmanDocument, BATMAN_RESULT);
      assertEquals(1.0, score2, 0);
      // considering only the text we have wrong classification because the text was ambiguos on
      // purpose
      double score3 =
          checkCorrectDocumentClassification(
              new KNearestNeighborDocumentClassifier(
                  indexReader,
                  null,
                  null,
                  1,
                  1,
                  1,
                  categoryFieldName,
                  field2analyzer,
                  new String[] {textFieldName}),
              videoGameDocument,
              BATMAN_RESULT);
      assertEquals(1.0, score3, 0);
      double score4 =
          checkCorrectDocumentClassification(
              new KNearestNeighborDocumentClassifier(
                  indexReader,
                  null,
                  null,
                  1,
                  1,
                  1,
                  categoryFieldName,
                  field2analyzer,
                  new String[] {textFieldName}),
              batmanDocument,
              VIDEOGAME_RESULT);
      assertEquals(1.0, score4, 0);
    } finally {
      if (indexReader != null) {
        indexReader.close();
      }
    }
  }

  @Test
  public void testBoostedDocumentClassification() throws Exception {
    try {
      checkCorrectDocumentClassification(
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              null,
              1,
              1,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName, titleFieldName + "^100", authorFieldName}),
          getBatmanAmbiguosDocument(),
          BATMAN_RESULT);
      // considering without boost wrong classification will appear
      checkCorrectDocumentClassification(
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              null,
              1,
              1,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName, titleFieldName, authorFieldName}),
          getBatmanAmbiguosDocument(),
          VIDEOGAME_RESULT);
    } finally {
      if (indexReader != null) {
        indexReader.close();
      }
    }
  }

  @Test
  public void testBasicDocumentClassificationWithQuery() throws Exception {
    try {
      TermQuery query = new TermQuery(new Term(authorFieldName, "ign"));
      checkCorrectDocumentClassification(
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              query,
              1,
              1,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName, titleFieldName, authorFieldName}),
          getVideoGameDocument(),
          VIDEOGAME_RESULT);
      checkCorrectDocumentClassification(
          new KNearestNeighborDocumentClassifier(
              indexReader,
              null,
              query,
              1,
              1,
              1,
              categoryFieldName,
              field2analyzer,
              new String[] {textFieldName, titleFieldName, authorFieldName}),
          getBatmanDocument(),
          VIDEOGAME_RESULT);
    } finally {
      if (indexReader != null) {
        indexReader.close();
      }
    }
  }
}