package org.apache.lucene.classification.utils;
/*
* 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.
*/
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.MockAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.FieldType;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.AtomicReader;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.RandomIndexWriter;
import org.apache.lucene.index.SlowCompositeReaderWrapper;
import org.apache.lucene.store.BaseDirectoryWrapper;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.LuceneTestCase;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import java.io.IOException;
import java.util.Random;
/**
* Testcase for {@link org.apache.lucene.classification.utils.DatasetSplitter}
*/
public class DataSplitterTest extends LuceneTestCase {
private AtomicReader originalIndex;
private RandomIndexWriter indexWriter;
private Directory dir;
private String textFieldName = "text";
private String classFieldName = "class";
private String idFieldName = "id";
@Before
public void setUp() throws Exception {
super.setUp();
dir = newDirectory();
indexWriter = new RandomIndexWriter(random(), dir, new MockAnalyzer(random()));
FieldType ft = new FieldType(TextField.TYPE_STORED);
ft.setStoreTermVectors(true);
ft.setStoreTermVectorOffsets(true);
ft.setStoreTermVectorPositions(true);
Analyzer analyzer = new MockAnalyzer(random());
Document doc;
for (int i = 0; i < 100; i++) {
doc = new Document();
doc.add(new Field(idFieldName, random().toString(), ft));
doc.add(new Field(textFieldName, new StringBuilder(random().toString()).append(random().toString()).append(
random().toString()).toString(), ft));
doc.add(new Field(classFieldName, random().toString(), ft));
indexWriter.addDocument(doc, analyzer);
}
indexWriter.commit();
originalIndex = SlowCompositeReaderWrapper.wrap(indexWriter.getReader());
}
@After
public void tearDown() throws Exception {
originalIndex.close();
indexWriter.close();
dir.close();
super.tearDown();
}
@Test
public void testSplitOnAllFields() throws Exception {
assertSplit(originalIndex, 0.1, 0.1);
}
@Test
public void testSplitOnSomeFields() throws Exception {
assertSplit(originalIndex, 0.2, 0.35, idFieldName, textFieldName);
}
public static void assertSplit(AtomicReader originalIndex, double testRatio, double crossValidationRatio, String... fieldNames) throws Exception {
BaseDirectoryWrapper trainingIndex = newDirectory();
BaseDirectoryWrapper testIndex = newDirectory();
BaseDirectoryWrapper crossValidationIndex = newDirectory();
try {
DatasetSplitter datasetSplitter = new DatasetSplitter(testRatio, crossValidationRatio);
datasetSplitter.split(originalIndex, trainingIndex, testIndex, crossValidationIndex, new MockAnalyzer(random()), fieldNames);
assertNotNull(trainingIndex);
assertNotNull(testIndex);
assertNotNull(crossValidationIndex);
DirectoryReader trainingReader = DirectoryReader.open(trainingIndex);
assertTrue((int) (originalIndex.maxDoc() * (1d - testRatio - crossValidationRatio)) == trainingReader.maxDoc());
DirectoryReader testReader = DirectoryReader.open(testIndex);
assertTrue((int) (originalIndex.maxDoc() * testRatio) == testReader.maxDoc());
DirectoryReader cvReader = DirectoryReader.open(crossValidationIndex);
assertTrue((int) (originalIndex.maxDoc() * crossValidationRatio) == cvReader.maxDoc());
trainingReader.close();
testReader.close();
cvReader.close();
closeQuietly(trainingReader);
closeQuietly(testReader);
closeQuietly(cvReader);
} finally {
trainingIndex.close();
testIndex.close();
crossValidationIndex.close();
}
}
private static void closeQuietly(IndexReader reader) throws IOException {
try {
if (reader != null)
reader.close();
} catch (Exception e) {
// do nothing
}
}
}