com.meizu.nlp.classification.utils.DataSplitterTest.java Source code

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Here is the source code for com.meizu.nlp.classification.utils.DataSplitterTest.java

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package com.meizu.nlp.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.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.*;
import org.apache.lucene.store.BaseDirectoryWrapper;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.LuceneTestCase;
import org.apache.lucene.util.TestUtil;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.util.Random;

public class DataSplitterTest extends LuceneTestCase {

    private LeafReader originalIndex;
    private RandomIndexWriter indexWriter;
    private Directory dir;

    private String textFieldName = "text";
    private String classFieldName = "class";
    private String idFieldName = "id";

    @Override
    @Before
    public void setUp() throws Exception {
        super.setUp();
        dir = newDirectory();
        indexWriter = new RandomIndexWriter(random(), dir);

        FieldType ft = new FieldType(TextField.TYPE_STORED);
        ft.setStoreTermVectors(true);
        ft.setStoreTermVectorOffsets(true);
        ft.setStoreTermVectorPositions(true);

        Document doc;
        Random rnd = random();
        for (int i = 0; i < 100; i++) {
            doc = new Document();
            doc.add(new Field(idFieldName, Integer.toString(i), ft));
            doc.add(new Field(textFieldName, TestUtil.randomUnicodeString(rnd, 1024), ft));
            doc.add(new Field(classFieldName, TestUtil.randomUnicodeString(rnd, 10), ft));
            indexWriter.addDocument(doc);
        }

        indexWriter.commit();

        originalIndex = SlowCompositeReaderWrapper.wrap(indexWriter.getReader());

    }

    @Override
    @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(LeafReader 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 {
            if (trainingIndex != null) {
                trainingIndex.close();
            }
            if (testIndex != null) {
                testIndex.close();
            }
            if (crossValidationIndex != null) {
                crossValidationIndex.close();
            }
        }
    }

    private static void closeQuietly(IndexReader reader) throws IOException {
        try {
            if (reader != null)
                reader.close();
        } catch (Exception e) {
            // do nothing
        }
    }
}