org.terrier.structures.TestBasicLexiconEntry.java Source code

Introduction

Here is the source code for org.terrier.structures.TestBasicLexiconEntry.java

Source

/*
 * Terrier - Terabyte Retriever 
 * Webpage: http://terrier.org/
 * Contact: terrier{a.}dcs.gla.ac.uk
 * University of Glasgow - School of Computing Science
 * http://www.gla.ac.uk/
 * 
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is TestBasicLexiconEntry.java
 *
 * The Original Code is Copyright (C) 2004-2014 the University of Glasgow.
 * All Rights Reserved.
 *
 * Contributor(s):
 *   Craig Macdonald <craigm{a.}dcs.gla.ac.uk> (original contributor)
 */
package org.terrier.structures;

import static org.junit.Assert.assertEquals;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;

import org.apache.hadoop.io.Writable;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;

import org.terrier.structures.BasicLexiconEntry.Factory;

/** Tests that BasicLexiconEntry behaves as expected */
public class TestBasicLexiconEntry {

    @Rule
    public TemporaryFolder tmpfolder = new TemporaryFolder();

    @Test
    public void testBasic() throws Exception {
        BasicLexiconEntry le = new BasicLexiconEntry();
        //term id
        le.setTermId(1);
        assertEquals(le.getTermId(), 1);
        //position
        le.setOffset(0, (byte) 0);
        assertEquals(le.getOffset(), 0);
        assertEquals(le.getOffsetBits(), (byte) 0);

        le = new BasicLexiconEntry(2, 2, 5);
        assertEquals(le.getDocumentFrequency(), 2);
        assertEquals(le.getFrequency(), 5);
        le.add(new BasicLexiconEntry(0, 1, 10));
        assertEquals(le.getDocumentFrequency(), 3);
        assertEquals(le.getFrequency(), 15);
    }

    @Test
    public void testWritable() throws Exception {
        Factory f = new Factory();
        BasicLexiconEntry le = (BasicLexiconEntry) f.newInstance();
        le.setTermId(100);
        le.setOffset(10, (byte) 11);
        byte[] b = getBytes(le);
        System.err.println("le written in " + b.length + " bytes");
        assertEquals(b.length, f.getSize());
        BasicLexiconEntry leReader = (BasicLexiconEntry) f.newInstance();
        populateEntry(leReader, b);
        assertEquals(le.getTermId(), leReader.getTermId());
        assertEquals(le.getFrequency(), leReader.getFrequency());
        assertEquals(le.getDocumentFrequency(), leReader.getDocumentFrequency());
        assertEquals(le.getOffset(), leReader.getOffset());
        assertEquals(le.getOffsetBits(), leReader.getOffsetBits());
    }

    @Test
    public void testWritableFile() throws Exception {
        Factory f = new Factory();
        BasicLexiconEntry le = (BasicLexiconEntry) f.newInstance();
        le.setTermId(100);
        le.setOffset(10, (byte) 11);
        File tmpFile = tmpfolder.newFile("test.writable");
        DataOutputStream dos = new DataOutputStream(new FileOutputStream(tmpFile));
        le.write(dos);
        dos.close();
        BasicLexiconEntry leReader = (BasicLexiconEntry) f.newInstance();
        leReader.readFields(new DataInputStream(new FileInputStream(tmpFile)));
        assertEquals(le.getTermId(), leReader.getTermId());
        assertEquals(le.getFrequency(), leReader.getFrequency());
        assertEquals(le.getDocumentFrequency(), leReader.getDocumentFrequency());
        assertEquals(le.getOffset(), leReader.getOffset());
        assertEquals(le.getOffsetBits(), leReader.getOffsetBits());
    }

    static void populateEntry(LexiconEntry le, byte[] b) throws Exception {
        le.readFields(new DataInputStream(new ByteArrayInputStream(b)));
    }

    static byte[] getBytes(Writable w) throws Exception {
        ByteArrayOutputStream buffer = new ByteArrayOutputStream();
        DataOutputStream dos = new DataOutputStream(buffer);
        w.write(dos);
        return buffer.toByteArray();
    }
}