org.apache.mahout.cf.taste.example.grouplens.BooleanDataAndDateDataModel.java Source code

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Here is the source code for org.apache.mahout.cf.taste.example.grouplens.BooleanDataAndDateDataModel.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.mahout.cf.taste.example.grouplens;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.net.URL;
import java.util.regex.Pattern;

import com.google.common.base.Charsets;
import com.google.common.io.Closeables;
import com.google.common.io.Files;
import com.google.common.io.InputSupplier;
import com.google.common.io.Resources;
import org.apache.mahout.cf.taste.impl.model.file.FileDataModel;
import org.apache.mahout.common.iterator.FileLineIterable;

public final class BooleanDataAndDateDataModel extends FileDataModel {

    private static final String COLON_DELIMTER = "::";
    private static final Pattern COLON_DELIMITER_PATTERN = Pattern.compile(COLON_DELIMTER);

    public BooleanDataAndDateDataModel() throws IOException {
        this(readResourceToTempFile(
                "/Users/josephmisiti/mathandpencil/projects/hadoop/mahout/example1/ml-10M100K/ratings.dat"));
    }

    /**
     * @param ratingsFile GroupLens ratings.dat file in its native format
     * @throws IOException if an error occurs while reading or writing files
     */
    public BooleanDataAndDateDataModel(File ratingsFile) throws IOException {
        super(convertGLFile(ratingsFile));
    }

    private static File convertGLFile(File originalFile) throws IOException {
        // Now translate the file; remove commas, then convert "::" delimiter to comma
        File resultFile = new File(new File(System.getProperty("java.io.tmpdir")), "ratings.txt");
        if (resultFile.exists()) {
            resultFile.delete();
        }
        Writer writer = null;
        try {
            writer = new OutputStreamWriter(new FileOutputStream(resultFile), Charsets.UTF_8);
            for (String line : new FileLineIterable(originalFile, false)) {
                int lastDelimiterStart = line.lastIndexOf(COLON_DELIMTER);
                if (lastDelimiterStart < 0) {
                    throw new IOException("Unexpected input format on line: " + line);
                }
                String subLine = line.substring(0, lastDelimiterStart);
                String convertedLine = COLON_DELIMITER_PATTERN.matcher(subLine).replaceAll(",");
                writer.write(convertedLine);
                writer.write('\n');
            }
        } catch (IOException ioe) {
            resultFile.delete();
            throw ioe;
        } finally {
            Closeables.closeQuietly(writer);
        }
        return resultFile;
    }

    public static File readResourceToTempFile(String resourceName) throws IOException {
        InputSupplier<? extends InputStream> inSupplier;
        try {
            URL resourceURL = Resources.getResource(GroupLensRecommender.class, resourceName);
            inSupplier = Resources.newInputStreamSupplier(resourceURL);
        } catch (IllegalArgumentException iae) {
            File resourceFile = new File(resourceName);
            inSupplier = Files.newInputStreamSupplier(resourceFile);
        }
        File tempFile = File.createTempFile("taste", null);
        tempFile.deleteOnExit();
        Files.copy(inSupplier, tempFile);
        return tempFile;
    }

    @Override
    public String toString() {
        return "BooleanDataAndDateDataModel";
    }

}