com.cloudera.knittingboar.utils.DataUtils.java Source code

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Here is the source code for com.cloudera.knittingboar.utils.DataUtils.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 com.cloudera.knittingboar.utils;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;

import org.apache.commons.io.FileUtils;

public class DataUtils {

    private static File twentyNewsGroups;
    private static final String TWENTY_NEWS_GROUP_LOCAL_DIR = "knittingboar-20news";
    private static final String TWENTY_NEWS_GROUP_TAR_URL = "http://people.csail.mit.edu/jrennie/20Newsgroups/20news-bydate.tar.gz";
    private static final String TWENTY_NEWS_GROUP_TAR_FILE_NAME = "20news-bydate.tar.gz";

    public static synchronized File getTwentyNewsGroupDir() throws IOException {
        if (twentyNewsGroups != null) {
            return twentyNewsGroups;
        }
        // mac gives unique tmp each run and we want to store this persist
        // this data across restarts
        File tmpDir = new File("/tmp");
        if (!tmpDir.isDirectory()) {
            tmpDir = new File(System.getProperty("java.io.tmpdir"));
        }
        File baseDir = new File(tmpDir, TWENTY_NEWS_GROUP_LOCAL_DIR);
        if (!(baseDir.isDirectory() || baseDir.mkdir())) {
            throw new IOException("Could not mkdir " + baseDir);
        }
        File tarFile = new File(baseDir, TWENTY_NEWS_GROUP_TAR_FILE_NAME);

        if (!tarFile.isFile()) {
            FileUtils.copyURLToFile(new URL(TWENTY_NEWS_GROUP_TAR_URL), tarFile);
        }

        Process p = Runtime.getRuntime()
                .exec(String.format("tar -C %s -xvf %s", baseDir.getAbsolutePath(), tarFile.getAbsolutePath()));
        BufferedReader stdError = new BufferedReader(new InputStreamReader(p.getErrorStream()));
        System.out.println("Here is the standard error of the command (if any):\n");
        String s;
        while ((s = stdError.readLine()) != null) {
            System.out.println(s);
        }
        stdError.close();
        twentyNewsGroups = baseDir;
        return twentyNewsGroups;
    }
}