com.streamsets.datacollector.util.UntarUtility.java Source code

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Here is the source code for com.streamsets.datacollector.util.UntarUtility.java

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/**
 * Copyright 2015 StreamSets Inc.
 *
 * Licensed under 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.streamsets.datacollector.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.LinkedList;
import java.util.List;
import java.util.zip.GZIPInputStream;

import org.apache.commons.compress.archivers.ArchiveException;
import org.apache.commons.compress.archivers.ArchiveStreamFactory;
import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class UntarUtility {
    private static final Logger LOG = LoggerFactory.getLogger(UntarUtility.class);

    /**
     * Untar an input file into an output file. The output file is created in the output folder, having the same name as
     * the input file, minus the '.tar' extension.
     * @param inputFile the input .tar file
     * @param outputDir the output directory file.
     * @throws IOException
     * @throws FileNotFoundException
     * @return The {@link List} of {@link File}s with the untared content.
     * @throws ArchiveException
     */
    private static List<File> unTar(final File inputFile, final File outputDir)
            throws FileNotFoundException, IOException, ArchiveException {

        LOG.info(String.format("Untaring %s to dir %s.", inputFile.getAbsolutePath(), outputDir.getAbsolutePath()));

        final List<File> untaredFiles = new LinkedList<File>();
        final InputStream is = new FileInputStream(inputFile);
        final TarArchiveInputStream debInputStream = (TarArchiveInputStream) new ArchiveStreamFactory()
                .createArchiveInputStream("tar", is);
        TarArchiveEntry entry = null;
        while ((entry = (TarArchiveEntry) debInputStream.getNextEntry()) != null) {
            final File outputFile = new File(outputDir, entry.getName());
            if (entry.isDirectory()) {
                LOG.info(String.format("Attempting to write output directory %s.", outputFile.getAbsolutePath()));
                if (!outputFile.exists()) {
                    LOG.info(String.format("Attempting to create output directory %s.",
                            outputFile.getAbsolutePath()));
                    if (!outputFile.mkdirs()) {
                        throw new IllegalStateException(
                                String.format("Couldn't create directory %s.", outputFile.getAbsolutePath()));
                    }
                }
            } else {
                LOG.info(String.format("Creating output file %s.", outputFile.getAbsolutePath()));
                final OutputStream outputFileStream = new FileOutputStream(outputFile);
                IOUtils.copy(debInputStream, outputFileStream);
                outputFileStream.close();
            }
            untaredFiles.add(outputFile);
        }
        debInputStream.close();

        return untaredFiles;
    }

    /**
     * Ungzip an input file into an output file.
     * <p>
     * The output file is created in the output folder, having the same name as the input file, minus the '.gz' extension.
     * @param inputFile the input .gz file
     * @param outputDir the output directory file.
     * @throws IOException
     * @throws FileNotFoundException
     * @return The {@File} with the ungzipped content.
     * @throws ArchiveException
     */
    public static List<File> unGzip(final File inputFile, final File outputDir)
            throws FileNotFoundException, IOException, ArchiveException {
        LOG.info(String.format("Ungzipping %s to dir %s.", inputFile.getAbsolutePath(),
                outputDir.getAbsolutePath()));

        final File outputFile = new File(outputDir,
                inputFile.getName().substring(0, inputFile.getName().length() - 3));

        final GZIPInputStream in = new GZIPInputStream(new FileInputStream(inputFile));
        final FileOutputStream out = new FileOutputStream(outputFile);

        IOUtils.copy(in, out);

        in.close();
        out.close();

        return unTar(outputFile, outputDir);
    }
}