org.dataconservancy.ui.util.TarPackageExtractor.java Source code

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Here is the source code for org.dataconservancy.ui.util.TarPackageExtractor.java

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/*
 * Copyright 2012 Johns Hopkins University
 *
 * Licensed 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.dataconservancy.ui.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

import net.sourceforge.stripes.action.FileBean;

import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveInputStream;

import org.dataconservancy.ui.exceptions.UnpackException;

public class TarPackageExtractor extends BasePackageExtractor {

    /**
     * {@inheritDoc}
     */
    @Override
    protected List<File> unpackFilesFromArchive(File archive, String packageDir) throws Exception {
        FileInputStream fileStream = new FileInputStream(archive);
        TarArchiveInputStream tarInStream = new TarArchiveInputStream(fileStream);
        return unpackFilesFromStream(tarInStream, packageDir, archive.getName());
    }

    @Override
    protected List<File> unpackFilesFromStream(InputStream packageInputStream, String packageDir, String fileName)
            throws UnpackException {
        final TarArchiveInputStream tarInStream;

        if (!TarArchiveInputStream.class.isAssignableFrom(packageInputStream.getClass())) {
            tarInStream = new TarArchiveInputStream(packageInputStream);
        } else {
            tarInStream = (TarArchiveInputStream) packageInputStream;
        }

        List<File> files = new ArrayList<File>();
        try {
            TarArchiveEntry entry = tarInStream.getNextTarEntry();
            //Get next tar entry returns null when there are no more entries
            while (entry != null) {
                //Directories are automatically handled by the base class so we can ignore them in this class.
                if (!entry.isDirectory()) {
                    File entryFile = new File(packageDir, entry.getName());
                    if (entryFile != null) {
                        List<File> savedFiles = saveExtractedFile(entryFile, tarInStream);
                        files.addAll(savedFiles);
                    }
                }
                entry = tarInStream.getNextTarEntry();
            }

            tarInStream.close();
        } catch (IOException e) {
            final String msg = "Error processing TarArchiveInputStream: " + e.getMessage();
            log.error(msg, e);
            throw new UnpackException(msg, e);
        }

        return files;
    }

    @Override
    protected String truncatePackageExtension(String fileName) {
        return fileName.substring(0, fileName.lastIndexOf('.'));
    }

}