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

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Here is the source code for org.dataconservancy.ui.util.ZipPackageExtractor.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.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import java.util.zip.ZipInputStream;

import net.sourceforge.stripes.action.FileBean;

import org.apache.commons.io.IOUtils;

import org.dataconservancy.ui.exceptions.UnpackException;

/**
 * An implementation of {@link PackageExtractor} handling specifically .zip files.
 */
public class ZipPackageExtractor extends BasePackageExtractor {

    @Override
    protected List<File> unpackFilesFromArchive(File file, String packageDir) throws Exception {
        if (file != null) {
            return unpackFilesFromStream(new ZipInputStream(new FileInputStream(file)), packageDir, file.getName());
        }

        return Collections.emptyList();
    }

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

        if (!ZipInputStream.class.isAssignableFrom(packageInputStream.getClass())) {
            zipInStream = new ZipInputStream(packageInputStream);
        } else {
            zipInStream = (ZipInputStream) packageInputStream;
        }

        List<File> files = new ArrayList<File>();
        try {
            ZipEntry entry = zipInStream.getNextEntry();
            //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, zipInStream);
                        files.addAll(savedFiles);
                    }
                }
                entry = zipInStream.getNextEntry();
            }

            zipInStream.close();
        } catch (IOException e) {
            final String msg = "Error processing ZipInputStream: " + 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('.'));
    }

}