org.codice.ddf.catalog.ui.metacard.impl.ZipSplitter.java Source code

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Here is the source code for org.codice.ddf.catalog.ui.metacard.impl.ZipSplitter.java

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/**
 * Copyright (c) Codice Foundation
 *
 * <p>This is free software: you can redistribute it and/or modify it under the terms of the GNU
 * Lesser General Public License as published by the Free Software Foundation, either version 3 of
 * the License, or any later version.
 *
 * <p>This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details. A copy of the GNU Lesser General Public
 * License is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package org.codice.ddf.catalog.ui.metacard.impl;

import java.io.IOException;
import java.io.InputStream;
import java.io.Serializable;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import javax.activation.MimeType;
import org.apache.commons.io.IOUtils;
import org.codice.ddf.catalog.ui.splitter.StorableResource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/** Splits a ZIP file into its immediate children. Does not recurse through each child item. */
public class ZipSplitter extends AbstractSplitter {

    private static final Logger LOGGER = LoggerFactory.getLogger(ZipSplitter.class);

    public ZipSplitter(String id, Set<MimeType> mimeTypes) {
        super(id, mimeTypes);
    }

    @Override
    public Stream<StorableResource> split(StorableResource storableResource,
            Map<String, ? extends Serializable> arguments) throws IOException {
        ZipIterator zipIterator = new ZipIterator(storableResource.getInputStream());
        return StreamSupport.stream(Spliterators.spliteratorUnknownSize(zipIterator, Spliterator.NONNULL), false)
                .onClose(zipIterator::close);
    }

    @Override
    protected Map<String, Object> getAdditionalProperties() {
        return Collections.emptyMap();
    }

    private static class ZipIterator implements Iterator<StorableResource>, AutoCloseable {

        private ZipInputStream zipInputStream;
        private ZipEntry zipEntry;

        ZipIterator(InputStream inputStream) throws IOException {
            zipInputStream = new ZipInputStream(inputStream);
            zipEntry = zipInputStream.getNextEntry();
        }

        @Override
        public boolean hasNext() {
            return zipEntry != null;
        }

        @Override
        public StorableResource next() {
            if (!hasNext()) {
                throw new NoSuchElementException("There are no more items in the ZIP.");
            }
            try {
                String filename = zipEntry.getName();
                StorableResource storableResource = new StorableResourceImpl(zipInputStream, filename);
                safeCloseEntry();
                zipEntry = zipInputStream.getNextEntry();
                return storableResource;
            } catch (IOException e) {
                String message = "Failed to get the next item in the ZIP file.";
                LOGGER.debug(message, e);
                return new StorableResourceImpl(message);
            }
        }

        @Override
        public void close() {
            if (zipInputStream != null) {
                safeCloseEntry();
                IOUtils.closeQuietly(zipInputStream);
                zipInputStream = null;
                zipEntry = null;
            }
        }

        private void safeCloseEntry() {
            try {
                zipInputStream.closeEntry();
            } catch (IOException e) {
                LOGGER.debug("Unable to close zip entry.", e);
            }
        }
    }
}