mj.ocraptor.extraction.tika.parser.epub.EpubParser.java Source code

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Here is the source code for mj.ocraptor.extraction.tika.parser.epub.EpubParser.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 mj.ocraptor.extraction.tika.parser.epub;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

import mj.ocraptor.configuration.Config;
import mj.ocraptor.configuration.properties.ConfigBool;
import mj.ocraptor.extraction.image_processing.TikaImageHelper;
import mj.ocraptor.extraction.tika.parser.xml.DcXMLParser;
import mj.ocraptor.file_handler.filter.FileType;

import org.apache.commons.io.FilenameUtils;
import org.apache.tika.exception.TikaException;
import org.apache.tika.io.IOUtils;
import org.apache.tika.metadata.Metadata;
import org.apache.tika.mime.MediaType;
import org.apache.tika.parser.AbstractParser;
import org.apache.tika.parser.ParseContext;
import org.apache.tika.parser.Parser;
import org.apache.tika.sax.BodyContentHandler;
import org.apache.tika.sax.EmbeddedContentHandler;
import org.apache.tika.sax.XHTMLContentHandler;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * Epub parser
 */
public class EpubParser extends AbstractParser {

    /** Serial version UID */
    private static final long serialVersionUID = 215176772484050550L;

    private static final Set<MediaType> SUPPORTED_TYPES = Collections.unmodifiableSet(new HashSet<MediaType>(
            Arrays.asList(MediaType.application("epub+zip"), MediaType.application("x-ibooks+zip"))));

    private Parser meta = new DcXMLParser();

    private Parser content = new EpubContentParser();

    public Parser getMetaParser() {
        return meta;
    }

    public void setMetaParser(Parser meta) {
        this.meta = meta;
    }

    public Parser getContentParser() {
        return content;
    }

    public void setContentParser(Parser content) {
        this.content = content;
    }

    public Set<MediaType> getSupportedTypes(ParseContext context) {
        return SUPPORTED_TYPES;
    }

    public void parse(InputStream stream, ContentHandler handler, Metadata metadata, ParseContext context)
            throws IOException, SAXException, TikaException {
        // Because an EPub file is often made up of multiple XHTML files,
        // we need explicit control over the start and end of the document
        XHTMLContentHandler xhtml = new XHTMLContentHandler(handler, metadata);
        xhtml.startDocument();
        ContentHandler childHandler = new EmbeddedContentHandler(new BodyContentHandler(xhtml));

        ZipInputStream zip = new ZipInputStream(stream);
        ZipEntry entry = zip.getNextEntry();

        TikaImageHelper helper = new TikaImageHelper(metadata);
        try {
            while (entry != null) {
                // TODO: images
                String entryExtension = null;
                try {
                    entryExtension = FilenameUtils.getExtension(new File(entry.getName()).getName());
                } catch (Exception e) {
                    e.printStackTrace();
                }
                if (entryExtension != null && FileType.isValidImageFileExtension(entryExtension)
                        && Config.inst().getProp(ConfigBool.ENABLE_IMAGE_OCR)) {
                    File imageFile = null;
                    try {
                        imageFile = TikaImageHelper.saveZipEntryToTemp(zip, entry);
                        helper.addImage(imageFile);
                    } catch (Exception e) {
                        e.printStackTrace();
                    } finally {
                        if (imageFile != null) {
                            imageFile.delete();
                        }
                    }
                } else if (entry.getName().equals("mimetype")) {
                    String type = IOUtils.toString(zip, "UTF-8");
                    metadata.set(Metadata.CONTENT_TYPE, type);
                } else if (entry.getName().equals("metadata.xml")) {
                    meta.parse(zip, new DefaultHandler(), metadata, context);
                } else if (entry.getName().endsWith(".opf")) {
                    meta.parse(zip, new DefaultHandler(), metadata, context);
                } else if (entry.getName().endsWith(".html") || entry.getName().endsWith(".xhtml")) {
                    content.parse(zip, childHandler, metadata, context);
                }
                entry = zip.getNextEntry();
            }
            helper.addTextToHandler(xhtml);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (helper != null) {
                helper.close();
            }
        }

        // Finish everything
        xhtml.endDocument();
    }

}