org.ala.harvester.ExtractPubfSciNamesAndImages.java Source code

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Here is the source code for org.ala.harvester.ExtractPubfSciNamesAndImages.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 org.ala.harvester;

import org.apache.commons.io.FileUtils;
import org.apache.pdfbox.exceptions.InvalidPasswordException;

import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDXObjectImage;
import org.apache.pdfbox.util.PDFTextStripperByArea;

import java.awt.Rectangle;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;

import java.util.Iterator;
import java.util.List;
import java.util.Map;

/**
 * This is an example on how to extract text from a specific area on the PDF document.
 *
 * Usage: java org.apache.pdfbox.examples.util.ExtractTextByArea <input-pdf>
 *
 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
 * @version $Revision: 1.2 $
 */
public class ExtractPubfSciNamesAndImages {

    private static int imageCounter = 1;

    private ExtractPubfSciNamesAndImages() {
        //utility class and should not be constructed.
    }

    /**
     * This will print the documents text in a certain area.
     *
     * @param args The command line arguments.
     *
     * @throws Exception If there is an error parsing the document.
     */
    public static void main(String[] args) throws Exception {
        if (args.length != 1) {
            usage();
        } else {
            PDDocument document = null;
            try {
                document = PDDocument.load(args[0]);
                if (document.isEncrypted()) {
                    try {
                        document.decrypt("");
                    } catch (InvalidPasswordException e) {
                        System.err.println("Error: Document is encrypted with a password.");
                        System.exit(1);
                    }
                }

                extractSciNameAndImages(document);

            } finally {
                if (document != null) {
                    document.close();
                }
            }
        }
    }

    private static void extractSciNameAndImages(PDDocument document) throws IOException {
        PDFTextStripperByArea stripper = new PDFTextStripperByArea();
        stripper.setSortByPosition(true);
        Rectangle rect = new Rectangle(10, 60, 275, 20);
        stripper.addRegion("class1", rect);
        List allPages = document.getDocumentCatalog().getAllPages();

        Writer writer = getSiteMapWriter("anic");

        writeColumnHeaders(writer);

        for (int pageNum = 37; pageNum <= 249; pageNum++) {
            //        for (int pageNum = 156; pageNum <= 156; pageNum++) {
            PDPage page = (PDPage) allPages.get(pageNum);
            PDResources resources = page.getResources();
            Map images = resources.getImages();
            stripper.extractRegions(page);

            String sciName = stripper.getTextForRegion("class1").trim();
            System.out.println("Scientific Name: " + sciName);

            if (images != null) {
                Iterator imageIter = images.keySet().iterator();
                while (imageIter.hasNext()) {
                    String key = (String) imageIter.next();
                    PDXObjectImage image = (PDXObjectImage) images.get(key);
                    String name = null;

                    if ("jpg".equals(image.getSuffix())) {
                        name = getUniqueFileName(sciName + "_" + key, image.getSuffix());
                        System.out.println("Writing image:" + name);
                        image.write2file("/data/tmp/" + name);

                        writer.write(sciName);
                        writer.write(",");
                        writer.write(name + "." + image.getSuffix());
                        writer.write("\n");
                    }
                }
            }
        }
    }

    private static void writeColumnHeaders(Writer writer) throws IOException {
        writer.write("SPECIES");
        writer.write(",");
        writer.write("FILE_NAME");
        writer.write("\n");
    }

    private static Writer getSiteMapWriter(String infosourceSimpleName) throws IOException {
        String dataDir = "/data/mapping/";
        FileUtils.forceMkdir(new File(dataDir));
        File siteMapFile = new File(dataDir + "perth_urban_bushland_fungi.csv");
        if (siteMapFile.exists())
            FileUtils.forceDelete(siteMapFile);
        return new FileWriter(siteMapFile);
    }

    private static String getUniqueFileName(String prefix, String suffix) {
        String uniqueName = null;
        File f = null;
        while (f == null || f.exists()) {
            uniqueName = prefix + "-" + imageCounter;
            f = new File(uniqueName + "." + suffix);
            imageCounter++;
        }
        return uniqueName;
    }

    /**
     * This will print the usage for this document.
     */
    private static void usage() {
        System.err.println("Usage: java org.apache.pdfbox.examples.util.ExtractTextByArea <input-pdf>");
    }

}