extractor.pdftotext.PdfToText.java Source code

Introduction

Here is the source code for extractor.pdftotext.PdfToText.java

Source

/*
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 */
package extractor.pdftotext;

import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.text.PDFTextStripper;

import com.snowtide.PDF;
import com.snowtide.pdf.Document;
import com.snowtide.pdf.OutputTarget;

/**
 *
 * @author kodi
 */
public class PdfToText {

    public String getText(File file) throws IOException {
        String rawText = getPdfBoxRaw(file);
        String cleanText = getCleanText(rawText);
        if (cleanText.length() < 5) {
            rawText = getPdfXStreamRaw(file);
            cleanText = getCleanText(rawText);
        }
        return cleanText;

    }

    private String getPdfBoxRaw(File file) {
        try {
            PDDocument doc = PDDocument.load(file);
            PDFTextStripper stripper = new PDFTextStripper();

            stripper.setPageStart("PAGE START");
            stripper.setPageEnd("PAGE END");
            //gets the text form the doc and replaces unknown signs with \n
            String rawText = stripper.getText(doc).replaceAll("[\\p{Cc}\\p{Cf}\\p{Co}\\p{Cn}]", "\n");
            doc.close();
            return rawText;

        } catch (IOException ex) {
            Logger.getLogger(PdfToText.class.getName()).log(Level.SEVERE, null, ex);
        }
        return "";
    }

    private String getPdfXStreamRaw(File file) {
        try {
            Document doc = PDF.open(file);
            StringBuilder text = new StringBuilder(1024);
            doc.pipe(new OutputTarget(text));
            doc.close();
            return text.toString();
        } catch (IOException ex) {
            Logger.getLogger(PdfToText.class.getName()).log(Level.SEVERE, null, ex);
        }
        return "";
    }

    private String getCleanText(String rawText) {
        String cleanFundingText = "";
        Pattern p = Pattern.compile(
                "[\\.\\n\\r]?((?:Funding(s)?(/Support)?(\\ssources)?|Acknowledg(e)?ment(s)?(:)?|[cC]onflict.+\\s[iI]nterests|ACKNOWLEDG(E)?MENTS(S)?)(?:[\\r\\n]+.*?)+\\.)(?:[\\r\\n]*[A-Za-z]*(\\s[A-Za-z]*)?[\\r\\n]+)");
        Matcher m = p.matcher(rawText);
        while (m.find()) {
            String fundingText = m.group(1);
            //System.out.print(fundingText+"\n");
            String[] lines = fundingText.split("[\\r\\n]");
            for (String line : lines) {
                //remove the header lines
                if (!line.contains("PAGE START") && !line.contains("PAGE END")) {
                    if (line.endsWith(" ") || line.endsWith("-")) {
                        cleanFundingText = cleanFundingText + line;
                    } else {
                        cleanFundingText = cleanFundingText + line + ' ';
                    }
                }
            }
        }
        System.out.print(cleanFundingText + "\n");
        return cleanFundingText;
    }
}