Skip navigation

Category Archives: Java

This is a simple java app that uses the PDFBox library to locate text within a PDF document. This app is designed to be run from the command line, originally by a python script. Given a PDF it will parse the entire document and produce a comma delimited string of the identified word followed by the page number in parenthesis and the x/y coordinates within brackets of the top left corner of the first letter. Words are identified by character groupings and simple spaces and punctuation placement. For the most part all of the magic here is performed by PDFBox which is a fantastic library for parsing PDFs. This is a rough and rather featureless version of the one I used in production and could certainly use some improvement though it’s a good place to start if you can’t find a working example.

Output will be similar to:
[(1)[190.3 : 286.8] WORD1, (1)[283.3 : 286.8] WORD2, ...]

Dependencies:

package printtextlocations;

import java.io.File;
import java.io.IOException;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.apache.pdfbox.exceptions.InvalidPasswordException;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.common.PDStream;
import org.apache.pdfbox.util.PDFTextStripper;
import org.apache.pdfbox.util.TextPosition;

public class PrintTextLocations extends PDFTextStripper {

    public static StringBuilder tWord = new StringBuilder();
    public static String seek;
    public static String[] seekA;
    public static List wordList = new ArrayList();
    public static boolean is1stChar = true;
    public static boolean lineMatch;
    public static int pageNo = 1;
    public static double lastYVal;

    public PrintTextLocations()
            throws IOException {
        super.setSortByPosition(true);
    }

    public static void main(String[] args)
            throws Exception {
        PDDocument document = null;
        seekA = args[1].split(",");
        seek = args[1];
        try {
            File input = new File(args[0]);
            document = PDDocument.load(input);
            if (document.isEncrypted()) {
                try {
                    document.decrypt("");
                } catch (InvalidPasswordException e) {
                    System.err.println("Error: Document is encrypted with a password.");
                    System.exit(1);
                }
            }
            PrintTextLocations printer = new PrintTextLocations();
            List allPages = document.getDocumentCatalog().getAllPages();

            for (int i = 0; i < allPages.size(); i++) {
                PDPage page = (PDPage) allPages.get(i);
                PDStream contents = page.getContents();

                if (contents != null) {
                    printer.processStream(page, page.findResources(), page.getContents().getStream());
                }
                pageNo += 1;
            }
        } finally {
            if (document != null) {
                System.out.println(wordList);
                document.close();
            }
        }
    }

    @Override
    protected void processTextPosition(TextPosition text) {
        String tChar = text.getCharacter();
        System.out.println("String[" + text.getXDirAdj() + ","
                + text.getYDirAdj() + " fs=" + text.getFontSize() + " xscale="
                + text.getXScale() + " height=" + text.getHeightDir() + " space="
                + text.getWidthOfSpace() + " width="
                + text.getWidthDirAdj() + "]" + text.getCharacter());
        String REGEX = "[,.\\[\\](:;!?)/]";
        char c = tChar.charAt(0);
        lineMatch = matchCharLine(text);
        if ((!tChar.matches(REGEX)) && (!Character.isWhitespace(c))) {
            if ((!is1stChar) && (lineMatch == true)) {
                appendChar(tChar);
            } else if (is1stChar == true) {
                setWordCoord(text, tChar);
            }
        } else {
            endWord();
        }
    }

    protected void appendChar(String tChar) {
        tWord.append(tChar);
        is1stChar = false;
    }

    protected void setWordCoord(TextPosition text, String tChar) {
        tWord.append("(").append(pageNo).append(")[").append(roundVal(Float.valueOf(text.getXDirAdj()))).append(" : ").append(roundVal(Float.valueOf(text.getYDirAdj()))).append("] ").append(tChar);
        is1stChar = false;
    }

    protected void endWord() {
        String newWord = tWord.toString().replaceAll("[^\\x00-\\x7F]", "");
        String sWord = newWord.substring(newWord.lastIndexOf(' ') + 1);
        if (!"".equals(sWord)) {
            if (Arrays.asList(seekA).contains(sWord)) {
                wordList.add(newWord);
            } else if ("SHOWMETHEMONEY".equals(seek)) {
                wordList.add(newWord);
            }
        }
        tWord.delete(0, tWord.length());
        is1stChar = true;
    }

    protected boolean matchCharLine(TextPosition text) {
        Double yVal = roundVal(Float.valueOf(text.getYDirAdj()));
        if (yVal.doubleValue() == lastYVal) {
            return true;
        }
        lastYVal = yVal.doubleValue();
        endWord();
        return false;
    }

    protected Double roundVal(Float yVal) {
        DecimalFormat rounded = new DecimalFormat("0.0'0'");
        Double yValDub = new Double(rounded.format(yVal));
        return yValDub;
    }
}