Java Tutorial/PDF/Metadata

Add XMP metadata automatically, based on the PDF metadata

import java.io.FileOutputStream;
import com.lowagie.text.Document;
import com.lowagie.text.Paragraph;
import com.lowagie.text.pdf.PdfWriter;
public class MainClass {
  public static void main(String[] args) throws Exception {
    Document document = new Document();
    PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream("2.pdf"));
    document.addTitle("title");
    document.addSubject("subject");
    document.addKeywords("keywords");
    document.addCreator("creator");
    document.addAuthor("author");
    writer.createXmpMetadata();
    document.open();
    document.add(new Paragraph("Hello World"));
    document.close();
  }
}

Get meta data from pdf document

import java.util.Iterator;
import java.util.Map;
import com.lowagie.text.pdf.PdfReader;
public class MainClass {
  public static void main(String[] args) throws Exception {
    PdfReader reader = new PdfReader("2.pdf");
    Map info = reader.getInfo();
    for (Iterator i = info.keySet().iterator(); i.hasNext();) {
      String key = (String) i.next();
      String value = (String) info.get(key);
      System.out.println(key + ": " + value);
    }
    if (reader.getMetadata() == null) {
      System.out.println("No XML Metadata.");
    } else {
      System.out.println("XML Metadata: " + new String(reader.getMetadata()));
    }
  }
}

Get Pdf metadata

import java.util.Iterator;
import java.util.Map;
import com.lowagie.text.pdf.PdfReader;
public class MainClass {
  public static void main(String[] args) throws Exception {
    PdfReader reader = new PdfReader("HelloWorldToRead.pdf");
    if (reader.getMetadata() == null) {
      System.out.println("No XML Metadata.");
    } else {
      System.out.println("XML Metadata: " + new String(reader.getMetadata()));
    }
  }
}

Read PDF to add some metadata

import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.util.HashMap;
import com.lowagie.text.Document;
import com.lowagie.text.Paragraph;
import com.lowagie.text.pdf.PdfReader;
import com.lowagie.text.pdf.PdfStamper;
import com.lowagie.text.pdf.PdfWriter;
import com.lowagie.text.xml.xmp.XmpWriter;
public class HelloWorldAddMetadata {
  public static void main(String[] args) throws Exception {
    Document document = new Document();
    PdfWriter.getInstance(document, new FileOutputStream("HelloWorld.pdf"));
    document.open();
    document.add(new Paragraph("Hello World"));
    document.close();
    PdfReader reader = new PdfReader("HelloWorld.pdf");
    System.out.println("Tampered? " + reader.isTampered());
    PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(
        "HelloWorldStampedMetadata.pdf"));
    System.out.println("Tampered? " + reader.isTampered());
    HashMap<String, String> info = reader.getInfo();
    info.put("Subject", "Hello World");
    info.put("Author", "your name");
    info.put("Keywords", "iText pdf");
    info.put("Title", "Hello World stamped");
    info.put("Creator", "your name");
    stamper.setMoreInfo(info);
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    XmpWriter xmp = new XmpWriter(baos, info);
    xmp.close();
    stamper.setXmpMetadata(baos.toByteArray());
    stamper.close();
  }
}

Set meta data to pdf document

import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.util.HashMap;
import com.lowagie.text.Document;
import com.lowagie.text.Paragraph;
import com.lowagie.text.pdf.PdfReader;
import com.lowagie.text.pdf.PdfStamper;
import com.lowagie.text.pdf.PdfWriter;
import com.lowagie.text.xml.xmp.XmpWriter;
public class MainClass {
  public static void main(String[] args) throws Exception {
    Document document = new Document();
    PdfWriter.getInstance(document, new FileOutputStream("2.pdf"));
    document.open();
    document.add(new Paragraph("Hello World"));
    document.close();
    PdfReader reader = new PdfReader("2.pdf");
    System.out.println("Tampered? " + reader.isTampered());
    PdfStamper stamper = new PdfStamper(reader, new FileOutputStream("2.pdf"));
    HashMap info = reader.getInfo();
    info.put("Subject", "subject");
    info.put("Author", "author");
    info.put("Keywords", "keywords");
    info.put("Title", "title");
    info.put("Creator", "creator");
    stamper.setMoreInfo(info);
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    XmpWriter xmp = new XmpWriter(baos, info);
    xmp.close();
    stamper.setXmpMetadata(baos.toByteArray());
    stamper.close();
  }
}

use PdfSchema to update Meta data

import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import com.lowagie.text.Document;
import com.lowagie.text.Paragraph;
import com.lowagie.text.pdf.PdfWriter;
import com.lowagie.text.xml.xmp.DublinCoreSchema;
import com.lowagie.text.xml.xmp.PdfSchema;
import com.lowagie.text.xml.xmp.XmpArray;
import com.lowagie.text.xml.xmp.XmpSchema;
import com.lowagie.text.xml.xmp.XmpWriter;
public class MainClass {
  public static void main(String[] args) throws Exception {
    Document document = new Document();
    PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream("2.pdf"));
    ByteArrayOutputStream os = new ByteArrayOutputStream();
    XmpWriter xmp = new XmpWriter(os);
    XmpSchema dc = new DublinCoreSchema();
    XmpArray subject = new XmpArray(XmpArray.UNORDERED);
    subject.add("Metadata");
    dc.setProperty(DublinCoreSchema.SUBJECT, subject);
    xmp.addRdfDescription(dc);
    PdfSchema pdf = new PdfSchema();
    pdf.setProperty(PdfSchema.KEYWORDS, "Hello World, XMP, Metadata");
    pdf.setProperty(PdfSchema.VERSION, "1.4");
    xmp.addRdfDescription(pdf);
    xmp.close();
    writer.setXmpMetadata(os.toByteArray());
    document.open();
    document.add(new Paragraph("Hello World"));
    document.close();
  }
}