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Java Requires Chilkat v11.7.0+

Tile a Watermark Across a PDF Page

See more PDF Watermark Examples

Demonstrates a tiled watermark, which repeats the stamp over the whole page instead of placing it once. Tiling overrides position.align; tile.spacingX and spacingY set the gaps, and tile.stagger offsets alternate rows by half a tile so the pattern does not line up in columns. A faint tiled stamp carrying the name or address is the usual way to mark a document so that a leaked copy can be traced back, and zOrder back keeps it behind the text where it does not hinder reading.

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Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  This example requires the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    //  The PDF used in this example is available at long_report.pdf

    CkPdf pdf = new CkPdf();
    success = pdf.LoadFile("qa_data/pdf/long_report.pdf");
    if (success == false) {
        System.out.println(pdf.lastErrorText());
        return;
        }

    CkJsonObject json = new CkJsonObject();
    json.UpdateString("type","text");

    //  {date:FORMAT} is replaced per page when the watermark is added.  The other placeholders are
    //  {page}, {pages} and {filename}; {{ gives a literal brace.
    json.UpdateString("text","jdoe@example.com  {date:yyyy-MM-dd}");
    json.UpdateString("id","trace");
    json.UpdateString("zOrder","back");
    json.UpdateNumber("font.size","14");
    json.UpdateNumber("opacity","0.15");
    json.UpdateNumber("rotation","30");

    json.UpdateBool("tile.enabled",true);
    json.UpdateNumber("tile.spacingX","60");
    json.UpdateNumber("tile.spacingY","80");
    json.UpdateBool("tile.stagger",true);

    CkJsonObject jsonOut = new CkJsonObject();
    success = pdf.Watermark("add",json,jsonOut);
    if (success == false) {
        System.out.println(pdf.lastErrorText());
        return;
        }

    System.out.println("id: " + jsonOut.stringOf("id") + " pages: " + jsonOut.stringOf("pages"));

    success = pdf.WriteFile("qa_output/report_traced.pdf");
    if (success == false) {
        System.out.println(pdf.lastErrorText());
        return;
        }

    //  Sample output:

    //  id: trace pages: 1-3
  }
}