Android™ Requires Chilkat v11.7.0+

Password-Protect a PDF with AES-256 Encryption

See more PDF Protection Examples

Demonstrates the simplest way to encrypt a PDF so that it needs a password to open. The passwords come from the UserPassword and OwnerPassword properties, and Protection with the encrypt operation and an empty JSON uses the defaults: AES-256, everything encrypted, every permission granted. Protection only records the security the PDF will be saved with. Nothing is encrypted until WriteFile is called. Android™

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    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 two_page_memo.pdf

    CkPdf pdf = new CkPdf();
    success = pdf.LoadFile("qa_data/pdf/two_page_memo.pdf");
    if (success == false) {
        Log.i(TAG, pdf.lastErrorText());
        return;
        }

    //  The passwords are taken from these two properties at the time Protection is called.
    //  The user password opens the PDF.  The owner password opens it too, and is the one needed
    //  later to change or remove the protection.
    pdf.put_UserPassword("user-secret");
    pdf.put_OwnerPassword("owner-secret");

    //  An empty JSON asks for the defaults: AES-256, everything encrypted, every permission granted.
    CkJsonObject json = new CkJsonObject();
    CkJsonObject jsonOut = new CkJsonObject();
    success = pdf.Protection("encrypt",json,jsonOut);
    if (success == false) {
        Log.i(TAG, pdf.lastErrorText());
        return;
        }

    //  Nothing has been encrypted yet.  "pending" describes the security the PDF will be saved with.
    Log.i(TAG, "algorithm: " + jsonOut.stringOf("pending.algorithm"));
    Log.i(TAG, "PDF version: " + jsonOut.stringOf("pending.pdfVersion"));
    Log.i(TAG, "password needed to open: " + String.valueOf(jsonOut.BoolOf("pending.userPasswordRequired")));

    //  Writing the file applies it.
    success = pdf.WriteFile("qa_output/memo_encrypted.pdf");
    if (success == false) {
        Log.i(TAG, pdf.lastErrorText());
        return;
        }

    //  PreLoadCheck reports a file's encryption without loading it, and needs no password.
    CkPdf checker = new CkPdf();
    CkJsonObject info = new CkJsonObject();
    success = checker.PreLoadCheck("qa_output/memo_encrypted.pdf",info);
    if (success == false) {
        Log.i(TAG, checker.lastErrorText());
        return;
        }

    Log.i(TAG, "encrypted: " + String.valueOf(info.BoolOf("encrypted")));
    Log.i(TAG, "openPasswordRequired: " + String.valueOf(info.BoolOf("openPasswordRequired")));

    //  With the password, the PDF opens normally.
    CkPdf reader = new CkPdf();
    reader.put_UserPassword("user-secret");
    success = reader.LoadFile("qa_output/memo_encrypted.pdf");
    if (success == false) {
        Log.i(TAG, reader.lastErrorText());
        return;
        }

    Log.i(TAG, "pages: " + String.valueOf(reader.get_NumPages()));

    //  Sample output:

    //  algorithm: aes-256
    //  PDF version: 1.7
    //  password needed to open: True
    //  encrypted: True
    //  openPasswordRequired: True
    //  pages: 2

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}