(Android™) S/MIME Encrypt .eml without Sending

See more Email Object Examples

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// 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.

    CkEmail email = new CkEmail();

    success = email.LoadEml("c:/temp/email/unencrypted.eml");
    if (success == false) {
        Log.i(TAG, email.lastErrorText());
        return;
        }

    // The email content is encrypted using AES with a 256-bit key, operating in GCM mode, which provides authenticated encryption.
    email.put_Pkcs7CryptAlg("aes-gcm");
    email.put_Pkcs7KeyLength(256);
    email.put_OaepPadding(true);
    email.put_OaepHash("sha256");
    email.put_OaepMgfHash("sha256");

    CkCert cert = new CkCert();
    success = cert.LoadFromFile("c/temps/cert/recipient.cer");
    if (success == false) {
        Log.i(TAG, cert.lastErrorText());
        return;
        }

    email.put_SendEncrypted(true);
    email.SetEncryptCert(cert);

    CkStringBuilder sbSmime = new CkStringBuilder();

    // The mailman object applies the encryption by rendering the email according to the instructions (property settings) provided in the email object.
    // No email is sent.
    CkMailMan mailman = new CkMailMan();
    success = mailman.RenderToMimeSb(email,sbSmime);
    if (success == false) {
        Log.i(TAG, mailman.lastErrorText());
        return;
        }

    success = sbSmime.WriteFile("c:/temp/encryptedEmail.eml","utf-8",false);
    if (success == false) {
        Log.i(TAG, mailman.lastErrorText());
        return;
        }

    Log.i(TAG, "Success!");

  }

  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."
  }
}