(Android™) Convert Java KeyStore to PEM

Loads a Java keystore file and saves the trusted certificate entries to a PEM file.

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);

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

    CkJavaKeyStore jks = new CkJavaKeyStore();

    String jksPassword = "myJksPassword";

    // Load the Java keystore from a file.  The JKS file password is used
    // to verify the keyed digest that is found at the very end of the keystore.
    // It verifies that the keystore has not been modified.
    boolean success = jks.LoadFile(jksPassword,"/someDir/keyStore.jks");
    if (success != true) {
        Log.i(TAG, jks.lastErrorText());
        return;
        }

    // Open/create the output PEM file. 
    // This example uses Chilkat's file access class for writing the output file.
    // You may replace the file I/O lines of code with whatever is most convenient for you.
    CkFileAccess fac = new CkFileAccess();
    success = fac.OpenForWrite("/pemFiles/caCerts.pem");
    if (success != true) {
        Log.i(TAG, fac.lastErrorText());
        return;
        }

    int numCerts = jks.get_NumTrustedCerts();
    int i;

    CkCert cert;
    String pem;

    // Iterate over the trusted certs, get the PEM for each,
    // and append it to the output file.
    i = 0;
    while (i < numCerts) {
        cert = jks.GetTrustedCert(i);

        // Get the certificate in PEM format.  
        pem = cert.exportCertPem();

        // Append the PEM string to the open file.
        // The PEM contains only us-ascii chars..
        success = fac.AppendAnsi(pem);
        if (success != true) {
            Log.i(TAG, fac.lastErrorText());

            return;
            }

        i = i + 1;
        }

    // Close the output file.
    fac.FileClose();

    Log.i(TAG, "Trusted certificates saved to PEM.");

  }

  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."
  }
}