(Android™) Change Password for Java KeyStore File

Demonstrates how to load a Java keystore, change the password, and save using the new password. If the Java keystore contains only trusted root certificates, then it's simply a matter of loading the JKS with the existing password, and then saving with a new password. If the JKS contains private key entries, then each private key entry must be re-keyed using the new password by calling the ChangePassword method.

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 oldJksPassword = "existingPassword";
    String newJksPassword = "newPassword";
    String jksPath = "/someDir/keyStore.jks";

    // Load the Java keystore from a file.
    boolean success = jks.LoadFile(oldJksPassword,jksPath);
    if (success != true) {
        Log.i(TAG, jks.lastErrorText());
        return;
        }

    // If the JKS contains private key entries, then each
    // must be re-keyed with the new password by calling ChangePassword.
    int numPrivateKeys = jks.get_NumPrivateKeys();

    int i = 0;
    while (i < numPrivateKeys) {

        success = jks.ChangePassword(i,oldJksPassword,newJksPassword);
        if (success != true) {
            Log.i(TAG, jks.lastErrorText());
            return;
            }

        i = i + 1;
        }

    // Write the JKS using the new password for the JKS file's keyed digest.
    success = jks.ToFile(newJksPassword,jksPath);
    if (success != true) {
        Log.i(TAG, jks.lastErrorText());
        return;
        }

    Log.i(TAG, "Updated the password for the Java keystore file.");

  }

  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."
  }
}