(Java) Convert Java KeyStore to PEM

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

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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[])
  {
    // 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) {
        System.out.println(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) {
        System.out.println(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) {
            System.out.println(fac.lastErrorText());

            return;
            }

        i = i+1;
        }

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

    System.out.println("Trusted certificates saved to PEM.");
  }
}