(Java) Sign a File to Create a .p7s (Detached Signature)

Java example to create a detached signature file (.p7s) for any type file. The signature can be verified by calling VerifyP7S and passing the original filename and the .p7s filename.

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

    CkCrypt2 crypt = new CkCrypt2();

    // Use a digital certificate and private key from a PFX file (.pfx or .p12).
    String signingCertSubject = "Acme Inc";
    String pfxFilename = "/Users/chilkat/testData/pfx/acme.pfx";
    String pfxPassword = "test123";

    CkCertStore certStore = new CkCertStore();
    boolean success = certStore.LoadPfxFile(pfxFilename,pfxPassword);
    if (success != true) {
        System.out.println(certStore.lastErrorText());
        return;
        }

    CkCert cert = certStore.FindCertBySubjectCN(signingCertSubject);
    if (certStore.get_LastMethodSuccess() == false) {
        System.out.println("Failed to find certificate by subject common name.");
        return;
        }

    // Tell the crypt component to use this cert.
    success = crypt.SetSigningCert(cert);

    // We can sign any type of file, creating a .p7s as output:
    String inFile = "/Users/chilkat/testData/pdf/sample.pdf";
    String sigFile = "/Users/chilkat/testData/p7s/sample.p7s";

    success = crypt.CreateP7S(inFile,sigFile);
    if (success == false) {
        System.out.println(crypt.lastErrorText());

        return;
        }

    success = crypt.VerifyP7S(inFile,sigFile);
    if (success == false) {
        System.out.println(crypt.lastErrorText());

        return;
        }

    System.out.println("Success!");
  }
}