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Java

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

See more Encryption Examples

_LANGUAGE_ 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.

Chilkat Java Downloads

Java
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[])
  {
    boolean success = false;

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

    CkJsonObject jsonCN = new CkJsonObject();
    jsonCN.UpdateString("CN",signingCertSubject);

    CkCert cert = new CkCert();
    success = certStore.FindCert(jsonCN,cert);
    if (success == 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!");
  }
}