Android™
Calculate HRMC IRMark

See more XML Digital Signatures Examples
Demonstrates how to calculate an IRmark for an HMRC GovTalkMessage XML document.
Chilkat Android™ Downloads

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

    // First build a sample (but incomplete) GovTalkMessage.
    // You can replace this code with a call to LoadXml or LoadXmlFile..
    // 
    // Note: The online tool at https://tools.chilkat.io/xmlCreate.cshtml
    // can be used to generate XML code that creates a given XML document.
    CkXml xml = new CkXml();
    xml.put_Tag("GovTalkMessage");
    xml.AddAttribute("xmlns","http://www.govtalk.gov.uk/CM/envelope");
    xml.UpdateAttrAt("Body|Message",true,"xmlns","urn:g3.ge:dea:call:SendDocument:v1");
    xml.UpdateChildContent("Body|Message","................");

    // This is the XML created:
    // <?xml version="1.0" encoding="utf-8" ?>
    // <GovTalkMessage xmlns="http://www.govtalk.gov.uk/CM/envelope">
    //     <Body>
    //         <Message xmlns="urn:g3.ge:dea:call:SendDocument:v1">................</Message>
    //     </Body>
    // </GovTalkMessage>

    Log.i(TAG, xml.getXml());

    // Canonicalize the XML (using C14N)
    CkXmlDSig xdsig = new CkXmlDSig();
    boolean withComments = false;
    String canonXml = xdsig.canonicalizeXml(xml.getXml(),"C14N",withComments);

    // Return the base64 SHA-1 HASH of the canonical XML.
    CkCrypt2 crypt = new CkCrypt2();
    crypt.put_HashAlgorithm("sha1");
    crypt.put_EncodingMode("base64");
    String irmark = crypt.hashStringENC(canonXml);

    Log.i(TAG, "IRMark = " + irmark);

  }

  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."
  }
}