Signing XML File Content with p12 File

xml_signing.java

  public static String signXmlContent(String inputFile, String keyStoreFilePath,
      String keyStorePassword, String keyStoreAlias) throws Exception {

    KeyStore keyStore = KeyStore.getInstance("PKCS12");
    keyStore.load(new FileInputStream(keyStoreFilePath), keyStorePassword.toCharArray());
    DocumentBuilderFactory buildFactory = DocumentBuilderFactory.newInstance();
    buildFactory.setNamespaceAware(true);
    Document document = buildFactory.newDocumentBuilder().parse(inputFile);
    XMLSignatureFactory xmLSignatureFactory = XMLSignatureFactory.getInstance("DOM",
        (Provider) Class.forName("org.jcp.xml.dsig.internal.dom.XMLDSigRI").newInstance());
    KeyInfoFactory keyInfoFactory = xmLSignatureFactory.getKeyInfoFactory();
    XMLSignature signature = xmLSignatureFactory.newXMLSignature(xmLSignatureFactory.newSignedInfo(
        xmLSignatureFactory.newCanonicalizationMethod(CanonicalizationMethod.INCLUSIVE,
            (C14NMethodParameterSpec) null),
        xmLSignatureFactory.newSignatureMethod("http://www.w3.org/2001/04/xmldsig-more#rsa-sha256",
            null), Collections.singletonList(xmLSignatureFactory.newReference("",
            xmLSignatureFactory.newDigestMethod(DigestMethod.SHA256, null),
            Collections.singletonList(xmLSignatureFactory.newTransform(Transform.ENVELOPED,
                (TransformParameterSpec) null)), null, null))), keyInfoFactory.newKeyInfo(
        new ArrayList<>(Collections.singletonList(keyInfoFactory.newX509Data(
            new ArrayList<>(Collections.singletonList(keyStore.getCertificate(keyStoreAlias))))))));
    signature.sign(
        new DOMSignContext(keyStore.getKey(keyStoreAlias, keyStorePassword.toCharArray()),
            document.getDocumentElement()));
    StringWriter stringWriter = new StringWriter();
    TransformerFactory.newInstance().newTransformer()
        .transform(new DOMSource(document.getDocumentElement()), new StreamResult(stringWriter));
    String result = stringWriter.toString().replaceAll("&#13;", "");

    return result;
  }