DefiningQualifyingProperties

Data Object Properties

The classes that represent the signed data objects also enable the specification of the qualifying properties that apply to each data object, such as DataObjectFormat and IndividualDataObjectTimeStamp.

DataObjectDesc obj = new DataObjectReference("rfc3161.txt")
   .withDataObjectFormat(new DataObjectFormatProperty("text/plain"))
   .withDataObjectTimeStamp();

Some qualifying properties apply to all the data objects that are present on a signature. Those properties can be defined using the SignedDataObjects class.

SignedDataObjects dataObjs = new SignedDataObjects(obj)    
   .withCommitmentType(AllDataObjsCommitmentTypeProperty.proofOfOrigin())
   .withDataObjectsTimeStamp();

Another option to define data object properties is to use a custom DataObjectPropertiesProvider which is invoked when no properties are explicitly specified for a given object. This can be useful when all the data objects share the same properties.

Optional Signature Properties

Most XAdES qualifying properties are part of the different signature forms. As such, XAdES4j always includes the properties for the form in use when creating a signature. For instance, if a XadesTSigningProfile is used, the resulting signer will always include the SignatureTimeStamp property.

Nevertheless, XAdES includes some optional signature properties, such as SignatureProductionPlace and CounterSignature, that can be used with all the forms. These properties can be included using a custom SignaturePropertiesProvider which is configured in the signing profile, as all the other providers.

XadesSigningProfile profile = new XadesBesSigningProfile(...).withSignaturePropertiesProvider(new SignaturePropertiesProvider()
{
   @Override
   public void provideProperties(SignaturePropertiesCollector signedPropsCol)
   {
      signedPropsCol.setSignerRole(new SignerRoleProperty("CTO"));
      signedPropsCol.setSignatureProductionPlace(new SignatureProductionPlaceProperty("City", "Country"));
      signaturePropsCol.setSigningTime(new SigningTimeProperty());
   }
});

The default SignaturePropertiesProvider only includes the SigningTime property.

SigningTime

Formats such as yyyy-MM-dd'T'HH:mm:ss'Z' or yyyy-MM-dd'T'HH:mm:ss.fff'Z' can be achieved by crafting the Calendar instance provided to the SigningTimeProperty, since time-zone information is preserved by JAXB's built-in date conversion. The following code results in "2020-05-01T22:30:00Z":

Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
c.clear();
c.set(2020, 4, 1, 22, 30);
signedPropsCol.setSigningTime(new SigningTimeProperty(c));