Cant retrive Custom Properties from CmisObject (Documentum)

Question

I am trying to retrive all properties from CmisObject but I cant see the custom defined properties which are present in Documentum system.

Document sourceDocument = (Document)getCmisObject(sourceSession, sourceObjectId);

Iterator<Property<?>> propertie =  sourceDocument.getProperties().iterator();
while(propertie.hasNext()){
    System.out.println("Display Name:"+propertie.next().getDisplayName());
    System.out.println("Value:"+propertie.next().getValue().toString());
}

I tried above code . I also tried

Map<String, Object> properties = CMISHelper.objectProperties(sourceDocument);

But coulden't get all custom properties which are present in Documentum system.