ExtensionElement is now a marker interface that requires all
implementation non-abstract classes to carry a static final QNAME
field (of type QName). This is verified by a new unit test.
Also FullyQualifiedElement is renamed to simply XmlElement. XmlElement
is used over ExtensionElement when implementing classes do not
statically know the qualified name of the XML elements they
represent. In general, XmlElement should be used sparingly, and every
XML element should be modeled by its own Java class (implementing
ExtensionElement).
Smack currently does unnecessary escaping of XML text, where it
escapes e.g. '"' to '"'. This bloats the stanza size, especially
if JSON payloads are involved.
Fixes SMACK-892 (although there are probably still places where
XmlStringBuilder.escape() is used when XmlStringBuild.text() could
have been used).
replaces DefaultExtensionElement which is now deprecated.
Also changes Stanza (and MultiMap) API so that there can be duplicate extension
elements, as this change is required for StandardExtensionElement and by
the XMPP standard.
Florian Schmaus
Paul Schaub