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).
Assume the element
<foo:bar xmlns='namespace' xmlns:foo='foo-namespace'/>
then the <bar/> element's namespace is 'foo-namespace', but the
default namespace is 'namespace'. And this is the namespace that
scopes into inner elements.
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).
This means that users get now exceptions with helpful error messages
instead of the dreaded ClassCastException, like
java.lang.ClassCastException: org.jivesoftware.smack.packet.StandardExtensionElement cannot be cast to org.jivesoftware.smackx.mam.element.MamElements$MamResultExtension
at
when StanzaView.getExtension(Class) is used to retrieve the extension.
When sending a stream-open-like element, it depends on the actual used
transport which element is send. For example, RFC6120-style TCP uses
<stream>, whereas the Websocket binding for XMPP uses <open/>.
Most of the times when we construct a stream-open-like element, we
want the jabber:client namespace. Hence add a constructor that does
select the namespace implicitly.
Before the existence of AbstractStreamOpen, StreamOpen sufficed our need
during sending an open stream element. Since the intention behind
introducing AbstractStreamOpen is to allow underlying transports provide
transport specific opening streams, these changes will further support
the cause.
This commit will allow us to send transport specific open element
which should be inherited from AbstractStreamOpen.
This method was removed with 07da9ffb4 ("Do not have
Stanza.getExtension(String, String) return a generic type"). In order
to aide migration to the newer API, this commit re-adds the method and
marks it as deprecated.
Ensure that he returned extension element is actually of the correct
type. It should not be common, but in theory, Smack's provider
architecture would allow for different types to be returned than the
ones one may expect.
Returning a generic would allow for
List<ExtensionElement> list = stanza.getExtension("foo", "bar");
to compile (Note the we are calling getExtension(), not
getExtension*s*()).
Users are encouraged to use the type safe getExtension(Class<? extends
ExtensionElement) variant instead.
Fixes SMACK-825.