rocks.xmpp.core.stanza.model

Class Stanza

java.lang.Object

rocks.xmpp.core.stanza.model.Stanza

All Implemented Interfaces:

StreamElement

Direct Known Subclasses:

IQ, Message, Presence

public abstract class Stanza
extends Object
implements StreamElement

The abstract base class for a XML stanza.

8. XML Stanzas

After a client and a server (or two servers) have completed stream negotiation, either party can send XML stanzas. Three kinds of XML stanza are defined for the 'jabber:client' and 'jabber:server' namespaces: <message/>, <presence/>, and <iq/>.

Method Summary

Modifier and Type	Method and Description
abstract Stanza	createError(Condition condition) Creates an error response for this stanza.
abstract Stanza	createError(StanzaError error) Creates an error response for this stanza.
StanzaError	getError() Gets the stanza's 'error' element.
<T> T	getExtension(Class<T> clazz) Gets the extension of the given type or null, if there's no such extension.
Jid	getFrom() Gets the stanza's 'from' attribute.
String	getId() Gets the stanza's 'id' attribute.
String	getLanguage() Gets the stanza's 'xml:lang' attribute, i.e. its language.
Jid	getTo() Gets the stanza's 'to' attribute, i.e. the recipient.
boolean	hasExtension(Class<?> clazz) Checks if the stanza has an extension of the given type.
void	setError(StanzaError stanzaError) Sets the stanza's 'error' element.
void	setFrom(Jid from) Sets the stanza's 'from' attribute, i.e. the sender.
void	setId(String id) Sets the stanza's 'id' attribute.
void	setLanguage(String language) Sets the stanza's 'xml:lang' attribute, i.e. its language.
void	setTo(Jid to) Sets the stanza's 'to' attribute, i.e. the recipient.
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

getFrom

public final Jid getFrom()

Gets the stanza's 'from' attribute.

8.1.2. from

The 'from' attribute specifies the JID of the sender.

Returns:

The JID.

setFrom

public final void setFrom(Jid from)

Sets the stanza's 'from' attribute, i.e. the sender.

Parameters:

from - The sender.

See Also:

()

getId

public final String getId()

Gets the stanza's 'id' attribute.

8.1.3. id

The 'id' attribute is used by the originating entity to track any response or error stanza that it might receive in relation to the generated stanza from another entity (such as an intermediate server or the intended recipient).

It is up to the originating entity whether the value of the 'id' attribute is unique only within its current stream or unique globally.

For <message/> and <presence/> stanzas, it is RECOMMENDED for the originating entity to include an 'id' attribute; for <iq/> stanzas, it is REQUIRED.

If the generated stanza includes an 'id' attribute then it is REQUIRED for the response or error stanza to also include an 'id' attribute, where the value of the 'id' attribute MUST match that of the generated stanza.

Returns:

The id.

setId

public final void setId(String id)

Sets the stanza's 'id' attribute.

Parameters:

id - The id.

See Also:

getId()

getTo

public final Jid getTo()

Gets the stanza's 'to' attribute, i.e. the recipient.

8.1.1. to

The 'to' attribute specifies the JID of the intended recipient for the stanza.

Returns:

The recipient.

setTo

public final void setTo(Jid to)

Sets the stanza's 'to' attribute, i.e. the recipient.

Parameters:

to - The recipient.

See Also:

getTo()

getLanguage

public final String getLanguage()

Gets the stanza's 'xml:lang' attribute, i.e. its language.

8.1.5. xml:lang

A stanza SHOULD possess an 'xml:lang' attribute (as defined in Section 2.12 of [XML]) if the stanza contains XML character data that is intended to be presented to a human user (as explained in [CHARSETS], "internationalization is for humans"). The value of the 'xml:lang' attribute specifies the default language of any such human-readable XML character data.

Returns:

The language.

setLanguage

public final void setLanguage(String language)

Sets the stanza's 'xml:lang' attribute, i.e. its language.

Parameters:

language - The language.

See Also:

getLanguage()

getExtension

public final <T> T getExtension(Class<T> clazz)

Gets the extension of the given type or null, if there's no such extension.

Type Parameters:

T - The extension type.

Parameters:

clazz - The extension class.

Returns:

The extension.

hasExtension

public final boolean hasExtension(Class<?> clazz)

Checks if the stanza has an extension of the given type.

Parameters:

clazz - The extension class.

Returns:

If the extension could be removed.

getError

public final StanzaError getError()

Gets the stanza's 'error' element.

8.3. Stanza Errors

Stanza-related errors are handled in a manner similar to stream errors. Unlike stream errors, stanza errors are recoverable; therefore, they do not result in termination of the XML stream and underlying TCP connection. Instead, the entity that discovers the error condition returns an error stanza, which is a stanza that:

• is of the same kind (message, presence, or IQ) as the generated stanza that triggered the error
• has a 'type' attribute set to a value of "error"
• typically swaps the 'from' and 'to' addresses of the generated stanza
• mirrors the 'id' attribute (if any) of the generated stanza that triggered the error
• contains an <error/> child element that specifies the error condition and therefore provides a hint regarding actions that the sender might be able to take in an effort to remedy the error (however, it is not always possible to remedy the error)

Returns:

The stanza error.

setError

public final void setError(StanzaError stanzaError)

Sets the stanza's 'error' element.

Parameters:

stanzaError - The stanza error.

See Also:

getError()

createError

public abstract Stanza createError(StanzaError error)

Creates an error response for this stanza.

Parameters:

error - The error which is appended to the stanza.

Returns:

The error response.

See Also:

getError()

createError

public abstract Stanza createError(Condition condition)

Creates an error response for this stanza.

Parameters:

condition - The error condition which is appended to the stanza.

Returns:

The error response.

See Also:

getError()

toString

public String toString()

Overrides:

toString in class Object