mirror of
https://github.com/vanitasvitae/Smack.git
synced 2024-11-18 02:02:04 +01:00
33 lines
1 KiB
Markdown
33 lines
1 KiB
Markdown
General Rules
|
|
=============
|
|
|
|
All classes which subclass `TopLevelStreamElement` and `ExtensionElement` must either
|
|
|
|
1. be immutable (and ideally provide a Builder)
|
|
2. implement `TypedCloneable`
|
|
|
|
and must be `Serializable`.
|
|
The reason that it must be either 1. or 2. is that it makes no sense to clone an inmutable instance.
|
|
The preferred option is 1.
|
|
|
|
Note that there is legacy code in Smack which does not follow these rules. Patches are welcome.
|
|
|
|
ExtensionElement
|
|
================
|
|
|
|
Extension elements are XML elements that are used in various parts and levels of stanzas.
|
|
|
|
The static `from(Stanza)` Method
|
|
--------------------------------
|
|
|
|
Every ExtensionElement class must have a static `from()` method that retrieves that extension for a given Stanza (if any).
|
|
|
|
Sample Code
|
|
|
|
```java
|
|
public static RSMSet from(Stanza) {
|
|
return packet.getExtension(ELEMENT, NAMESPACE);
|
|
}
|
|
```
|
|
|
|
Sometimes certain ExtensionElement's are only found in one stanza type, in that case, specify the parameter type. For example `public static CarbonExtension getFrom(Message)`.
|