Modifier and Type | Field and Description |
---|---|
protected Element |
alias
the referenced element
|
protected Name |
alias_name |
protected Element |
reference |
Constructor and Description |
---|
JAlias(Name _alias_name) |
JAlias(java.lang.String _alias_name,
char separator) |
Modifier and Type | Method and Description |
---|---|
Component |
fork()
"Forks" a copy of the target component.
|
Component |
getComponent(Name _name)
Returns the component contained in the element registered in the target
component under the name
name . |
Element |
getElement(Name name)
Returns the element in the target component identified by
name ,
null if no element exists under name name . |
java.lang.Object |
getFactoryValue() |
int |
getIntValue()
Returns the value of the target component, if its class is an integer class.
|
Element |
getReference()
Returns a distinguished element referencing the target component, if any,
null otherwise.
|
java.lang.Class |
getType()
Returns the type of the target component, as a Class.
|
java.lang.Object |
getValue()
Returns the value of the target component, if its type is an object reference
type.
|
java.lang.Object |
getValue(Name _name)
Returns the value of the element registered in the target context under
the name
name . |
protected void |
initialize()
JAlias specific initialization code.
|
Component |
internalFork() |
Element |
setReference(Element _reference)
Sets an element containing the target component.
|
java.lang.String |
toString() |
protected Element alias
protected Name alias_name
protected Element reference
public JAlias(java.lang.String _alias_name, char separator)
public JAlias(Name _alias_name)
public java.lang.Class getType()
Component
public java.lang.Object getValue()
Component
If the target component is of an integral type,
NO_VALUE
} is returned.
public int getIntValue()
Component
If the target component has an object reference type, Integer.MAX_VALUE is returned.
getIntValue
in interface Component
public java.lang.Object getFactoryValue() throws JonathanException
getFactoryValue
in interface Component
JonathanException
public Element getReference()
Component
getReference
in interface Component
public Element setReference(Element _reference)
Component
setReference
in interface Component
_reference
- the new element referencing the target component.public java.lang.String toString()
toString
in class java.lang.Object
protected final void initialize()
Element
(but don't instantiate its value!). Used
used internally by JComponent
.public Component internalFork()
internalFork
in interface Forkable
public Component fork()
Component
For basic components, this operation simply duplicates the component structure, but the value is still shared.
In the configuration framework, components contain a specification of their value (in the form of an assemblage, atom, alias... description). The fork() method is used to duplicate the specification, but not the value. It may thus be used to obtain several instances of a component, using getValue() on the returned component.
When the target component is a context, the returned component is a new context, roughly containing the forked versions of the target context's components.
If the target context contains an alias, and if the target T of this alias is in the scope of the context, then the target of the forked alias is a forked instance of T. But if the target is outside the scope of the context, then the target of the forked alias is T itself. The context thus defines a set of components that will be actually duplicated, all links outside the context being preserved.
The same rule applies for assemblages, and other "container" components. For instance, consider an assemblage 'A' made of factory 'F' and configuration 'C', 'C' containing an atom 'At', an alias 'In' to At, and an alias 'Out' to a component 'K' outside 'A'. Then the forked version of 'A' is a new assemblage made of a copy of 'F' and a new configuration containing a copy 'At2' of 'At', an alias 'In2' to 'At2', and an alias 'Out2' to 'K'.
Aliases are treated specifically. Calling the fork() method on an alias is like calling the same method on its target.
public Element getElement(Name name)
Component
name
,
null if no element exists under name name
.getElement
in interface Component
name
- the name of the element to be retrieved;public final Component getComponent(Name _name)
Component
name
.
A call to getComponent(name)
is equivalent to
getElement(name)
.getComponent()
if the provided name actually
corresponds to an element. If it is not the case, null is returned.getComponent
in interface Component
_name
- the name of the element whose component is seeked;public final java.lang.Object getValue(Name _name)
Component
name
.
A call to getValue(name)
is equivalent to
getElement(name)
.getValue()
if the provided name actually
corresponds to an element. If it is not the case,
NO_VALUE
is returned.