org.apache.commons.jxpath
Interface Pointer
- Cloneable, Comparable, Serializable
- BeanPointer, BeanPropertyPointer, CollectionPointer, ContainerPointer, DOMAttributePointer, DOMNodePointer, DynaBeanPointer, DynaBeanPropertyPointer, DynamicPointer, DynamicPropertyPointer, JDOMAttributePointer, JDOMNamespacePointer, JDOMNodePointer, LangAttributePointer, NamespacePointer, NodePointer, NullElementPointer, NullPointer, NullPropertyPointer, PropertyOwnerPointer, PropertyPointer, VariablePointer
public interface Pointer
extends Cloneable, Comparable, Serializable
Pointers represent locations of objects and their properties
in Java object graphs. JXPathContext has methods
(getPointer()
and (iteratePointers()
, which, given an XPath, produce Pointers for the objects
or properties described the the path. For example, ctx.getPointer
("foo/bar")
will produce a Pointer that can get and set the property
"bar" of the object which is the value of the property "foo" of the root
object. The value of ctx.getPointer("aMap/aKey[3]")
will be a
pointer to the 3'rd element of the array, which is the value for the key
"aKey" of the map, which is the value of the property "aMap" of the root
object.
$Revision: 1.9 $ $Date: 2004/02/29 14:17:42 $ String | asPath() - Returns a string that is a proper "canonical" XPath that corresponds to
this pointer.
|
Object | clone() - Pointers are cloneable
|
Object | getNode() - Returns the raw value of the object, property or collection element
this pointer represents.
|
Object | getRootNode() - Returns the node this pointer is based on.
|
Object | getValue() - Returns the value of the object, property or collection element
this pointer represents.
|
void | setValue(Object value) - Modifies the value of the object, property or collection element
this pointer represents.
|
asPath
public String asPath()
Returns a string that is a proper "canonical" XPath that corresponds to
this pointer. Consider this example:
Pointer ptr = ctx.getPointer("//employees[firstName = 'John']")
The value of
ptr.asPath()
will look something like
"/departments[2]/employees[3]"
, so, basically, it represents
the concrete location(s) of the result of a search performed by JXPath.
If an object in the pointer's path is a Dynamic Property object (like a
Map), the asPath method generates an XPath that looks like this:
"
/departments[@name = 'HR']/employees[3]"
.
clone
public Object clone()
Pointers are cloneable
getNode
public Object getNode()
Returns the raw value of the object, property or collection element
this pointer represents. Never converts the object to a
canonical type: returns it as is.
For example, for an XML element, getNode() will
return the element itself rather than the text it contains.
getRootNode
public Object getRootNode()
Returns the node this pointer is based on.
getValue
public Object getValue()
Returns the value of the object, property or collection element
this pointer represents. May convert the value to one of the
canonical InfoSet types: String, Number, Boolean, Set.
For example, in the case of an XML element, getValue() will
return the text contained by the element rather than
the element itself.
setValue
public void setValue(Object value)
Modifies the value of the object, property or collection element
this pointer represents.