Package org.jaxen

Class Context

java.lang.Object

org.jaxen.Context

All Implemented Interfaces:

Serializable

public class Context
extends Object
implements Serializable

Wrapper around implementation-specific objects used as the context of an expression evaluation.

NOTE: This class is not typically used directly, but is exposed for writers of implementation-specific XPath packages.

The Context bundles utilities together for evaluation of the expression. It wraps the provided objects for ease-of-passage through the expression AST.

Author:

bob mcwhirter

See Also:

ContextSupport, BaseXPath, XPath for dom4j, XPath for JDOM, XPath for W3C DOM, Serialized Form

Constructor Summary

Constructors

Constructor	Description
Context(ContextSupport contextSupport)	Create a new context.

Method Summary

Modifier and Type	Method	Description
Context	duplicate()	Create a type-safe shallow copy.
ContextSupport	getContextSupport()	Retrieve the ContextSupport.
Function	getFunction(String namespaceURI, String prefix, String localName)	Retrieve a Function.
Navigator	getNavigator()	Retrieve the current Navigator.
List	getNodeSet()	Retrieve the context node-set.
int	getPosition()	Retrieve current position in the context node-set.
int	getSize()	Retrieve the size of the current context node-set.
Object	getVariableValue(String namespaceURI, String prefix, String localName)	Retrieve a variable value.
void	setContextSupport(ContextSupport contextSupport)	Set the ContextSupport.
void	setNodeSet(List nodeSet)	Set the context node-set, and sets the current context size to the size of this node-set.
void	setPosition(int position)	Set the current position in the context node-set.
void	setSize(int size)	Set the current size in the context node-set.
String	translateNamespacePrefixToUri(String prefix)	Translate a namespace prefix to its URI.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Context

public Context(ContextSupport contextSupport)

Create a new context.

Parameters:

contextSupport - the context-support

Method Detail

setNodeSet

public void setNodeSet(List nodeSet)

Set the context node-set, and sets the current context size to the size of this node-set.

The actual list is stored in this object. A copy is not made. This list should not be modified in other code after calling this method.

After invoking this method, the client should immediately call setSize and setPosition.

Parameters:

nodeSet - the context node-set

getNodeSet

public List getNodeSet()

Retrieve the context node-set. This is a live list. It is not a copy. Do not modify it.

Returns:

the context node-set

setContextSupport

public void setContextSupport(ContextSupport contextSupport)

Set the ContextSupport.

Parameters:

contextSupport - the context-support

getContextSupport

public ContextSupport getContextSupport()

Retrieve the ContextSupport.

Returns:

the context-support

getNavigator

public Navigator getNavigator()

Retrieve the current Navigator.

Returns:

the navigator

translateNamespacePrefixToUri

public String translateNamespacePrefixToUri(String prefix)

Translate a namespace prefix to its URI.

Parameters:

prefix - the prefix

Returns:

the namespace URI mapped to the prefix

getVariableValue

public Object getVariableValue(String namespaceURI,
                               String prefix,
                               String localName)
                        throws UnresolvableException

Retrieve a variable value.

Parameters:

namespaceURI - the function namespace URI

prefix - the function prefix

localName - the function name

Returns:

the variable value

Throws:

UnresolvableException - if unable to locate a bound variable

getFunction

public Function getFunction(String namespaceURI,
                            String prefix,
                            String localName)
                     throws UnresolvableException

Retrieve a Function.

Parameters:

namespaceURI - the function namespace URI

prefix - the function prefix

localName - the function name

Returns:

the function object

Throws:

UnresolvableException - if unable to locate a bound function

setSize

public void setSize(int size)

Set the current size in the context node-set.

Parameters:

size - the size

getSize

public int getSize()

Retrieve the size of the current context node-set.

Returns:

the size

setPosition

public void setPosition(int position)

Set the current position in the context node-set.

Parameters:

position - the position

getPosition

public int getPosition()

Retrieve current position in the context node-set.

Returns:

the current position

duplicate

public Context duplicate()

Create a type-safe shallow copy.

Returns:

the duplicate