org.apache.xalan.extensions
Class ExtensionHandlerGeneral

java.lang.Object
  org.apache.xalan.extensions.ExtensionHandler
      org.apache.xalan.extensions.ExtensionHandlerGeneral

public class ExtensionHandlerGeneral
extends ExtensionHandler

Class handling an extension namespace for XPath. Provides functions to test a function's existence and call a function

Field Summary

private static java.lang.String	BSF_MANAGER BSFManager package name
private static java.lang.String	DEFAULT_BSF_MANAGER Default BSFManager name
private java.util.Hashtable	m_elements elements of namespace
private java.lang.Object	m_engine BSF manager used to run scripts
private java.lang.reflect.Method	m_engineCall Engine call to invoke scripts
private java.util.Hashtable	m_functions functions of namespace
private java.lang.String	m_scriptSrc script source to run (if any)
private java.lang.String	m_scriptSrcURL URL of source of script (if any)
private static java.lang.String	propName Property name to load the BSFManager class
private static java.lang.Integer	ZEROINT Integer Zero

Fields inherited from class org.apache.xalan.extensions.ExtensionHandler

m_namespaceUri, m_scriptLang

Constructor Summary

ExtensionHandlerGeneral(java.lang.String namespaceUri, StringVector elemNames, StringVector funcNames, java.lang.String scriptLang, java.lang.String scriptSrcURL, java.lang.String scriptSrc, java.lang.String systemId)
Construct a new extension namespace handler given all the information needed.

Method Summary

java.lang.Object	callFunction(FuncExtFunction extFunction, java.util.Vector args, ExpressionContext exprContext) Process a call to an XPath extension function
java.lang.Object	callFunction(java.lang.String funcName, java.util.Vector args, java.lang.Object methodKey, ExpressionContext exprContext) Process a call to a function.
boolean	isElementAvailable(java.lang.String element) Tests whether a certain element name is known within this namespace.
boolean	isFunctionAvailable(java.lang.String function) Tests whether a certain function name is known within this namespace.
void	processElement(java.lang.String localPart, ElemTemplateElement element, TransformerImpl transformer, Stylesheet stylesheetTree, java.lang.Object methodKey) Process a call to this extension namespace via an element.

Methods inherited from class org.apache.xalan.extensions.ExtensionHandler

getClassForName

Methods inherited from class java.lang.Object

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

Field Detail

m_scriptSrc

private java.lang.String m_scriptSrc

script source to run (if any)

m_scriptSrcURL

private java.lang.String m_scriptSrcURL

URL of source of script (if any)

m_functions

private java.util.Hashtable m_functions

functions of namespace

m_elements

private java.util.Hashtable m_elements

elements of namespace

m_engine

private java.lang.Object m_engine

BSF manager used to run scripts

m_engineCall

private java.lang.reflect.Method m_engineCall

Engine call to invoke scripts

BSF_MANAGER

private static java.lang.String BSF_MANAGER

BSFManager package name

DEFAULT_BSF_MANAGER

private static final java.lang.String DEFAULT_BSF_MANAGER

Default BSFManager name

See Also:

Constant Field Values

propName

private static final java.lang.String propName

Property name to load the BSFManager class

See Also:

Constant Field Values

ZEROINT

private static final java.lang.Integer ZEROINT

Integer Zero

Constructor Detail

ExtensionHandlerGeneral

public ExtensionHandlerGeneral(java.lang.String namespaceUri,
                               StringVector elemNames,
                               StringVector funcNames,
                               java.lang.String scriptLang,
                               java.lang.String scriptSrcURL,
                               java.lang.String scriptSrc,
                               java.lang.String systemId)
                        throws javax.xml.transform.TransformerException

Construct a new extension namespace handler given all the information needed.

Parameters:

namespaceUri - the extension namespace URI that I'm implementing

elemNames - Vector of element names

funcNames - string containing list of functions of extension NS

scriptLang - Scripting language of implementation

scriptSrcURL - URL of source script

scriptSrc - the actual script code (if any)

systemId -

Throws:

javax.xml.transform.TransformerException

Method Detail

isFunctionAvailable

public boolean isFunctionAvailable(java.lang.String function)

Tests whether a certain function name is known within this namespace.

Specified by:

isFunctionAvailable in class ExtensionHandler

Parameters:

function - name of the function being tested

Returns:

true if its known, false if not.

isElementAvailable

public boolean isElementAvailable(java.lang.String element)

Tests whether a certain element name is known within this namespace.

Specified by:

isElementAvailable in class ExtensionHandler

Parameters:

element - name of the element being tested

Returns:

true if its known, false if not.

callFunction

public java.lang.Object callFunction(java.lang.String funcName,
                                     java.util.Vector args,
                                     java.lang.Object methodKey,
                                     ExpressionContext exprContext)
                              throws javax.xml.transform.TransformerException

Process a call to a function.

Specified by:

callFunction in class ExtensionHandler

Parameters:

funcName - Function name.

args - The arguments of the function call.

methodKey - A key that uniquely identifies this class and method call.

exprContext - The context in which this expression is being executed.

Returns:

the return value of the function evaluation.

Throws:

javax.xml.transform.TransformerException - if parsing trouble

callFunction

public java.lang.Object callFunction(FuncExtFunction extFunction,
                                     java.util.Vector args,
                                     ExpressionContext exprContext)
                              throws javax.xml.transform.TransformerException

Process a call to an XPath extension function

Specified by:

callFunction in class ExtensionHandler

Parameters:

extFunction - The XPath extension function

args - The arguments of the function call.

exprContext - The context in which this expression is being executed.

Returns:

the return value of the function evaluation.

Throws:

javax.xml.transform.TransformerException

processElement

public void processElement(java.lang.String localPart,
                           ElemTemplateElement element,
                           TransformerImpl transformer,
                           Stylesheet stylesheetTree,
                           java.lang.Object methodKey)
                    throws javax.xml.transform.TransformerException,
                           java.io.IOException

Process a call to this extension namespace via an element. As a side effect, the results are sent to the TransformerImpl's result tree.

Specified by:

processElement in class ExtensionHandler

Parameters:

localPart - Element name's local part.

element - The extension element being processed.

transformer - Handle to TransformerImpl.

stylesheetTree - The compiled stylesheet tree.

methodKey - A key that uniquely identifies this class and method call.

Throws:

XSLProcessorException - thrown if something goes wrong while running the extension handler.

MalformedURLException - if loading trouble

FileNotFoundException - if loading trouble

java.io.IOException - if loading trouble

javax.xml.transform.TransformerException - if parsing trouble