WebLogic Server 6.0sp2 API Reference

weblogic.apache.xalan.xpath
Class XSLTJavaClassEngine

weblogic.apache.xalan.xpath.XSLTJavaClassEngine

public class XSLTJavaClassEngine

implements ExtensionFunctionHandler.ExtensionLiaison

This is a custom scripting engine for the XSLT processor's needs of calling into Java objects.

This class is based on an implementation from the Apache XML Project. In future releases the XML parser, XSLT processor, and associated classes will likely be updated to be based on a later version of the Apache implementations. Since Apache does not guarantee backwards compatibility between versions of their software, we cannot guarantee backwards compatibility of any of the classes contained in the weblogic.apache package or sub-packages.

Author:

Sanjiva Weerawarana (sanjiva@watson.ibm.com)
Copyright © 2001 BEA Systems, Inc. All Rights Reserved.

Field Summary

protected static boolean	bsfInitialized Tell if we've already initialized the bsf engine.
java.lang.Class	classObject
protected boolean	componentStarted
protected boolean	hasCalledCTor
java.lang.Object	javaObject
protected static java.lang.Boolean	m_bsfInitSynch
protected com.ibm.bsf.BSFManager	mgr
java.lang.String	scriptLang
java.lang.String	scriptSrc
java.lang.String	scriptSrcURL

Constructor Summary

XSLTJavaClassEngine()

Method Summary

java.lang.Object	call(java.lang.Object object, java.lang.String method, java.lang.Object[] args) call the named method on the object that was loaded by eval.
java.lang.Object	callFunction(java.lang.String funcName, java.util.Vector args, java.lang.Object methodKey, java.lang.Class javaClass) Process a call to a function.
java.lang.Object	callJava(java.lang.Object object, java.lang.String method, java.lang.Object[] args, java.lang.Object methodKey) call the named method on the object that was loaded by eval.
void	checkInit()
java.lang.Object	eval(java.lang.String source, int lineNo, int columnNo, java.lang.Object oscript) This is used by an application to evaluate an object containing some expression - clearly not possible for compiled code ..
void	setScript(java.lang.String lang, java.lang.String srcURL, java.lang.String scriptSrc) Set the script data for this extension NS.
void	startupComponent(java.lang.Class classObj) Start the component up by executing any script that needs to run at startup time.

Field Detail

scriptLang

public java.lang.String scriptLang

scriptSrcURL

public java.lang.String scriptSrcURL

scriptSrc

public java.lang.String scriptSrc

hasCalledCTor

protected boolean hasCalledCTor

javaObject

public java.lang.Object javaObject

classObject

public java.lang.Class classObject

mgr

protected com.ibm.bsf.BSFManager mgr

componentStarted

protected boolean componentStarted

bsfInitialized

protected static boolean bsfInitialized

Tell if we've already initialized the bsf engine.

m_bsfInitSynch

protected static java.lang.Boolean m_bsfInitSynch

Constructor Detail

XSLTJavaClassEngine

public XSLTJavaClassEngine()

Method Detail

eval

public java.lang.Object eval(java.lang.String source,
                             int lineNo,
                             int columnNo,
                             java.lang.Object oscript)
                      throws weblogic.apache.xalan.xpath.BSFException

This is used by an application to evaluate an object containing some expression - clearly not possible for compiled code ..

call

public java.lang.Object call(java.lang.Object object,
                             java.lang.String method,
                             java.lang.Object[] args)
                      throws weblogic.apache.xalan.xpath.BSFException

call the named method on the object that was loaded by eval. The method selection stuff is very XSLT-specific, hence the custom engine.

Parameters:

object - ignored - should always be null

setScript

public void setScript(java.lang.String lang,
                      java.lang.String srcURL,
                      java.lang.String scriptSrc)

Set the script data for this extension NS. If srcURL is !null then the script body is read from that URL. If not the scriptSrc is used as the src. This method does not actually execute anything - that's done when the component is first hit by the user by an element or a function call.

Specified by:

setScript in interface ExtensionFunctionHandler.ExtensionLiaison

Parameters:

lang - language of the script.

srcURL - value of src attribute (if any) - treated as a URL or a classname depending on the value of lang. If srcURL is not null, then scriptSrc is ignored.

scriptSrc - the actual script code (if any)

callJava

public java.lang.Object callJava(java.lang.Object object,
                                 java.lang.String method,
                                 java.lang.Object[] args,
                                 java.lang.Object methodKey)
                          throws XPathException

call the named method on the object that was loaded by eval. The method selection stuff is very XSLT-specific, hence the custom engine.

Specified by:

callJava in interface ExtensionFunctionHandler.ExtensionLiaison

Parameters:

object - ignored - should always be null

callFunction

public java.lang.Object callFunction(java.lang.String funcName,
                                     java.util.Vector args,
                                     java.lang.Object methodKey,
                                     java.lang.Class javaClass)
                              throws XPathException

Process a call to a function.

Specified by:

callFunction in interface ExtensionFunctionHandler.ExtensionLiaison

Parameters:

funcName - Function name.

args - The arguments of the function call.

Returns:

the return value of the function evaluation.

Throws:

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

MalformedURLException - if loading trouble

java.io.FileNotFoundException - if loading trouble

java.io.IOException - if loading trouble

org.xml.sax.SAXException - if parsing trouble

checkInit

public void checkInit()
               throws XPathProcessorException

Specified by:

checkInit in interface ExtensionFunctionHandler.ExtensionLiaison

startupComponent

public void startupComponent(java.lang.Class classObj)
                      throws XPathProcessorException

Start the component up by executing any script that needs to run at startup time. This needs to happen before any functions can be called on the component.

Specified by:

startupComponent in interface ExtensionFunctionHandler.ExtensionLiaison

Throws:

XPathProcessorException - if something bad happens.