/*
* $Header: /home/cvs/jakarta-commons-sandbox/jelly/src/java/org/apache/commons/jelly/parser/XMLParser.java,v 1.28 2002/09/05 16:42:47 jstrachan Exp $
* $Revision: 1.28 $
* $Date: 2002/09/05 16:42:47 $
*
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 1999-2002 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* $Id: XMLParser.java,v 1.28 2002/09/05 16:42:47 jstrachan Exp $
*/
package org.apache.commons.jelly.parser;
import java.io.File;
import java.io.FileReader;
import java.io.InputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Reader;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.EmptyStackException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.apache.commons.collections.ArrayStack;
import org.apache.commons.jelly.JellyContext;
import org.apache.commons.jelly.Script;
import org.apache.commons.jelly.Tag;
import org.apache.commons.jelly.TagLibrary;
import org.apache.commons.jelly.impl.CompositeTextScriptBlock;
import org.apache.commons.jelly.impl.ExpressionScript;
import org.apache.commons.jelly.impl.StaticTag;
import org.apache.commons.jelly.impl.DynaTagScript;
import org.apache.commons.jelly.impl.ScriptBlock;
import org.apache.commons.jelly.impl.StaticTagScript;
import org.apache.commons.jelly.impl.TagFactory;
import org.apache.commons.jelly.impl.TagScript;
import org.apache.commons.jelly.impl.TextScript;
import org.apache.commons.jelly.expression.CompositeExpression;
import org.apache.commons.jelly.expression.ConstantExpression;
import org.apache.commons.jelly.expression.Expression;
import org.apache.commons.jelly.expression.ExpressionFactory;
import org.apache.commons.jelly.expression.jexl.JexlExpressionFactory;
import org.apache.commons.jelly.tags.core.CoreTagLibrary;
import org.apache.commons.jelly.tags.xml.XMLTagLibrary;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.InputSource;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.XMLReader;
/** <p><code>XMLParser</code> parses the XML Jelly format.
* The SAXParser and XMLReader portions of this code come from Digester.</p>
*
* @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
* @version $Revision: 1.28 $
*/
public class XMLParser extends DefaultHandler {
/** JellyContext which is used to locate tag libraries*/
private JellyContext context = new JellyContext();
/** the expression factory used to evaluate tag attributes */
private ExpressionFactory expressionFactory;
/** The current script block */
private ScriptBlock script;
/** The current, parent tagScript */
private TagScript tagScript;
/** The stack of body scripts. */
private ArrayStack scriptStack = new ArrayStack();
/** The stack of tagScripts - use ArrayList as it allows null. */
private ArrayList tagScriptStack = new ArrayList();
/** The current text buffer where non-custom tags get written */
private StringBuffer textBuffer;
/**
* The class loader to use for instantiating application objects.
* If not specified, the context class loader, or the class loader
* used to load XMLParser itself, is used, based on the value of the
* <code>useContextClassLoader</code> variable.
*/
protected ClassLoader classLoader = null;
/**
* Do we want to use the Context ClassLoader when loading classes
* for instantiating new objects? Default is <code>false</code>.
*/
protected boolean useContextClassLoader = false;
/**
* The application-supplied error handler that is notified when parsing
* warnings, errors, or fatal errors occur.
*/
protected ErrorHandler errorHandler = null;
/**
* The SAXParserFactory that is created the first time we need it.
*/
protected static SAXParserFactory factory = null;
/**
* The SAXParser we will use to parse the input stream.
*/
protected SAXParser parser = null;
/**
* The XMLReader used to parse digester rules.
*/
protected XMLReader reader = null;
/**
* The Locator associated with our parser.
*/
protected Locator locator = null;
/**
* Registered namespaces we are currently processing. The key is the
* namespace prefix that was declared in the document. The value is an
* ArrayStack of the namespace URIs this prefix has been mapped to --
* the top Stack element is the most current one. (This architecture
* is required because documents can declare nested uses of the same
* prefix for different Namespace URIs).
*/
protected HashMap namespaces = new HashMap();
/** The Map of the namespace prefix -> URIs defined for the current element */
private Map elementNamespaces;
/**
* The name of the file being parsed that is passed to the TagScript objects
* for error reporting
*/
private String fileName;
/**
* Do we want to use a validating parser?
*/
protected boolean validating = false;
/** Flag to indicate if this object has been configured */
private boolean configured;
/**
* The Log to which logging calls will be made.
*/
private Log log = LogFactory.getLog(XMLParser.class);
/**
* Construct a new XMLParser with default properties.
*/
public XMLParser() {
}
/**
* Construct a new XMLParser, allowing a SAXParser to be passed in. This
* allows XMLParser to be used in environments which are unfriendly to
* JAXP1.1 (such as WebLogic 6.0). Thanks for the request to change go to
* James House (james@interobjective.com). This may help in places where
* you are able to load JAXP 1.1 classes yourself.
*/
public XMLParser(SAXParser parser) {
this.parser = parser;
}
/**
* Construct a new XMLParser, allowing an XMLReader to be passed in. This
* allows XMLParser to be used in environments which are unfriendly to
* JAXP1.1 (such as WebLogic 6.0). Note that if you use this option you
* have to configure namespace and validation support yourself, as these
* properties only affect the SAXParser and emtpy constructor.
*/
public XMLParser(XMLReader reader) {
this.reader = reader;
}
/**
* Parse the content of the specified file using this XMLParser. Returns
* the root element from the object stack (if any).
*
* @param file File containing the XML data to be parsed
*
* @exception IOException if an input/output error occurs
* @exception SAXException if a parsing exception occurs
*/
public Script parse(File file) throws IOException, SAXException {
ensureConfigured();
this.fileName = file.toString();
getXMLReader().parse(new InputSource(new FileReader(file)));
return script;
}
/**
* Parse the content of the specified input source using this XMLParser.
* Returns the root element from the object stack (if any).
*
* @param input Input source containing the XML data to be parsed
*
* @exception IOException if an input/output error occurs
* @exception SAXException if a parsing exception occurs
*/
public Script parse(InputSource input) throws IOException, SAXException {
ensureConfigured();
this.fileName = input.getSystemId();
getXMLReader().parse(input);
return script;
}
/**
* Parse the content of the specified input stream using this XMLParser.
* Returns the root element from the object stack (if any).
*
* @param input Input stream containing the XML data to be parsed
*
* @exception IOException if an input/output error occurs
* @exception SAXException if a parsing exception occurs
*/
public Script parse(InputStream input) throws IOException, SAXException {
ensureConfigured();
this.fileName = null;
getXMLReader().parse(new InputSource(input));
return script;
}
/**
* Parse the content of the specified reader using this XMLParser.
* Returns the root element from the object stack (if any).
*
* @param reader Reader containing the XML data to be parsed
*
* @exception IOException if an input/output error occurs
* @exception SAXException if a parsing exception occurs
*/
public Script parse(Reader reader) throws IOException, SAXException {
ensureConfigured();
this.fileName = null;
getXMLReader().parse(new InputSource(reader));
return script;
}
/**
* Parse the content of the specified URI using this XMLParser.
* Returns the root element from the object stack (if any).
*
* @param uri URI containing the XML data to be parsed
*
* @exception IOException if an input/output error occurs
* @exception SAXException if a parsing exception occurs
*/
public Script parse(String uri) throws IOException, SAXException {
ensureConfigured();
this.fileName = uri;
getXMLReader().parse(uri);
return script;
}
/**
* Return the currently mapped namespace URI for the specified prefix,
* if any; otherwise return <code>null</code>. These mappings come and
* go dynamically as the document is parsed.
*
* @param prefix Prefix to look up
*/
public String findNamespaceURI(String prefix) {
ArrayStack stack = (ArrayStack) namespaces.get(prefix);
if (stack == null) {
return (null);
}
try {
return ((String) stack.peek());
}
catch (EmptyStackException e) {
return (null);
}
}
// Properties
//-------------------------------------------------------------------------
public JellyContext getContext() {
return context;
}
public void setContext(JellyContext context) {
this.context = context;
}
/**
* Return the class loader to be used for instantiating application objects
* when required. This is determined based upon the following rules:
* <ul>
* <li>The class loader set by <code>setClassLoader()</code>, if any</li>
* <li>The thread context class loader, if it exists and the
* <code>useContextClassLoader</code> property is set to true</li>
* <li>The class loader used to load the XMLParser class itself.
* </ul>
*/
public ClassLoader getClassLoader() {
if (this.classLoader != null) {
return (this.classLoader);
}
if (this.useContextClassLoader) {
ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
if (classLoader != null) {
return (classLoader);
}
}
return (this.getClass().getClassLoader());
}
/**
* Set the class loader to be used for instantiating application objects
* when required.
*
* @param classLoader The new class loader to use, or <code>null</code>
* to revert to the standard rules
*/
public void setClassLoader(ClassLoader classLoader) {
this.classLoader = classLoader;
}
/**
* Return the boolean as to whether the context classloader should be used.
*/
public boolean getUseContextClassLoader() {
return useContextClassLoader;
}
/**
* Determine whether to use the Context ClassLoader (the one found by
* calling <code>Thread.currentThread().getContextClassLoader()</code>)
* to resolve/load classes. If not
* using Context ClassLoader, then the class-loading defaults to
* using the calling-class' ClassLoader.
*
* @param boolean determines whether to use JellyContext ClassLoader.
*/
public void setUseContextClassLoader(boolean use) {
useContextClassLoader = use;
}
/**
* Return the error handler for this XMLParser.
*/
public ErrorHandler getErrorHandler() {
return (this.errorHandler);
}
/**
* Set the error handler for this XMLParser.
*
* @param errorHandler The new error handler
*/
public void setErrorHandler(ErrorHandler errorHandler) {
this.errorHandler = errorHandler;
}
/**
* Return the current Logger associated with this instance of the XMLParser
*/
public Log getLogger() {
return log;
}
/**
* Set the current logger for this XMLParser.
*/
public void setLogger(Log log) {
this.log = log;
}
/** @return the expression factory used to evaluate tag attributes */
public ExpressionFactory getExpressionFactory() {
if (expressionFactory == null) {
expressionFactory = createExpressionFactory();
}
return expressionFactory;
}
/** Sets the expression factory used to evaluate tag attributes */
public void setExpressionFactory(ExpressionFactory expressionFactory) {
this.expressionFactory = expressionFactory;
}
/**
* Return the SAXParser we will use to parse the input stream. If there
* is a problem creating the parser, return <code>null</code>.
*/
public SAXParser getParser() {
// Return the parser we already created (if any)
if (parser != null) {
return (parser);
}
// Create and return a new parser
synchronized (this) {
try {
if (factory == null) {
factory = SAXParserFactory.newInstance();
}
factory.setNamespaceAware(true);
factory.setValidating(validating);
parser = factory.newSAXParser();
return (parser);
}
catch (Exception e) {
log.error("XMLParser.getParser: ", e);
return (null);
}
}
}
/**
* By setting the reader in the constructor, you can bypass JAXP and
* be able to use digester in Weblogic 6.0.
*
* @deprecated Use getXMLReader() instead, which can throw a
* SAXException if the reader cannot be instantiated
*/
public XMLReader getReader() {
try {
return (getXMLReader());
}
catch (SAXException e) {
log.error("Cannot get XMLReader", e);
return (null);
}
}
/**
* Return the XMLReader to be used for parsing the input document.
*
* @exception SAXException if no XMLReader can be instantiated
*/
public synchronized XMLReader getXMLReader() throws SAXException {
if (reader == null) {
reader = getParser().getXMLReader();
}
//set up the parse
reader.setContentHandler(this);
reader.setDTDHandler(this);
//reader.setEntityResolver(this);
reader.setErrorHandler(this);
return reader;
}
/**
* Return the validating parser flag.
*/
public boolean getValidating() {
return (this.validating);
}
/**
* Set the validating parser flag. This must be called before
* <code>parse()</code> is called the first time.
*
* @param validating The new validating parser flag.
*/
public void setValidating(boolean validating) {
this.validating = validating;
}
// ContentHandler interface
//-------------------------------------------------------------------------
/**
* Process notification of the beginning of the document being reached.
*
* @exception SAXException if a parsing error is to be reported
*/
public void startDocument() throws SAXException {
script = new ScriptBlock();
textBuffer = new StringBuffer();
tagScript = null;
scriptStack.clear();
tagScriptStack.clear();
}
/**
* Process notification of the end of the document being reached.
*
* @exception SAXException if a parsing error is to be reported
*/
public void endDocument() throws SAXException {
textBuffer = null;
}
/**
* Process notification of the start of an XML element being reached.
*
* @param uri The Namespace URI, or the empty string if the element
* has no Namespace URI or if Namespace processing is not being performed.
* @param localName The local name (without prefix), or the empty
* string if Namespace processing is not being performed.
* @param qName The qualified name (with prefix), or the empty
* string if qualified names are not available.\
* @param list The attributes attached to the element. If there are
* no attributes, it shall be an empty Attributes object.
* @exception SAXException if a parsing error is to be reported
*/
public void startElement(
String namespaceURI,
String localName,
String qName,
Attributes list)
throws SAXException {
try {
// add check to ensure namespace URI is "" for no namespace
if ( namespaceURI == null ) {
namespaceURI = "";
}
// if this is a tag then create a script to run it
// otherwise pass the text to the current body
TagScript parentTagScript = tagScript;
tagScript = createTag(namespaceURI, localName, list);
if (tagScript == null) {
tagScript = createStaticTag(namespaceURI, localName, qName, list);
}
tagScriptStack.add(tagScript);
if (tagScript != null) {
// set parent relationship...
tagScript.setParent(parentTagScript);
// set the namespace Map
if ( elementNamespaces != null ) {
tagScript.setNamespacesMap( elementNamespaces );
elementNamespaces = null;
}
// set the line number details
if ( locator != null ) {
tagScript.setLocator(locator);
}
// sets the file name element names
tagScript.setFileName(fileName);
tagScript.setElementName(qName);
if (textBuffer.length() > 0) {
addTextScript(textBuffer.toString());
textBuffer.setLength(0);
}
script.addScript(tagScript);
// start a new body
scriptStack.push(script);
script = new ScriptBlock();
tagScript.setTagBody(script);
}
else {
// XXXX: might wanna handle empty elements later...
textBuffer.append("<");
textBuffer.append(qName);
int size = list.getLength();
for (int i = 0; i < size; i++) {
textBuffer.append(" ");
textBuffer.append(list.getQName(i));
textBuffer.append("=");
textBuffer.append("\"");
textBuffer.append(list.getValue(i));
textBuffer.append("\"");
}
textBuffer.append(">");
}
}
catch (SAXException e) {
throw e;
}
catch (Exception e) {
log.error( "Caught exception: " + e, e );
throw new SAXException( "Runtime Exception: " + e, e );
}
}
/**
* Process notification of character data received from the body of
* an XML element.
*
* @param buffer The characters from the XML document
* @param start Starting offset into the buffer
* @param length Number of characters from the buffer
*
* @exception SAXException if a parsing error is to be reported
*/
public void characters(char buffer[], int start, int length)
throws SAXException {
textBuffer.append(buffer, start, length);
}
/**
* Process notification of the end of an XML element being reached.
*
* @param uri - The Namespace URI, or the empty string if the
* element has no Namespace URI or if Namespace processing is not
* being performed.
* @param localName - The local name (without prefix), or the empty
* string if Namespace processing is not being performed.
* @param qName - The qualified XML 1.0 name (with prefix), or the
* empty string if qualified names are not available.
* @exception SAXException if a parsing error is to be reported
*/
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
try {
tagScript = (TagScript) tagScriptStack.remove(tagScriptStack.size() - 1);
if (tagScript != null) {
if (textBuffer.length() > 0) {
addTextScript(textBuffer.toString());
textBuffer.setLength(0);
}
script = (ScriptBlock) scriptStack.pop();
}
else {
textBuffer.append("</");
textBuffer.append(qName);
textBuffer.append(">");
}
// now lets set the parent tag variable
if ( tagScriptStack.isEmpty() ) {
tagScript = null;
}
else {
tagScript = (TagScript) tagScriptStack.get(tagScriptStack.size() - 1);
}
}
catch (SAXException e) {
throw e;
}
catch (Exception e) {
log.error( "Caught exception: " + e, e );
throw new SAXException( "Runtime Exception: " + e, e );
}
}
/**
* Process notification that a namespace prefix is coming in to scope.
*
* @param prefix Prefix that is being declared
* @param namespaceURI Corresponding namespace URI being mapped to
*
* @exception SAXException if a parsing error is to be reported
*/
public void startPrefixMapping(String prefix, String namespaceURI)
throws SAXException {
// Register this prefix mapping
ArrayStack stack = (ArrayStack) namespaces.get(prefix);
if (stack == null) {
stack = new ArrayStack();
namespaces.put(prefix, stack);
}
stack.push(namespaceURI);
if ( elementNamespaces == null ) {
elementNamespaces = new HashMap();
}
elementNamespaces.put(prefix, namespaceURI);
}
/**
* Process notification that a namespace prefix is going out of scope.
*
* @param prefix Prefix that is going out of scope
*
* @exception SAXException if a parsing error is to be reported
*/
public void endPrefixMapping(String prefix) throws SAXException {
// Deregister this prefix mapping
ArrayStack stack = (ArrayStack) namespaces.get(prefix);
if (stack == null) {
return;
}
try {
stack.pop();
if (stack.empty()) {
namespaces.remove(prefix);
}
}
catch (EmptyStackException e) {
throw createSAXException("endPrefixMapping popped too many times");
}
}
/**
* Process notification of ignorable whitespace received from the body of
* an XML element.
*
* @param buffer The characters from the XML document
* @param start Starting offset into the buffer
* @param length Number of characters from the buffer
*
* @exception SAXException if a parsing error is to be reported
*/
public void ignorableWhitespace(char buffer[], int start, int len)
throws SAXException {
; // No processing required
}
/**
* Process notification of a processing instruction that was encountered.
*
* @param target The processing instruction target
* @param data The processing instruction data (if any)
*
* @exception SAXException if a parsing error is to be reported
*/
public void processingInstruction(String target, String data)
throws SAXException {
; // No processing is required
}
/**
* Set the document locator associated with our parser.
*
* @param locator The new locator
*/
public void setDocumentLocator(Locator locator) {
this.locator = locator;
}
/**
* Process notification of a skipped entity.
*
* @param name Name of the skipped entity
*
* @exception SAXException if a parsing error is to be reported
*/
public void skippedEntity(String name) throws SAXException {
; // No processing required
}
// DTDHandler interface
//-------------------------------------------------------------------------
/**
* Receive notification of a notation declaration event.
*
* @param name The notation name
* @param publicId The public identifier (if any)
* @param systemId The system identifier (if any)
*/
public void notationDecl(String name, String publicId, String systemId) {
}
/**
* Receive notification of an unparsed entity declaration event.
*
* @param name The unparsed entity name
* @param publicId The public identifier (if any)
* @param systemId The system identifier (if any)
* @param notation The name of the associated notation
*/
public void unparsedEntityDecl(
String name,
String publicId,
String systemId,
String notation) {
}
// ErrorHandler interface
//-------------------------------------------------------------------------
/**
* Forward notification of a parsing error to the application supplied
* error handler (if any).
*
* @param exception The error information
*
* @exception SAXException if a parsing exception occurs
*/
public void error(SAXParseException exception) throws SAXException {
log.error(
"Parse Error at line "
+ exception.getLineNumber()
+ " column "
+ exception.getColumnNumber()
+ ": "
+ exception.getMessage(),
exception);
if (errorHandler != null) {
errorHandler.error(exception);
}
}
/**
* Forward notification of a fatal parsing error to the application
* supplied error handler (if any).
*
* @param exception The fatal error information
*
* @exception SAXException if a parsing exception occurs
*/
public void fatalError(SAXParseException exception) throws SAXException {
log.error(
"Parse Fatal Error at line "
+ exception.getLineNumber()
+ " column "
+ exception.getColumnNumber()
+ ": "
+ exception.getMessage(),
exception);
if (errorHandler != null) {
errorHandler.fatalError(exception);
}
}
/**
* Forward notification of a parse warning to the application supplied
* error handler (if any).
*
* @param exception The warning information
*
* @exception SAXException if a parsing exception occurs
*/
public void warning(SAXParseException exception) throws SAXException {
log.error(
"Parse Warning at line "
+ exception.getLineNumber()
+ " column "
+ exception.getColumnNumber()
+ ": "
+ exception.getMessage(),
exception);
if (errorHandler != null) {
errorHandler.warning(exception);
}
}
// Implementation methods
//-------------------------------------------------------------------------
/**
* If this object has not been configured then register the default
* namespaces
*/
private void ensureConfigured() {
if (!configured) {
configure();
configured = true;
}
}
/**
* This method is called only once before parsing occurs
* which allows tag libraries to be registered and so forth
*/
protected void configure() {
// load the properties file of libraries available
InputStream in = null;
URL url =
getClassLoader().getResource("org/apache/commons/jelly/jelly.properties");
if (url != null) {
log.debug("Loading Jelly default tag libraries from: " + url);
Properties properties = new Properties();
try {
in = url.openStream();
properties.load(in);
for (Iterator iter = properties.entrySet().iterator(); iter.hasNext();) {
Map.Entry entry = (Map.Entry) iter.next();
String uri = (String) entry.getKey();
String className = (String) entry.getValue();
String libraryURI = "jelly:" + uri;
// don't overload any Mock Tags already
if ( context.getTagLibrary(libraryURI) == null ) {
context.registerTagLibrary(libraryURI, className);
}
}
}
catch (IOException e) {
log.error("Could not load jelly properties from: " + url + ". Reason: " + e, e);
}
finally {
try {
in.close();
}
catch (Exception e) {
// ignore
}
}
}
}
/**
* Factory method to create new Tag script for the given namespaceURI and name or
* return null if this is not a custom Tag.
*/
protected TagScript createTag(
String namespaceURI,
String localName,
Attributes list)
throws SAXException {
try {
// use the URI to load a taglib
TagLibrary taglib = context.getTagLibrary(namespaceURI);
if (taglib == null) {
if (namespaceURI != null && namespaceURI.startsWith("jelly:")) {
String uri = namespaceURI.substring(6);
// try to find the class on the claspath
try {
Class taglibClass = getClassLoader().loadClass(uri);
taglib = (TagLibrary) taglibClass.newInstance();
context.registerTagLibrary(namespaceURI, taglib);
}
catch (ClassNotFoundException e) {
log.warn("Could not load class: " + uri + " so disabling the taglib");
}
}
}
if (taglib != null) {
TagScript script = taglib.createTagScript(localName, list);
if ( script != null ) {
// now iterate through through the expressions
int size = list.getLength();
for (int i = 0; i < size; i++) {
String attributeName = list.getLocalName(i);
String attributeValue = list.getValue(i);
Expression expression =
taglib.createExpression(
getExpressionFactory(),
localName,
attributeName,
attributeValue);
if (expression == null) {
expression = createConstantExpression(localName, attributeName, attributeValue);
}
script.addAttribute(attributeName, expression);
}
}
return script;
}
return null;
}
catch (Exception e) {
log.warn(
"Could not create taglib or URI: " + namespaceURI + " tag name: " + localName,
e);
throw createSAXException(e);
}
catch (Throwable e) {
log.warn(
"Could not create taglib or URI: " + namespaceURI + " tag name: " + localName,
e);
return null;
}
}
/**
* Factory method to create a static Tag that represents some static content.
*/
protected TagScript createStaticTag(
final String namespaceURI,
final String localName,
final String qName,
Attributes list)
throws SAXException {
try {
StaticTag tag = new StaticTag( namespaceURI, localName, qName );
StaticTagScript script = new StaticTagScript(
new TagFactory() {
public Tag createTag() {
return new StaticTag( namespaceURI, localName, qName );
}
}
);
// now iterate through through the expressions
int size = list.getLength();
for (int i = 0; i < size; i++) {
String attributeName = list.getLocalName(i);
String attributeValue = list.getValue(i);
Expression expression = CompositeExpression.parse(
attributeValue, getExpressionFactory()
);
script.addAttribute(attributeName, expression);
}
return script;
}
catch (Exception e) {
log.warn(
"Could not create static tag for URI: "
+ namespaceURI
+ " tag name: "
+ localName,
e);
throw createSAXException(e);
}
}
/**
* Adds the text to the current script block parsing any embedded
* expressions inot ExpressionScript objects.
*/
protected void addTextScript(String text) throws Exception {
Expression expression =
CompositeExpression.parse(text, getExpressionFactory());
addExpressionScript(script, expression);
}
/**
* Adds the given Expression object to the current Script.
*/
protected void addExpressionScript(ScriptBlock script, Expression expression) {
if ( expression instanceof ConstantExpression ) {
ConstantExpression constantExpression
= (ConstantExpression) expression;
Object value = constantExpression.getValue();
if ( value != null ) {
script.addScript(new TextScript( value.toString() ));
}
}
else
if ( expression instanceof CompositeExpression ) {
CompositeTextScriptBlock newBlock = new CompositeTextScriptBlock();
script.addScript(newBlock);
CompositeExpression compositeExpression
= (CompositeExpression) expression;
Iterator iter = compositeExpression.getExpressions().iterator();
while (iter.hasNext()) {
addExpressionScript( newBlock, (Expression) iter.next() );
}
}
else {
script.addScript(new ExpressionScript(expression));
}
}
protected Expression createConstantExpression(
String tagName,
String attributeName,
String attributeValue)
throws Exception {
return new ConstantExpression(attributeValue);
}
protected ExpressionFactory createExpressionFactory() {
return new JexlExpressionFactory();
}
/**
* Create a SAX exception which also understands about the location in
* the file where the exception occurs
*
* @return the new exception
*/
protected SAXException createSAXException(String message, Exception e) {
log.warn("Underlying exception: " + e);
e.printStackTrace();
if (locator != null) {
String error =
"Error at ("
+ locator.getLineNumber()
+ ", "
+ locator.getColumnNumber()
+ ": "
+ message;
if (e != null) {
return new SAXParseException(error, locator, e);
}
else {
return new SAXParseException(error, locator);
}
}
log.error("No Locator!");
if (e != null) {
return new SAXException(message, e);
}
else {
return new SAXException(message);
}
}
/**
* Create a SAX exception which also understands about the location in
* the digester file where the exception occurs
*
* @return the new exception
*/
protected SAXException createSAXException(Exception e) {
return createSAXException(e.getMessage(), e);
}
/**
* Create a SAX exception which also understands about the location in
* the digester file where the exception occurs
*
* @return the new exception
*/
protected SAXException createSAXException(String message) {
return createSAXException(message, null);
}
}