org.apache.jasper.xmlparser.ParserUtils Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jasper.xmlparser;
import java.io.IOException;
import java.io.InputStream;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.apache.jasper.Constants;
import org.apache.jasper.JasperException;
import org.apache.jasper.compiler.Localizer;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.w3c.dom.Comment;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
/**
* XML parsing utilities for processing web application deployment
* descriptor and tag library descriptor files. FIXME - make these
* use a separate class loader for the parser to be used.
*
* @author Craig R. McClanahan
* @version $Id: ParserUtils.java 1044162 2010-12-09 23:29:15Z markt $
*/
public class ParserUtils {
/**
* An error handler for use when parsing XML documents.
*/
static ErrorHandler errorHandler = new MyErrorHandler();
/**
* An entity resolver for use when parsing XML documents.
*/
static EntityResolver entityResolver = new MyEntityResolver();
// Turn off for JSP 2.0 until switch over to using xschema.
public static boolean validating = false;
// --------------------------------------------------------- Public Methods
/**
* Parse the specified XML document, and return a TreeNode
* that corresponds to the root node of the document tree.
*
* @param location Location (eg URI) of the XML document being parsed
* @param is Input source containing the deployment descriptor
*
* @exception JasperException if an input/output error occurs
* @exception JasperException if a parsing error occurs
*/
public TreeNode parseXMLDocument(String location, InputSource is)
throws JasperException {
Document document = null;
// Perform an XML parse of this document, via JAXP
try {
DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
factory.setValidating(validating);
DocumentBuilder builder = factory.newDocumentBuilder();
builder.setEntityResolver(entityResolver);
builder.setErrorHandler(errorHandler);
document = builder.parse(is);
} catch (ParserConfigurationException ex) {
throw new JasperException
(Localizer.getMessage("jsp.error.parse.xml", location), ex);
} catch (SAXParseException ex) {
throw new JasperException
(Localizer.getMessage("jsp.error.parse.xml.line",
location,
Integer.toString(ex.getLineNumber()),
Integer.toString(ex.getColumnNumber())),
ex);
} catch (SAXException sx) {
throw new JasperException
(Localizer.getMessage("jsp.error.parse.xml", location), sx);
} catch (IOException io) {
throw new JasperException
(Localizer.getMessage("jsp.error.parse.xml", location), io);
}
// Convert the resulting document to a graph of TreeNodes
return (convert(null, document.getDocumentElement()));
}
/**
* Parse the specified XML document, and return a TreeNode
* that corresponds to the root node of the document tree.
*
* @param uri URI of the XML document being parsed
* @param is Input stream containing the deployment descriptor
*
* @exception JasperException if an input/output error occurs
* @exception JasperException if a parsing error occurs
*/
public TreeNode parseXMLDocument(String uri, InputStream is)
throws JasperException {
return (parseXMLDocument(uri, new InputSource(is)));
}
// ------------------------------------------------------ Protected Methods
/**
* Create and return a TreeNode that corresponds to the specified Node,
* including processing all of the attributes and children nodes.
*
* @param parent The parent TreeNode (if any) for the new TreeNode
* @param node The XML document Node to be converted
*/
protected TreeNode convert(TreeNode parent, Node node) {
// Construct a new TreeNode for this node
TreeNode treeNode = new TreeNode(node.getNodeName(), parent);
// Convert all attributes of this node
NamedNodeMap attributes = node.getAttributes();
if (attributes != null) {
int n = attributes.getLength();
for (int i = 0; i < n; i++) {
Node attribute = attributes.item(i);
treeNode.addAttribute(attribute.getNodeName(),
attribute.getNodeValue());
}
}
// Create and attach all children of this node
NodeList children = node.getChildNodes();
if (children != null) {
int n = children.getLength();
for (int i = 0; i < n; i++) {
Node child = children.item(i);
if (child instanceof Comment)
continue;
if (child instanceof Text) {
String body = ((Text) child).getData();
if (body != null) {
body = body.trim();
if (body.length() > 0)
treeNode.setBody(body);
}
} else {
convert(treeNode, child);
}
}
}
// Return the completed TreeNode graph
return (treeNode);
}
}
// ------------------------------------------------------------ Private Classes
class MyEntityResolver implements EntityResolver {
@Override
public InputSource resolveEntity(String publicId, String systemId)
throws SAXException {
for (int i = 0; i < Constants.CACHED_DTD_PUBLIC_IDS.size(); i++) {
String cachedDtdPublicId = Constants.CACHED_DTD_PUBLIC_IDS.get(i);
if (cachedDtdPublicId.equals(publicId)) {
String resourcePath =
Constants.CACHED_DTD_RESOURCE_PATHS.get(i);
InputStream input = this.getClass().getResourceAsStream(
resourcePath);
if (input == null) {
throw new SAXException(Localizer.getMessage(
"jsp.error.internal.filenotfound", resourcePath));
}
InputSource isrc = new InputSource(input);
return isrc;
}
}
Log log = LogFactory.getLog(MyEntityResolver.class);
if (log.isDebugEnabled())
log.debug("Resolve entity failed" + publicId + " " + systemId);
log.error(Localizer.getMessage("jsp.error.parse.xml.invalidPublicId",
publicId));
return null;
}
}
class MyErrorHandler implements ErrorHandler {
@Override
public void warning(SAXParseException ex) throws SAXException {
Log log = LogFactory.getLog(MyErrorHandler.class);
if (log.isDebugEnabled())
log.debug("ParserUtils: warning ", ex);
// We ignore warnings
}
@Override
public void error(SAXParseException ex) throws SAXException {
throw ex;
}
@Override
public void fatalError(SAXParseException ex) throws SAXException {
throw ex;
}
}