/*
* 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 java.security.AccessController;
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.tomcat.util.descriptor.DigesterFactory;
import org.apache.tomcat.util.descriptor.LocalResolver;
import org.apache.tomcat.util.descriptor.XmlErrorHandler;
import org.apache.tomcat.util.security.PrivilegedGetTccl;
import org.apache.tomcat.util.security.PrivilegedSetTccl;
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.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
*
*/
public class ParserUtils {
/**
* An entity resolver for use when parsing XML documents.
*/
static EntityResolver entityResolver;
private final EntityResolver entityResolverInstance;
/**
* @deprecated Unused. Will be removed in Tomcat 7.
* Use {@link ParserUtils#ParserUtils(boolean,boolean)} instead.
*/
@Deprecated
public static boolean validating = false;
private final boolean useValidation;
/**
* @deprecated Unused. Will be removed in Tomcat 7.
* Use {@link ParserUtils#ParserUtils(boolean,boolean)} instead.
*/
@Deprecated
public ParserUtils() {
this(true, Constants.IS_SECURITY_ENABLED);
}
public ParserUtils(boolean useValidation, boolean blockExternal) {
this.useValidation = useValidation;
if (entityResolver == null) {
this.entityResolverInstance = new LocalResolver(
DigesterFactory.SERVLET_API_PUBLIC_IDS,
DigesterFactory.SERVLET_API_SYSTEM_IDS, blockExternal);
} else {
this.entityResolverInstance = entityResolver;
}
}
// --------------------------------------------------------- Public Methods
/**
* Parse the specified XML document, and return a <code>TreeNode</code>
* 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
ClassLoader original;
if (Constants.IS_SECURITY_ENABLED) {
PrivilegedGetTccl pa = new PrivilegedGetTccl();
original = AccessController.doPrivileged(pa);
} else {
original = Thread.currentThread().getContextClassLoader();
}
try {
if (Constants.IS_SECURITY_ENABLED) {
PrivilegedSetTccl pa =
new PrivilegedSetTccl(ParserUtils.class.getClassLoader());
AccessController.doPrivileged(pa);
} else {
Thread.currentThread().setContextClassLoader(
ParserUtils.class.getClassLoader());
}
DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
factory.setValidating(useValidation);
if (useValidation) {
// Enable DTD validation
factory.setFeature(
"http://xml.org/sax/features/validation",
true);
// Enable schema validation
factory.setFeature(
"http://apache.org/xml/features/validation/schema",
true);
}
DocumentBuilder builder = factory.newDocumentBuilder();
builder.setEntityResolver(entityResolverInstance);
XmlErrorHandler handler = new XmlErrorHandler();
builder.setErrorHandler(handler);
document = builder.parse(is);
if (!handler.getErrors().isEmpty()) {
// throw the first to indicate there was a error during processing
throw handler.getErrors().iterator().next();
}
} 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);
} finally {
if (Constants.IS_SECURITY_ENABLED) {
PrivilegedSetTccl pa = new PrivilegedSetTccl(original);
AccessController.doPrivileged(pa);
} else {
Thread.currentThread().setContextClassLoader(original);
}
}
// Convert the resulting document to a graph of TreeNodes
return (convert(null, document.getDocumentElement()));
}
/**
* Parse the specified XML document, and return a <code>TreeNode</code>
* 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)));
}
/**
* Set the EntityResolver.
* This is needed when the dtds and Jasper itself are in different
* classloaders (e.g. OSGi environment).
*
* @param er EntityResolver to use.
*/
public static void setEntityResolver(EntityResolver er) {
entityResolver = er;
}
// ------------------------------------------------------ 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);
}
}