/*
* 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.tomcat.util;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.StringReader;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
/**
* Few simple utils to read DOM
*
* @author Costin Manolache
*/
public class DomUtil {
private static org.apache.juli.logging.Log log=
org.apache.juli.logging.LogFactory.getLog( DomUtil.class );
// -------------------- DOM utils --------------------
/** Get the trimed text content of a node or null if there is no text
*/
public static String getContent(Node n ) {
if( n==null ) return null;
Node n1=DomUtil.getChild(n, Node.TEXT_NODE);
if( n1==null ) return null;
String s1=n1.getNodeValue();
return s1.trim();
}
/** Get the first element child.
* @param parent lookup direct childs
* @param name name of the element. If null return the first element.
*/
public static Node getChild( Node parent, String name ) {
if( parent==null ) return null;
Node first=parent.getFirstChild();
if( first==null ) return null;
for (Node node = first; node != null;
node = node.getNextSibling()) {
//System.out.println("getNode: " + name + " " + node.getNodeName());
if( node.getNodeType()!=Node.ELEMENT_NODE)
continue;
if( name != null &&
name.equals( node.getNodeName() ) ) {
return node;
}
if( name == null ) {
return node;
}
}
return null;
}
public static String getAttribute(Node element, String attName ) {
NamedNodeMap attrs=element.getAttributes();
if( attrs==null ) return null;
Node attN=attrs.getNamedItem(attName);
if( attN==null ) return null;
return attN.getNodeValue();
}
public static void setAttribute(Node node, String attName, String val) {
NamedNodeMap attributes=node.getAttributes();
Node attNode=node.getOwnerDocument().createAttribute(attName);
attNode.setNodeValue( val );
attributes.setNamedItem(attNode);
}
public static void removeAttribute( Node node, String attName ) {
NamedNodeMap attributes=node.getAttributes();
attributes.removeNamedItem(attName);
}
/** Set or replace the text value
*/
public static void setText(Node node, String val) {
Node chld=DomUtil.getChild(node, Node.TEXT_NODE);
if( chld == null ) {
Node textN=node.getOwnerDocument().createTextNode(val);
node.appendChild(textN);
return;
}
// change the value
chld.setNodeValue(val);
}
/** Find the first direct child with a given attribute.
* @param parent
* @param elemName name of the element, or null for any
* @param attName attribute we're looking for
* @param attVal attribute value or null if we just want any
*/
public static Node findChildWithAtt(Node parent, String elemName,
String attName, String attVal) {
Node child=DomUtil.getChild(parent, Node.ELEMENT_NODE);
if( attVal== null ) {
while( child!= null &&
( elemName==null || elemName.equals( child.getNodeName())) &&
DomUtil.getAttribute(child, attName) != null ) {
child=getNext(child, elemName, Node.ELEMENT_NODE );
}
} else {
while( child!= null &&
( elemName==null || elemName.equals( child.getNodeName())) &&
! attVal.equals( DomUtil.getAttribute(child, attName)) ) {
child=getNext(child, elemName, Node.ELEMENT_NODE );
}
}
return child;
}
/** Get the first child's content ( ie it's included TEXT node ).
*/
public static String getChildContent( Node parent, String name ) {
Node first=parent.getFirstChild();
if( first==null ) return null;
for (Node node = first; node != null;
node = node.getNextSibling()) {
//System.out.println("getNode: " + name + " " + node.getNodeName());
if( name.equals( node.getNodeName() ) ) {
return getContent( node );
}
}
return null;
}
/** Get the first direct child with a given type
*/
public static Node getChild( Node parent, int type ) {
Node n=parent.getFirstChild();
while( n!=null && type != n.getNodeType() ) {
n=n.getNextSibling();
}
if( n==null ) return null;
return n;
}
/** Get the next sibling with the same name and type
*/
public static Node getNext( Node current ) {
String name=current.getNodeName();
int type=current.getNodeType();
return getNext( current, name, type);
}
/** Return the next sibling with a given name and type
*/
public static Node getNext( Node current, String name, int type) {
Node first=current.getNextSibling();
if( first==null ) return null;
for (Node node = first; node != null;
node = node.getNextSibling()) {
if( type >= 0 && node.getNodeType() != type ) continue;
//System.out.println("getNode: " + name + " " + node.getNodeName());
if( name==null )
return node;
if( name.equals( node.getNodeName() ) ) {
return node;
}
}
return null;
}
public static class NullResolver implements EntityResolver {
public InputSource resolveEntity (String publicId,
String systemId)
throws SAXException, IOException
{
if( log.isTraceEnabled())
log.trace("ResolveEntity: " + publicId + " " + systemId);
return new InputSource(new StringReader(""));
}
}
public static void setAttributes( Object o, Node parent)
{
NamedNodeMap attrs=parent.getAttributes();
if( attrs==null ) return;
for (int i=0; i<attrs.getLength(); i++ ) {
Node n=attrs.item(i);
String name=n.getNodeName();
String value=n.getNodeValue();
if( log.isTraceEnabled() )
log.trace("Attribute " + parent.getNodeName() + " " +
name + "=" + value);
try {
IntrospectionUtils.setProperty(o, name, value);
} catch( Exception ex ) {
ex.printStackTrace();
}
}
}
/** Read XML as DOM.
*/
public static Document readXml(InputStream is)
throws SAXException, IOException, ParserConfigurationException
{
DocumentBuilderFactory dbf =
DocumentBuilderFactory.newInstance();
dbf.setValidating(false);
dbf.setIgnoringComments(false);
dbf.setIgnoringElementContentWhitespace(true);
//dbf.setCoalescing(true);
//dbf.setExpandEntityReferences(true);
DocumentBuilder db = null;
db = dbf.newDocumentBuilder();
db.setEntityResolver( new NullResolver() );
// db.setErrorHandler( new MyErrorHandler());
Document doc = db.parse(is);
return doc;
}
public static void writeXml( Node n, OutputStream os )
throws TransformerException
{
TransformerFactory tf=TransformerFactory.newInstance();
//identity
Transformer t=tf.newTransformer();
t.setOutputProperty(OutputKeys.INDENT, "yes");
t.transform(new DOMSource( n ), new StreamResult( os ));
}
}