/*
* 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.jackrabbit.util;
import org.w3c.dom.Attr;
import org.w3c.dom.CharacterData;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/**
* <code>XMLUtil</code>...
*/
public class XMLUtil {
/**
* @param node
* @return true if the given node is of type text or CDATA.
*/
public static boolean isText(Node node) {
int ntype = node.getNodeType();
return ntype == Node.TEXT_NODE || ntype == Node.CDATA_SECTION_NODE;
}
/**
* Concatenates the values of all child nodes of type 'Text' or 'CDATA'/
*
* @param element
* @return String representing the value of all Text and CDATA child nodes or
* <code>null</code> if the length of the resulting String is 0.
* @see #isText(org.w3c.dom.Node)
*/
public static String getText(Element element) {
StringBuilder content = new StringBuilder();
if (element != null) {
NodeList nodes = element.getChildNodes();
for (int i = 0; i < nodes.getLength(); i++) {
Node child = nodes.item(i);
if (isText(child)) {
// cast to super class that contains Text and CData
content.append(((CharacterData) child).getData());
}
}
}
return (content.length()==0) ? null : content.toString();
}
/**
* Same as {@link #getText(Element)} except that 'defaultValue' is returned
* instead of <code>null</code>, if the element does not contain any text.
*
* @param element
* @param defaultValue
* @return the text contained in the specified element or
* <code>defaultValue</code> if the element does not contain any text.
*/
public static String getText(Element element, String defaultValue) {
String txt = getText(element);
return (txt == null) ? defaultValue : txt;
}
/**
* Calls {@link #getText(Element)} on the first child element that matches
* the given local name and namespace.
*
* @param parent
* @param childLocalName
* @param childNamespaceURI
* @return text contained in the first child that matches the given local name
* and namespace or <code>null</code>.
* @see #getText(Element)
*/
public static String getChildText(Element parent, String childLocalName, String childNamespaceURI) {
Element child = getChildElement(parent, childLocalName, childNamespaceURI);
return (child == null) ? null : getText(child);
}
/**
* Returns the first child element that matches the given local name and
* namespace. If no child element is present or no child element matches,
* <code>null</code> is returned.
*
* @param parent
* @param childLocalName
* @param childNamespaceURI
* @return first child element matching the specified names or <code>null</code>.
*/
public static Element getChildElement(Node parent, String childLocalName, String childNamespaceURI) {
if (parent != null) {
NodeList children = parent.getChildNodes();
for (int i = 0; i < children.getLength(); i++) {
Node child = children.item(i);
if (child.getNodeType() == Node.ELEMENT_NODE && childLocalName.equals(child.getLocalName()) && childNamespaceURI.equals(child.getNamespaceURI())) {
return (Element)child;
}
}
}
return null;
}
/**
* Returns the value of the named attribute of the current element.
*
* @param parent
* @param localName attribute local name or 'nodeName' if no namespace is
* specified.
* @param namespaceURI or <code>null</code>
* @return attribute value, or <code>null</code> if not found
*/
public static String getAttribute(Element parent, String localName, String namespaceURI) {
if (parent == null) {
return null;
}
Attr attribute;
if (namespaceURI == null) {
attribute = parent.getAttributeNode(localName);
} else {
attribute = parent.getAttributeNodeNS(namespaceURI, localName);
}
if (attribute != null) {
return attribute.getValue();
} else {
return null;
}
}
}