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import java.util.ArrayList;
import java.util.Iterator;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
public class Utils {
/**
* Macro to get the content of a unique child element.
*
* @param element The parent element.
* @param tagName The name of the desired child.
* @return The element content or null.
*/
public static String getUniqueChildContent(Element element,
String tagName)
throws Exception
{
return getElementContent(getUniqueChild(element, tagName));
}
/**
* Get the content of the given element.
*
* @param element The element to get the content for.
* @return The content of the element or null.
*/
public static String getElementContent(final Element element)
throws Exception
{
return getElementContent(element, null);
}
/**
* Get the content of the given element.
*
* @param element The element to get the content for.
* @param defaultStr The default to return when there is no content.
* @return The content of the element or the default.
*/
public static String getElementContent(Element element, String defaultStr)
throws Exception
{
if (element == null)
return defaultStr;
NodeList children = element.getChildNodes();
String result = "";
for (int i = 0; i < children.getLength(); i++)
{
if (children.item(i).getNodeType() == Node.TEXT_NODE ||
children.item(i).getNodeType() == Node.CDATA_SECTION_NODE)
{
result += children.item(i).getNodeValue();
}
else if( children.item(i).getNodeType() == Node.COMMENT_NODE )
{
// Ignore comment nodes
}
}
return result.trim();
}
/**
* Gets the child of the specified element having the specified unique
* name. If there are more than one children elements with the same name
* and exception is thrown.
*
* @param element The parent element
* @param tagName The name of the desired child
* @return The named child.
*
* @throws Exception Child was not found or was not unique.
*/
public static Element getUniqueChild(Element element, String tagName)
throws Exception
{
Iterator<Element> goodChildren = getChildrenByTagName(element, tagName);
if (goodChildren != null && goodChildren.hasNext()) {
Element child = goodChildren.next();
if (goodChildren.hasNext()) {
throw new Exception
("expected only one " + tagName + " tag");
}
return child;
} else {
throw new Exception
("expected one " + tagName + " tag");
}
}
/**
* Returns an iterator over the children of the given element with
* the given tag name.
*
* @param element The parent element
* @param tagName The name of the desired child
* @return An interator of children or null if element is null.
*/
public static Iterator<Element> getChildrenByTagName(Element element,
String tagName)
{
if (element == null) return null;
// getElementsByTagName gives the corresponding elements in the whole
// descendance. We want only children
NodeList children = element.getChildNodes();
ArrayList<Element> goodChildren = new ArrayList<Element>();
for (int i=0; i<children.getLength(); i++) {
Node currentChild = children.item(i);
if (currentChild.getNodeType() == Node.ELEMENT_NODE &&
((Element)currentChild).getTagName().equals(tagName)) {
goodChildren.add((Element)currentChild);
}
}
return goodChildren.iterator();
}
}
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