/*
* 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.nifi.util;
import java.util.ArrayList;
import java.util.List;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class DomUtils {
public static String getChildText(final Element element, final String tagName) {
final Element childElement = getChild(element, tagName);
if (childElement == null) {
return null;
}
final String text = childElement.getTextContent();
return (text == null) ? null : text.trim();
}
public static Element getChild(final Element element, final String tagName) {
final List<Element> children = getChildElementsByTagName(element, tagName);
if (children.isEmpty()) {
return null;
}
if (children.size() > 1) {
return null;
}
return children.get(0);
}
public static List<Element> getChildElementsByTagName(final Element element, final String tagName) {
final List<Element> matches = new ArrayList<>();
final NodeList nodeList = element.getChildNodes();
for (int i = 0; i < nodeList.getLength(); i++) {
final Node node = nodeList.item(i);
if (!(node instanceof Element)) {
continue;
}
final Element child = (Element) nodeList.item(i);
if (child.getNodeName().equals(tagName)) {
matches.add(child);
}
}
return matches;
}
public static NodeList getChildNodesByTagName(final Element element, final String tagName) {
final List<Element> elements = getChildElementsByTagName(element, tagName);
return new NodeList() {
@Override
public Node item(final int index) {
if (index >= elements.size()) {
return null;
}
return elements.get(index);
}
@Override
public int getLength() {
return elements.size();
}
};
}
}