/* * 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.polygene.serialization.javaxxml; import java.util.Optional; import java.util.Spliterator; import java.util.Spliterators; import java.util.function.Consumer; import java.util.stream.Stream; import java.util.stream.StreamSupport; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; /** * javax.xml utilities. */ public class JavaxXml { /** * Find child elements. * * @param parent the parent node * @return a stream of elements */ public static Stream<Element> childElements( Node parent ) { return toStream( parent.getChildNodes() ).filter( JavaxXml::isElement ) .map( JavaxXml::castToElement ); } /** * Find the first child element. * * @param parent the parent node * @return an optional element */ public static Optional<Element> firstChildElement( Node parent ) { return childElements( parent ).findFirst(); } /** * Find child elements named {@literal tagName}. * * @param parent the parent node * @param tagName the tag name * @return a stream of elements named {@literal tagName} */ public static Stream<Element> childElementsNamed( Node parent, String tagName ) { return childElements( parent ).filter( element -> tagName.equals( element.getTagName() ) ); } /** * Find the first child element named {@literal tagName}. * * @param parent the parent node * @param tagName the tag name * @return an optional element named {@literal tagName} */ public static Optional<Element> firstChildElementNamed( Node parent, String tagName ) { return childElementsNamed( parent, tagName ).findFirst(); } /** * Find child nodes holding state. * * @param parent the parent node * @return a stream or child state nodes */ public static Stream<Node> stateChildNodes( Node parent ) { return toStream( parent.getChildNodes() ).filter( JavaxXml::isStateNode ); } /** * Find the first child node holding state. * * @param parent the parent node * @return an optional child state node */ public static Optional<Node> firstStateChildNode( Node parent ) { return stateChildNodes( parent ).findFirst(); } /** * Test if a node holds state. * * Types of nodes holding state: * <ul> * <li>{@link Node#ELEMENT_NODE}</li> * <li>{@link Node#CDATA_SECTION_NODE}</li> * <li>{@link Node#TEXT_NODE}</li> * </ul> * * @param node the node * @return {@literal true} if {@literal node} holds state */ public static boolean isStateNode( Node node ) { switch( node.getNodeType() ) { case Node.ELEMENT_NODE: case Node.CDATA_SECTION_NODE: case Node.TEXT_NODE: return true; default: return false; } } private static boolean isElement( Node node ) { return node.getNodeType() == Node.ELEMENT_NODE; } private static Element castToElement( Node node ) { return (Element) node; } private static Stream<Node> toStream( NodeList nodeList ) { return StreamSupport.stream( new Spliterators.AbstractSpliterator<Node>( Long.MAX_VALUE, Spliterator.ORDERED ) { private int nextIndex = 0; @Override public boolean tryAdvance( Consumer<? super Node> action ) { if( nextIndex >= nodeList.getLength() ) { return false; } action.accept( nodeList.item( nextIndex ) ); nextIndex++; return true; } }, false ); } private JavaxXml() {} }