XPath解析XML

xpath 介绍

xpath w3c api

项目应用

项目中webservice接口接收xml字符串参数，使用xpath

解析

<!--XML模板--><building>    <sellProject></sellProject> <!--销售项目-->    <number></number> <!--楼栋编码-->    <name></name> <!--楼栋名称-->    <subarea></subarea> <!--所属分区-->    <units><!--单元分录-->        <seq></seq> <!--单元序号-->        <name></name> <!--单元名称-->        <number></number> <!--单元编码-->        <description></description> <!--单元描述-->    </units></building> **注意：XML传输格式中不允许带有“<!---->”注释片段，不然解析后台代码DocumentBuilder 转换为Document时不会报错**

// java使用xpath解析XML后台代码        InputStream is = new ByteArrayInputStream(syncData.getBytes("UTF-8")); // 将字符串转化为字符流        DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();        DocumentBuilder documentBuilder = domFactory.newDocumentBuilder();        Document document = documentBuilder.parse(is);        XPathFactory factory = XPathFactory.newInstance(); // 创建XPathFactory        XPath xPath = factory.newXPath(); // 用这个工厂创建 XPath对象         // 获取building下所有节点        NodeList  nodeList  = (NodeList)xPath.evaluate("building", document, XPathConstants.NODESET);         for(int i =0;i<nodeList.getLength();i++){                Node item = nodeList.item(i);                /*Element element =(Element)item;                NamedNodeMap attributes = item.getAttributes();*/                String sellProject = (String)xPath.evaluate("sellProject", item, XPathConstants.STRING);                checkThis("sellProject",sellProject);// 校验节点值是否为空                String name = (String)xPath.evaluate("name", item, XPathConstants.STRING);                NodeList roomModels = (NodeList)xPath.evaluate("building/roomModels", document, XPathConstants.NODESET);                    for(int j = 0; j<roomModels.getLength();j++){                    Node roomItem = roomModels.item(j);                    String roomName = (String)xPath.evaluate("name", roomItem, XPathConstants.STRING);                    checkThis("roomName",roomName);                    String roomNumber = (String)xPath.evaluate("number", roomItem, XPathConstants.STRING);                    checkThis("roomNumber",roomNumber);                    String roomModelType = (String)xPath.evaluate("roomModelType", roomItem, XPathConstants.STRING);                    checkThis("roomModelType",roomModelType);                }        }