这是一项学术任务,我们获得了一个非常大的XML文件,其中包含数百个这样的条目。对于每个项目,我们应该列出经理的ID,将项目添加到列表的最后一个人的人员ID,以及当前的项目数。我已阅读并重读了Oracle DOM API和各种Node API。我们正在使用JAVA,我不能为我的生活找出如何搜索每个item_list
节点的各个“字段”。以下是我们提供的数据示例。
<item_list id="item_list01">
<numitems_intial>5</numitems_initial>
<item>
<date_added>1/1/2014</date_added>
<added_by person="person01" />
</item>
<item>
<date_added>1/6/2014</date_added>
<added_by person="person05" />
</item>
<numitems_current>7</numitems_current>
<manager person="person48" />
</item_list>
<item_list id="item_list02">
<numitems_intial>5</numitems_initial>
<item>
<date_added>1/15/2014</date_added>
<added_by person="person05" />
</item>
<item>
<date_added>1/1/2014</date_added>
<added_by person="person09" />
</item>
<item>
<date_added>1/9/2014</date_added>
<added_by person="person45" />
</item>
<numitems_current>7</numitems_current>
<manager person="person38" />
</item_list>
我尝试过类似的事情:
NodeList nodes = queryDoc.getElementsByTagName("item_list");
for(int i = 0; i < nodes.getLength(); i++) {
Node node = nodes.item(i);
if(node != null) {
System.out.println(node.manager);
}
}
暂时搞乱这段代码,但我想知道如何从每个节点的各个字段中检索数据。
答案 0 :(得分:10)
如果您正在尝试阅读经理标签的人员属性,您可以按照以下所示进行操作 -
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
public class Test{
public static void main (String[] args)
{
Test test = new Test();
test.readXML();
}
private void readXML()
{
Document doc = null;
try
{
doc = parseXML("/home/abc/Test.xml");
}
catch (ParserConfigurationException e)
{
e.printStackTrace();
}
catch (SAXException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
if(doc != null)
{
NodeList nList = doc.getElementsByTagName("item_list");
for (int i = 0; i < nList.getLength(); i++)
{
Node nNode = nList.item(i);
Element eElement = (Element) nNode;
Element cElement = (Element) eElement.getElementsByTagName("manager").item(0);
System.out.println("Manager ID : " + cElement.getAttribute("person"));
}
}
}
private Document parseXML(String filePath) throws ParserConfigurationException, SAXException, IOException
{
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(filePath);
doc.getDocumentElement().normalize();
return doc;
}
}
答案 1 :(得分:0)
或者,使用xml,您可能需要编辑初始内容。我建议采用以下方法
import java.io.IOException;
import java.io.StringWriter;
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.*;
import org.xml.sax.SAXException;
public class ReadXML {
public static void main(String[] args) {
try {
Document doc = getDocument("/home/abc/Test.xml");
System.out.println(getString(getNodeByName(doc,"item_list01")));
} catch (TransformerException | ParserConfigurationException | IOException | SAXException e) {
// Log e.printStackTrace();
}
}
private static Document getDocument(String filePath) throws ParserConfigurationException, IOException, SAXException {
DocumentBuilderFactory dbfac = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = dbfac.newDocumentBuilder();
return docBuilder.parse(filePath);
}
private static String getString(Node node) throws TransformerException {
StringWriter sw = new StringWriter();
Transformer t = TransformerFactory.newInstance().newTransformer();
t.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
t.setOutputProperty(OutputKeys.INDENT, "yes");
t.transform(new DOMSource(node), new StreamResult(sw));
return sw.toString();
}
public static Node getNodeByName(Document doc, String nodeName) {
Node node = null;
for (int i = 0; i < doc.getDocumentElement().getChildNodes().getLength(); i++) {
if (!getTagName(doc, i).equals("#text")) {
for (int j = 0; j < getNodeName(doc, i).getChildNodes().getLength(); j++) {
if (getNodeName(doc, i, j).equalsIgnoreCase("item_list") && getNodeAttributes(doc,i,j).equalsIgnoreCase(nodeName)) {
node = getNodeName(doc, i);
}
}
}
}
return node;
}
private static String getTagName(Document doc, int i) {
return getNodeName(doc, i).getNodeName();
}
private static Node getNodeName(Document doc, int i) {
return (doc.getDocumentElement().getChildNodes().item(i));
}
private static String getNodeName(Document doc, int i, int j) {
return getNodeName(doc, i).getChildNodes().item(j).getNodeName();
}
private static String getNodeAttributes(Document doc, int i, int j) {
if(getNodeName(doc, i).getChildNodes().item(j).hasAttributes()){
return getNodeName(doc, i).getChildNodes().item(j).getAttributes().item(0).getNodeValue();
}
return "";
}
}