java中遍历XML节点的问题

Question

我有一个在java中迭代xml的问题。我有一个根节点作为元素，元素标记中有两个子节点，但我得到的节点长度是1。有谁能指导我如何纠正它。我在下面提到了我的代码

import java.io.StringReader;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.CharacterData;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;


public class Test {




        public static void main(String arg[]) throws Exception{


             String xmlRecords = "<data><employee><name>A</name><title>Manager</title><name>B</name><title>Manager</title></employee></data>";

            DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
            InputSource is = new InputSource();
            is.setCharacterStream(new StringReader(xmlRecords));

            Document doc = db.parse(is);

            NodeList nodes = doc.getElementsByTagName("employee");

            for (int i = 0; i < nodes.getLength(); i++) {
              Element element = (Element) nodes.item(i);

              NodeList name = element.getElementsByTagName("name");
              Element line = (Element) name.item(i);
              System.out.println("Name: " + getCharacterDataFromElement(line));

              NodeList title = element.getElementsByTagName("title");
              line = (Element) title.item(i);
              System.out.println("Title: " + getCharacterDataFromElement(line));
            }

          }

          public static String getCharacterDataFromElement(Element e) {
            Node child = e.getFirstChild();
            if (child instanceof CharacterData) {
              CharacterData cd = (CharacterData) child;
              return cd.getData();
            }
            return "";
          }

}

结果：

Name: A
Title: Manager

预期输出：

  Name: A
    Title: Manager
    Name: B
    Title: Manager

Answer 1

两件事：只有一个<employee>节点，所以循环迭代一次。考虑将第二个节点添加到String：

String xmlRecords = "<data><employee><name>A</name><title>Manager</title></employee>" +
                    "<employee><name>B</name><title>Manager</title></employee></data>";

其次，对于<name>和<title>来说，不要在这些内部节点上迭代，因为每个员工内部只有一个节点。所以用零代替i。这当然取决于上述父节点的更改

NodeList name = element.getElementsByTagName("name");
Element line = (Element) name.item(0);

NodeList title = element.getElementsByTagName("title");
line = (Element) title.item(0);

执行以上操作将产生您想要的结果：

Name: A
Title: Manager
Name: B
Title: Manager

Answer 2

您的XML是

<data>
   <employee>
      <name>A</name>
      <title>Manager</title>
      <name>B</name>
      <title>Manager</title>
   </employee>
</data>

我建议你试一下

<data>
   <employee>
      <name>A</name>
      <title>Manager</title>
   </employee>
   <employee>
      <name>B</name>
      <title>Manager</title>
   </employee>
</data>

否则（正确地）只有1个员工节点可以打印其姓名和职务