java - 将 XML 内容保存到 CSV 文件中

Question

我有下面的代码，它包含所有 XML 内容。

现在，我在 beginig 上打开了流编写器，但我不知道如何添加到方法中:

bw.write

ReadXML.java

public class ReadXML {

  public static void main(String[] args) {

    try {

    File file = new File("C:\\test.xml");
    File outputFile = new File("C:\\test.csv");

    DocumentBuilder dBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
    Document doc = dBuilder.parse(file);
    BufferedWriter bw = null;
    FileWriter fw = null;

    System.out.println("Root element :" + doc.getDocumentElement().getNodeName());

    if (doc.hasChildNodes()) {
        printNote(doc.getChildNodes());
    }
    } catch (Exception e) {
    System.out.println(e.getMessage());
    }
  }

  private static void printNote(NodeList nodeList) {

    for (int count = 0; count < nodeList.getLength(); count++) {

    Node tempNode = nodeList.item(count);

    if (tempNode.getNodeType() == Node.ELEMENT_NODE) {

        System.out.println("\nNode Name =" + tempNode.getNodeName() + " [OPEN]");
        System.out.println("Node Value =" + tempNode.getTextContent());

        if (tempNode.hasAttributes()) {

            // get attributes names and values
            NamedNodeMap nodeMap = tempNode.getAttributes();

            for (int i = 0; i < nodeMap.getLength(); i++) {
                Node node = nodeMap.item(i);
                System.out.println("attr name : " + node.getNodeName());
                System.out.println("attr value : " + node.getNodeValue());
            }
        }
        if (tempNode.hasChildNodes()) {
            // loop again if has child nodes
            printNote(tempNode.getChildNodes());
        }
        System.out.println("Node Name =" + tempNode.getNodeName() + " [CLOSE]");
    }    }  }}

你能帮我解决一下吗？如果您知道如何解决该问题，那就太好了。

谢谢!

Answer 1

好吧，仍然不确定您的问题到底是什么，但也许这会有所帮助。

首先，打开编写器:

final BufferedWriter w = new BufferedWriter(new FileWriter(outputFile));

然后将其传递给 printNote:

printNote(doc.getChildNodes(), w);

相应地修改方法:

private static void printNote(final NodeList nodeList, final BufferedWriter w) throws IOException {
    // ...
}

当您拥有要写入文件的节点时，请执行以下操作:

w.write(node.getTextContent());
w.newLine();

完成后不要忘记关闭您的 writer!

编辑

关闭 writer 的示例:

1. 老派

   public static void mainv1(String[] args) {
   
       File file = new File("C:\\test.xml");
       File outputFile = new File("C:\\test.csv");
   
       BufferedWriter bw = null;
   
       try {
           DocumentBuilder dBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
           Document doc = dBuilder.parse(file);
   
           System.out.println("Root element :" + doc.getDocumentElement().getNodeName());
   
           // Open in try because FileWriter constructor throws IOException
           bw = new BufferedWriter(new FileWriter(outputFile));
   
           if (doc.hasChildNodes()) {
               printNote(doc.getChildNodes(), bw);
           }
       } catch (Exception e) {
           System.out.println(e.getMessage());
       } finally {
           // Check for null because bw won't be initialized if document parsing failed
           if (bw != null) {
               try {
                   bw.close();
               } catch (final IOException e) {
                   // Log error
               }
           }
       }
   }
   

2. Java7 及更高版本

   public static void main(String[] args) {
   
       File file = new File("C:\\test.xml");
       File outputFile = new File("C:\\test.csv");
   
       // Since Java7 you can use try-with-resources
       // The finally block closing the writer will be created automatically
       try (BufferedWriter bw = new BufferedWriter(new FileWriter(outputFile))) {
   
           DocumentBuilder dBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
           Document doc = dBuilder.parse(file);
   
           System.out.println("Root element :" + doc.getDocumentElement().getNodeName());
   
           if (doc.hasChildNodes()) {
               printNote(doc.getChildNodes(), bw);
           }
       } catch (Exception e) {
           System.out.println(e.getMessage());
       }
   }