如何在Java中保存DOM文档？

问题描述：

我正在使用DOM解析器和XPATH解析我的XML文件。我已更改Document Object中的节点值。但是，当我打开我的XML文件时，它并未向我显示任何反映。我的DOM解析器代码如下：如何在Java中保存DOM文档？

private void setPortNumber(int portNumber) { 
     try { 
     Document parsedDocument = parseDocument(tempPath + "/apache-6/conf/server.xml"); 
     XPath xPath = XPathFactory.newInstance().newXPath(); 
     XPathExpression expr; 
     expr = (XPathExpression) xPath.compile("//Connector"); 
     Object result = expr.evaluate(parsedDocument, XPathConstants.NODESET); 
     NodeList nodes = (NodeList) result; 
     for (int i = 0; i < nodes.getLength(); i++) { 
      Node node =nodes.item(i); 
      NamedNodeMap attributes = node.getAttributes(); 
      for(int j=0; j< attributes.getLength(); j++){ 
       String value = attributes.item(j).getNodeValue(); 
       if(value.equals("HTTP/1.1")){ 
        Node valueNode = attributes.item(0); 
        valueNode.setNodeValue(portNumber+""); 
       } 
      } 
     } 
     } catch (XPathExpressionException e) {} 
    } 
    private Document parseDocument(String xmPath) { 
     Document doc = null; 
     try { 
      DocumentBuilderFactory domFactory = 
       DocumentBuilderFactory.newInstance(); 
      DocumentBuilder builder; 

      builder = domFactory.newDocumentBuilder(); 

      doc = builder.parse(xmPath); 
     }catch (Exception e) {} 
     return doc; 
    }

如何在更改完成后保存文档？

任何人都可以帮助我解决这个问题吗？

答

这里是更新的XML文件

try 
{ 
    DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance(); 
    DocumentBuilder docBuilder = docFactory.newDocumentBuilder(); 
    Document doc = docBuilder.parse(filePath); 
    Node rootNode = doc.getFirstChild();//for getting the root node 

    String expersion="books/author";//x-path experssion 

    XPathFactory factory = XPathFactory.newInstance(); 
    XPath xpath = factory.newXPath(); 
    XPathExpression expr = xpath.compile(expersion); 
    Node updateNode=null; 
    Object result = expr.evaluate(doc, XPathConstants.NODESET); 
    NodeList nodes = (NodeList) result; 
    updateNode=nodes.item(0); 
    updateNode.appendChild(doc.createCDATASection("new value")); 
    TransformerFactory transformerFactory = TransformerFactory.newInstance(); 
    Transformer transformer = transformerFactory.newTransformer(); 
    DOMSource source = new DOMSource(doc); 
    StreamResult streamResult = new StreamResult(new File(filePath)); 
    transformer.transform(source, streamResult); 
} 
catch (Exception e) { 
    e.printStackTrace(); 
}

示例代码

答

您可以使用Transformer API将您的DOM写入流或文件。

答

您必须使用变换器将dom对象转换为XML。

http://download.oracle.com/javaee/1.4/tutorial/doc/JAXPXSLT4.html

如何在Java中保存DOM文档？

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