如何从xml文档中删除<？xml version ="1.0"encoding ="UTF-8"standalone ="no"？>

Question

我编写了测试代码 - 它创建了简单的XML文档.我的问题是创建的文档包含第一个节点中不需要的数据.有没有办法删除或修改此节点<?xml version="1.0" encoding="UTF-8" standalone="no"?>？

import java.io.ByteArrayOutputStream;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class MyTestClass {

    public static void main(String argv[]) {

      try {
        DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder docBuilder = docFactory.newDocumentBuilder();

        // root elements
        Document doc = docBuilder.newDocument();
        Element rootElement = doc.createElement("company");
        doc.appendChild(rootElement);

        // staff elements
        Element staff = doc.createElement("Staff");
        rootElement.appendChild(staff);

        // firstname elements
        Element firstname = doc.createElement("firstname");
        firstname.appendChild(doc.createTextNode("yong"));
        staff.appendChild(firstname);

        // lastname elements
        Element lastname = doc.createElement("lastname");
        lastname.appendChild(doc.createTextNode("mook kim"));
        staff.appendChild(lastname);

        // nickname elements
        Element nickname = doc.createElement("nickname");
        nickname.appendChild(doc.createTextNode("mkyong"));
        staff.appendChild(nickname);

        // salary elements
        Element salary = doc.createElement("salary");
        salary.appendChild(doc.createTextNode("100000"));
        staff.appendChild(salary);

        Transformer t = TransformerFactory.newInstance().newTransformer();
        ByteArrayOutputStream s = new ByteArrayOutputStream();
        t.setOutputProperty(OutputKeys.INDENT, "yes");
        t.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");
        t.transform(new DOMSource(doc),new StreamResult(s));
        System.out.println(new String(s.toByteArray()));
      } catch (ParserConfigurationException pce) {
        pce.printStackTrace();
      } catch (TransformerException tfe) {
        tfe.printStackTrace();
      }
    }
}

它返回:

 <?xml version="1.0" encoding="UTF-8" standalone="no"?> 
 <company>  
  <Staff>
     <firstname>yong</firstname>
     <lastname>mook kim</lastname>
     <nickname>mkyong</nickname>
     <salary>100000</salary>   
  </Staff> 
 </company>

有没有办法删除或修改此节点<?xml version="1.0" encoding="UTF-8" standalone="no"?>？

Answer 1

您可以将以下内容添加到Transformer中

t.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");

看到这里了解详细信息