DOM 文档操作和 XML 文件互相转换的 Java 实现代码

转自：http://www.ibm.com/developerworks/cn/xml/x-dmj/code.html

DOM 文档操作和 XML 文件互相转换的 Java 实现代码

=========================================================
Test.java
=========================================================
import javax.xml.parsers.*;
import org.w3c.dom.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.*;
import javax.xml.transform.stream.*;

public class Test{
public static void main(String argv[])
{
Document document;
ManageDomAndXml manageDX = new ManageDomAndXml();
document = manageDX.transformXmlToDom("test.xml");
manageDX.ParseDom(document);
manageDX.AddRecordToDom(document);
manageDX.transformDomToXml(document,"test.xml");
}
}
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ManageDomAndXml.java
============================================================
import java.io.*;
import javax.xml.parsers.*;
import org.w3c.dom.*;
import org.xml.sax.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.*;
import javax.xml.transform.stream.*;

public class ManageDomAndXml{
  static Document document;
  public ManageDomAndXml(){};

//用递归方法遍历DOM树
  public void GetElement(NodeList nodelist){

    Node cnode;
    int i;
    String str;
    int len;

    if(nodelist.getLength() == 0){
return;
    }
    for(i=0;i<nodelist.getLength();i++) {
      cnode = nodelist.item(i);
      if(cnode.getNodeType() == 1) {
        System.out.println(cnode.getNodeName());
        GetElement(cnode.getChildNodes());
      }
      else if(cnode.getNodeType() == 3) {
        str = cnode.getNodeValue();
        len = str.length();
        if(len > 1)
          System.out.println("      "+str+" "+len);
      }
    }
  }

// 遍历所提供的DOM文档.
  public void ParseDom(Document document)
  {
    NodeList nodelist;

    Element element = document.getDocumentElement();
    System.out.println("----"+element.getNodeName());

    nodelist = element.getChildNodes();
    GetElement(nodelist);
  }

// 将提供的XML文件解析成DOM文档
public Document transformXmlToDom(String FileName)
{
   DocumentBuilderFactory factory =
            DocumentBuilderFactory.newInstance();

   try {
   DocumentBuilder builder = factory.newDocumentBuilder();
     document = builder.parse( new File(FileName) );
   } catch (SAXException sxe) {
     Exception  exc = sxe;
     if (sxe.getException() != null)
       exc = sxe.getException();
     exc.printStackTrace();
   }
   catch (ParserConfigurationException pce) {
     System.out.println(pce.getMessage() );
   } catch (IOException ioe) {
     System.out.println(ioe.getMessage() );
   }
   return document;
  }

  // 在指定的文档中增加对象，注意：只是针对所提供的test.xml
  public void AddRecordToDom(Document document)
  {
Element root = document.getDocumentElement();
Element books = document.createElement("COMPUTES");
root.appendChild(books);
Element infor = document.createElement("Title");
books.appendChild(infor);
Text text = document.createTextNode("understand XML");
infor.appendChild(text);
infor = document.createElement("Writer");
books.appendChild(infor);
text = document.createTextNode("IBM");
infor.appendChild(text);
infor = document.createElement("Date");
books.appendChild(infor);
text = document.createTextNode("2001.8.12");
books.appendChild(infor);

  }
   // 将DOM文档转化成指定的XML文件
   public void transformDomToXml(Document document,String FileName)
   {
     try{
      TransformerFactory tFactory = TransformerFactory.newInstance();
      Transformer transformer = tFactory.newTransformer();

      DOMSource source = new DOMSource(document);
      StreamResult result = new StreamResult(new File(FileName));
      transformer.transform(source,result);
     }catch (TransformerConfigurationException tce) {
        System.out.println("   " + tce.getMessage() ); 
     }catch (TransformerException te) {
          System.out.println("   " + te.getMessage() );
     }
  }

}

=====================================================================
test.xml (ansi 格式)
=====================================================================
<?xml version="1.0"?>
<BOOKS>
<COMPUTER>
<Title>C language</Title>
<Writer>Bob Dylan</Writer>
<Date>2000.11.13</Date>
</COMPUTER>
<COMPUTER>
<Title>C++ language</Title>
<Writer>W.Richard</Writer>
<Date>2001</Date>
</COMPUTER>
</BOOKS>