DOM与SAX读取xml文件例程

以如下xml为例

 <books> 

   <book id="001"> 

      <title>Harry Potter</title> 

      <author>afd</author> 

   </book> 

   <book id="002"> 

      <title>Learning XML</title> 

      <author>daf</author> 

   </book> 

 </books> 

Dom4j读取信息源程序

import java.io.File; 

 import java.io.IOException; 

 import javax.xml.parsers.DocumentBuilder; 

 import javax.xml.parsers.DocumentBuilderFactory; 

 import javax.xml.parsers.ParserConfigurationException; 

 import org.w3c.dom.Document; 

 import org.w3c.dom.Element; 

 import org.w3c.dom.Node; 

 import org.w3c.dom.NodeList; 

 import org.xml.sax.SAXException; 



 public class DOMParser { 

   DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance(); 

   //Load and parse XML file into DOM 

   public Document parse(String filePath) { 

      Document document = null; 

      try { 

         //DOM parser instance 

         DocumentBuilder builder = builderFactory.newDocumentBuilder(); 

         //parse an XML file into a DOM tree 

         document = builder.parse(new File(filePath)); 

      } catch (ParserConfigurationException e) { 

         e.printStackTrace();  

      } catch (SAXException e) { 

         e.printStackTrace(); 

      } catch (IOException e) { 

         e.printStackTrace(); 

      } 

      return document; 

   } 

    

   public static void main(String[] args) { 

         DOMParser parser = new DOMParser(); 

         Document document = parser.parse("books.xml"); 

         //get root element 

         Element rootElement = document.getDocumentElement(); 



         //traverse child elements 

         NodeList nodes = rootElement.getChildNodes(); 

         for (int i=0; i < nodes.getLength(); i++) 

         { 

            Node node = nodes.item(i); 

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

               Element child = (Element) node; 

               //process child element 

              System.out.println( child.getAttribute("id"));              

             Node eleTitle = child.getElementsByTagName("title").item(0);

             Node eleAuthor = child.getElementsByTagName("author").item(0);

             String title = eleTitle.getFirstChild().getNodeValue();

             String author = eleAuthor.getFirstChild().getNodeValue();

             System.out.println(title  + "---" + author);

            } 

         }       

   } 

 } 

显示结果

001

Harry Potter---afd

002

Learning XML---daf

 

 

SAX方法例程

 import java.io.IOException;

import java.util.ArrayList;

import java.util.List;



import org.xml.sax.Attributes; 

 import org.xml.sax.SAXException; 

 import org.xml.sax.XMLReader; 

 import org.xml.sax.helpers.DefaultHandler; 

import org.xml.sax.helpers.XMLReaderFactory; 



 public class SAXParser { 



   class BookHandler extends DefaultHandler { 

      private List<String> nameList; 

      private boolean title = false; 

   

      public List<String> getNameList() { 

         return nameList; 

      } 

      // Called at start of an XML document 

      @Override 

      public void startDocument() throws SAXException { 

         System.out.println("Start parsing document..."); 

         nameList = new ArrayList<String>(); 

      } 

      // Called at end of an XML document 

      @Override 

      public void endDocument() throws SAXException {  

         System.out.println("End");  

      } 

      

      /** 

       * Start processing of an element. 

       * @param namespaceURI  Namespace URI 

       * @param localName  The local name, without prefix 

       * @param qName  The qualified name, with prefix 

       * @param atts  The attributes of the element 

       */ 

      @Override 

      public void startElement(String uri, String localName, String qName, 

         Attributes atts) throws SAXException { 

         // Using qualified name because we are not using xmlns prefixes here. 

         if (qName.equals("title")) { 

            title = true; 

         } 

      } 

   

      @Override 

      public void endElement(String namespaceURI, String localName, String qName) 

         throws SAXException { 

         // End of processing current element 

         if (title) { 

            title = false; 

         } 

      } 

               

      @Override 

      public void characters(char[] ch, int start, int length) { 

         // Processing character data inside an element 

         if (title) { 

            String bookTitle = new String(ch, start, length); 

            System.out.println("Book title: " + bookTitle); 

            nameList.add(bookTitle); 

         }

      }             

   } 

    

   public static void main(String[] args) throws SAXException, IOException { 

      XMLReader parser = XMLReaderFactory.createXMLReader(); 

      BookHandler bookHandler = (new SAXParser()).new BookHandler(); 

      parser.setContentHandler(bookHandler); 

      parser.parse("books.xml"); 

      System.out.println(bookHandler.getNameList()); 

   } 

 }