java读取XML文件

XML文件 book.xml

<book>
 <person>
  <first>Kiran</first>
  <last>Pai</last>
  <age>22</age>
 </person>
 <person>
  <first>Bill</first>
  <last>Gates</last>
  <age>46</age>
 </person>
 <person>
  <first>Steve</first>
  <last>Jobs</last>
  <age>40</age>
 </person>
</book>

 

程序输出

Root element of the doc is book
Total no of people: 3
First Name: Kiran
Last Name: Pai
Age: 22
First Name: Bill
Last Name: Gates
Age: 46
First Name: Steve
Last Name: Jobs
Age: 40

 

程序代码：

 

import java.io.File;
import org.w3c.dom.Document;
import org.w3c.dom.*;

import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException; 

public class ReadAndPrintXMLFile{

    public static void main (String argv []){
    try {

            DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();
            Document doc = docBuilder.parse (new File("book.xml"));

            // normalize text redivsentation            
            doc.getDocumentElement ().normalize ();
            System.out.println ("Root element of the doc is " + doc.getDocumentElement().getNodeName());


            NodeList listOfPersons = doc.getElementsByTagName("person");
            int totalPersons = listOfPersons.getLength();
            System.out.println("Total no of people : " + totalPersons);

            for(int s=0; s<listOfPersons.getLength() ; s++){


                Node firstPersonNode = listOfPersons.item(s);
                if(firstPersonNode.getNodeType() == Node.ELEMENT_NODE){


                    Element firstPersonElement = (Element)firstPersonNode;

                    //-------                    
                    NodeList firstNameList = firstPersonElement.getElementsByTagName("first");
                    Element firstNameElement = (Element)firstNameList.item(0);

                    NodeList textFNList = firstNameElement.getChildNodes();
                    System.out.println("First Name : " + 
                           ((Node)textFNList.item(0)).getNodeValue().trim());

                    //-------                    
                    NodeList lastNameList = firstPersonElement.getElementsByTagName("last");
                    Element lastNameElement = (Element)lastNameList.item(0);

                    NodeList textLNList = lastNameElement.getChildNodes();
                    System.out.println("Last Name : " + 
                           ((Node)textLNList.item(0)).getNodeValue().trim());

                    //----                    
                    NodeList ageList = firstPersonElement.getElementsByTagName("age");
                    Element ageElement = (Element)ageList.item(0);

                    NodeList textAgeList = ageElement.getChildNodes();
                    System.out.println("Age : " + ((Node)textAgeList.item(0)).getNodeValue().trim());

                    //------

                }//end of if clause

            }//end of for loop with s var

        }
        catch (SAXParseException err) {
               System.out.println ("** Parsing error" + ", line " 
                                          + err.getLineNumber () + ", uri " + err.getSystemId ());
               System.out.println(" " + err.getMessage ());

        }
        catch (SAXException e) {
                Exception x = e.getException ();
                ((x == null) ? e : x).printStackTrace ();

        }
        catch (Throwable t) {
                t.printStackTrace ();
        }
        //System.exit (0);
    }//end of main

}