DOM实例之一

 DOM

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 DOMStudentsInfo 
...{

    public static void main(String[] args) 
    ...{
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        System.out.println(dbf.getClass().getName());
        
        try 
        ...{
            DocumentBuilder db=dbf.newDocumentBuilder();
            Document doc=db.parse(new File("students.xml"));
            
            NodeList nl=doc.getElementsByTagName("student");
            int len=nl.getLength();
            for(int i=0;i<len;i++)
            ...{
                Element eltStu=(Element)nl.item(i);
              
                Node eltName=eltStu.getElementsByTagName("name").item(0);
                Node eltAge=eltStu.getElementsByTagName("age").item(0);
            
                String name=eltName.getFirstChild().getNodeValue();
                String age=eltAge.getFirstChild().getNodeValue();
                
                System.out.println("name:"+name);
                System.out.println("age:"+age);
                System.out.println("---------------------");
            }
        } 
        catch (ParserConfigurationException e) 
        ...{
            e.printStackTrace();
        } 
        catch (SAXException e) 
        ...{
            e.printStackTrace();
        } 
        catch (IOException e) 
        ...{
            e.printStackTrace();
        }
    }

}

XML

<?xml version="1.0" encoding="gb2312"?>
<?xml-stylesheet type="text/xsl" href="students.xsl"?>
<students>
  <student sn="01">
     <name>张三</name>
     <age>78</age>
  </student>
  <student sn="02">
     <name>李死</name>
     <age>42</age>
  </student>
</students>

二

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.*;
import org.xml.sax.SAXException;

public class DOMPrinter
...{

    public static void printNodeInfo(Node node)
    ...{
        System.out.println(node.getNodeName()+" : "+node.getNodeValue());
    }
    
    public static void printNode(Node node)
    ...{
        short nodeType=node.getNodeType();
        switch(nodeType)
        ...{
        case Node.PROCESSING_INSTRUCTION_NODE:
            System.out.println("-----------PI start-----------");
            printNodeInfo(node);
            System.out.println("-----------PI end-----------");
            break;
        case Node.ELEMENT_NODE:
            System.out.println("-----------Element start-----------");
            printNodeInfo(node);
            System.out.println("-----------Element end-----------");
            
            NamedNodeMap attrs=node.getAttributes();
            int attrNum=attrs.getLength();
            for(int i=0;i<attrNum;i++)
            ...{
                Node attr=attrs.item(i);
                System.out.println("-----------Attribute start-----------");
                printNodeInfo(attr);
                System.out.println("-----------Attribute end-----------");
            }
            break;
        case Node.TEXT_NODE:
            System.out.println("-----------Text start-----------");
            printNodeInfo(node);
            System.out.println("-----------Text end-----------");
            break;
        default:
            break;
        }
        
        Node child=node.getFirstChild();
        while(child!=null)
        ...{
            printNode(child);
            child=child.getNextSibling();
        }
    }
    
    public static void main(String[] args)
    ...{
        
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        
        try
        ...{
            DocumentBuilder db=dbf.newDocumentBuilder();
            Document doc=db.parse(new File("students.xml"));
            //DOMPrinter domPrinter=new DOMPrinter();
            //domPrinter.printNode(doc);
            
            printNode(doc);
            
        }
        catch (ParserConfigurationException e)
        ...{
            // TODO 自动生成 catch 块
            e.printStackTrace();
        }
        catch (SAXException e)
        ...{
            // TODO 自动生成 catch 块
            e.printStackTrace();
        }
        catch (IOException e)
        ...{
            // TODO 自动生成 catch 块
            e.printStackTrace();
        }

    }


}

XML

<?xml version="1.0" encoding="gb2312"?>
<?xml-stylesheet type="text/xsl" href="students.xsl"?>
<students>
  <student sn="01">
     <name>张三</name>
     <age>78</age>
  </student>
  <student sn="02">
     <name>李死</name>
     <age>42</age>
  </student>
</students>

三

import java.io.File;
import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
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;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.SAXException;

public class DOMConvert
...{

    public static void main(String[] args) 
    ...{
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        try 
        ...{
            DocumentBuilder db=dbf.newDocumentBuilder();
            Document doc=db.parse(new File("students.xml"));
            
            Element eltStu=doc.createElement("student");
            Element eltName=doc.createElement("name");
            Element eltAge=doc.createElement("age");
            
            Text textName=doc.createTextNode("王五");
            Text textAge=doc.createTextNode("18");
            
            eltName.appendChild(textName);
            eltAge.appendChild(textAge);
            
            eltStu.appendChild(eltName);
            eltStu.appendChild(eltAge);
            eltStu.setAttribute("sn","03");
            
            Element root=doc.getDocumentElement();
            root.appendChild(eltStu);
            
            NodeList nl=root.getElementsByTagName("student");
            root.removeChild(nl.item(0));
            
            Element eltStuChg=(Element)nl.item(0);
            Node nodeAgeChg=eltStuChg.getElementsByTagName("age").item(0);
            nodeAgeChg.getFirstChild().setNodeValue("22");
        
            int len=nl.getLength();
            for(int i=0;i<len;i++)
            ...{
                Element elt=(Element)nl.item(i);
                System.out.println("编号：" + elt.getAttribute("sn"));
                
                Node nodeName=elt.getElementsByTagName("name").item(0);
                Node nodeAge=elt.getElementsByTagName("age").item(0);
                
                String name=nodeName.getFirstChild().getNodeValue();
                String age=nodeAge.getFirstChild().getNodeValue();
                
                System.out.println("姓名："+name);
                System.out.println("年龄：" + age);
                
                System.out.println("--------------------");
                
            }
            
            TransformerFactory tff=TransformerFactory.newInstance();
            Transformer tf=tff.newTransformer();
            tf.setOutputProperty("encoding","gb2312");
            DOMSource source=new DOMSource(doc);
            StreamResult result=new StreamResult(new File("convert.xml"));
            tf.transform(source,result);
            
        }
        catch (ParserConfigurationException e) 
        ...{
            e.printStackTrace();
        } 
        catch (SAXException e) 
        ...{
            e.printStackTrace();
        } 
        catch (IOException e) 
        ...{
            e.printStackTrace();
        } 
        catch (TransformerConfigurationException e)
        ...{
            e.printStackTrace();
        }
        catch (TransformerException e) 
        ...{
            e.printStackTrace();
        }
    }

}

XML

<?xml version="1.0" encoding="GB2312"?>
<?xml-stylesheet type="text/xsl" href="students.xsl"?>
<students>
  
  <student sn="02">
     <name>李死</name>
     <age>22</age>
  </student>
<student sn="03"><name>王五</name><age>18</age></student></students>