转：XML

public interface XmlDocument {

	public void createXml(String fileName);

	public void parserXml(String fileName);
}

 

 import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintWriter;

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.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.xml.sax.SAXException;
/**
 *  为 XML 文档的已解析版本定义了一组接口。解析器读入整个文档，然后构建一个驻留内存的树结构，
 *  然后代码就可以使用 DOM 接口来操作这个树结构。优点：整个文档树在内存中，便于操作；支持删除、
 *  修改、重新排列等多种功能；缺点：将整个文档调入内存（包括无用的节点），浪费时间和空间；使用场合
 *  一旦解析了文档还需多次访问这些数据；硬件资源充足（内存、CPU）
 */
public class DomDemo implements XmlDocument {
    
    private Document document;
 
    private String fileName;
 
    public void init() {
       try {
           DocumentBuilderFactory factory = DocumentBuilderFactory
                  .newInstance();
           DocumentBuilder builder = factory.newDocumentBuilder();
           this.document = builder.newDocument();
       } catch (ParserConfigurationException e) {
           System.out.println(e.getMessage());
       }
    }
 
    public void createXml(String fileName) {
 
       Element root = this.document.createElement("employees");
       this.document.appendChild(root);
       Element employee = this.document.createElement("employee");
       Element name = this.document.createElement("name");
       name.appendChild(this.document.createTextNode("LUCY"));
       employee.appendChild(name);
       Element sex = this.document.createElement("sex");
       sex.appendChild(this.document.createTextNode("f"));
       employee.appendChild(sex);
       Element age = this.document.createElement("age");
       age.appendChild(this.document.createTextNode("30"));
       employee.appendChild(age);
       root.appendChild(employee);
 
       TransformerFactory tf = TransformerFactory.newInstance();
       try {
           Transformer transformer = tf.newTransformer();
           DOMSource source = new DOMSource(document);
           transformer.setOutputProperty(OutputKeys.ENCODING, "gb2312");
           transformer.setOutputProperty(OutputKeys.INDENT, "yes");
           PrintWriter pw = new PrintWriter(new FileOutputStream(fileName));
           StreamResult result = new StreamResult(pw);
           transformer.transform(source, result);
           System.out.println("create xml file success!");
       } catch (TransformerConfigurationException e) {
 
           System.out.println(e.getMessage());
       } catch (IllegalArgumentException e) {
 
           System.out.println(e.getMessage());
       } catch (FileNotFoundException e) {
 
           System.out.println(e.getMessage());
       } catch (TransformerException e) {
 
           System.out.println(e.getMessage());
       }
 
    }
 
    public void parserXml(String fileName) {
       try {
           DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
           DocumentBuilder db = dbf.newDocumentBuilder();
           Document document = db.parse(fileName);
           NodeList employees = document.getChildNodes();
           for (int i = 0; i < employees.getLength(); i++) {
              Node employee = employees.item(i);
              NodeList employeeInfo = employee.getChildNodes();
              for (int j = 0; j < employeeInfo.getLength(); j++) {
                  Node node = employeeInfo.item(j);
                  NodeList employeeMeta = node.getChildNodes();
                  for (int k = 0; k < employeeMeta.getLength(); k++) {
                     System.out.println(employeeMeta.item(k).getNodeName()
                            + ":" + employeeMeta.item(k).getTextContent());
                  }
              }
           }
           System.out.println("parse finished");
       } catch (FileNotFoundException e) {
           System.out.println(e.getMessage());
       } catch (ParserConfigurationException e) {
           System.out.println(e.getMessage());
       } catch (SAXException e) {
           System.out.println(e.getMessage());
       } catch (IOException e) {
           System.out.println(e.getMessage());
       }
     }
}

 

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.List;
import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
import org.jdom.output.XMLOutputter;
/**
 * 
 * 为减少DOM、SAX的编码量，出现了JDOM；优点：20-80原则，极大减少了代码量。使用场合
 * ：要实现的功能简单，如解析、创建等，但在底层，JDOM还是使用SAX（最常用）、DOM、Xanan文档。
 * 
 */
public class JDomDemo implements XmlDocument {
 
    public void createXml(String fileName) {
      Document document;
      Element  root;
      root=new Element("employees");
      document=new Document(root);
      Element employee=new Element("employee");
      root.addContent(employee);
      Element name=new Element("name");
      name.setText("LUCY");
      employee.addContent(name);
      Element sex=new Element("sex");
      sex.setText("m");
      employee.addContent(sex);
      Element age=new Element("age");
      age.setText("23");
      employee.addContent(age);
      XMLOutputter XMLOut = new XMLOutputter();
      try {
       XMLOut.output(document, new FileOutputStream(fileName));
    } catch (FileNotFoundException e) {
       e.printStackTrace();
    } catch (IOException e) {
       e.printStackTrace();
    }
 
    }
 
    public void parserXml(String fileName) {
       SAXBuilder builder=new SAXBuilder(false); 
       try {
           Document document=builder.build(fileName);
           Element employees=document.getRootElement(); 
           List employeeList=employees.getChildren("employee");
           for(int i=0;i<employeeList.size();i++){
              Element employee=(Element)employeeList.get(i);
              List employeeInfo=employee.getChildren();
              for(int j=0;j<employeeInfo.size();j++){
              System.out.println(((Element)employeeInfo.get(j)).getName()+":"+((Element)employeeInfo.get(j)).getValue());
                  
              }
           }
       } catch (JDOMException e) {
       
           e.printStackTrace();
       } catch (IOException e) {
       
           e.printStackTrace();
       } 
 
    }
}

 

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * 
 * 为解决DOM的问题，出现了SAX。SAX ，事件驱动。当解析器发现元素开始、元素结束、文本、文档的开始
 * 或结束等时，发送事件，程序员编写响应这些事件的代码，保存数据。优点：不用事先调入整个文档，占用
 * 资源少；SAX解析器代码比DOM解析器代码小，适于Applet，下载。缺点：不是持久的；事件过后，若没保存
 * 数据，那么数据就丢了；无状态性；从事件中只能得到文本，但不知该文本属于哪个元素；
 * 使用场合：Applet;只需XML文档的少量内容，很少回头访问；机器内存少；
 */
public class SaxDemo implements XmlDocument {

	public void createXml(String fileName) {
		System.out.println("<<" + fileName + ">>");
	}

	public void parserXml(String fileName) {
		SAXParserFactory saxfac = SAXParserFactory.newInstance();
		try {
			SAXParser saxparser = saxfac.newSAXParser();
			InputStream is = new FileInputStream(fileName);
			saxparser.parse(is, new MySAXHandler());
		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		} catch (SAXException e) {
			e.printStackTrace();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

class MySAXHandler extends DefaultHandler {
	boolean hasAttribute = false;
	Attributes attributes = null;
	public void startDocument() throws SAXException {
		System.out.println("文档开始打印了");
	}
	public void endDocument() throws SAXException {
		System.out.println("文档打印结束了");
	}
	public void startElement(String uri, String localName, String qName,
			Attributes attributes) throws SAXException {
		if (qName.equals("employees")) {
			return;
		}
		if (qName.equals("employee")) {
			System.out.println(qName);
		}
		if (attributes.getLength() > 0) {
			this.attributes = attributes;
			this.hasAttribute = true;
		}
	}

	public void endElement(String uri, String localName, String qName)
	throws SAXException {
		if (hasAttribute && (attributes != null)) {
			for (int i = 0; i < attributes.getLength(); i++) {
				System.out.println(attributes.getQName(0)
						+ attributes.getValue(0));
			}
		}
	}

	public void characters(char[] ch, int start, int length)
	throws SAXException {
		System.out.println(new String(ch, start, length));
	}

}

 

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
import java.util.Iterator;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
/**
 * 
 *  DOM4J 是一个非常非常优秀的Java XML API，具有性能优异、功能强大和极端易用使用的特点，
 *  同时它也是一个开放源代码的软件。如今你可以看到越来越多的 Java 软件都在使用 DOM4J 
 *  来读写 XML，特别值得一提的是连 Sun 的 JAXM 也在用 DOM4J。
 */
public class Dom4jDemo implements XmlDocument {
 
    public void createXml(String fileName) {
       Document document = DocumentHelper.createDocument();
       Element employees=document.addElement("employees");
       Element employee=employees.addElement("employee");
       Element name= employee.addElement("name");
       name.setText("LUCY");
       Element sex=employee.addElement("sex");
       sex.setText("m");
       Element age=employee.addElement("age");
       age.setText("29");
       try {
           Writer fileWriter=new FileWriter(fileName);
           XMLWriter xmlWriter=new XMLWriter(fileWriter);
           xmlWriter.write(document);
           xmlWriter.close();
       } catch (IOException e) {
           System.out.println(e.getMessage());
       }
    }
 
    public void parserXml(String fileName) {
        File inputXml=new File(fileName);
        SAXReader saxReader = new SAXReader();
        try {
           Document document = saxReader.read(inputXml);
           Element employees=document.getRootElement();
           for(Iterator i = employees.elementIterator(); i.hasNext();){
               Element employee = (Element) i.next();
               for(Iterator j = employee.elementIterator(); j.hasNext();){
                   Element node=(Element) j.next();
                   System.out.println(node.getName()+":"+node.getText());
               }
           }
       } catch (DocumentException e) {
           System.out.println(e.getMessage());
       }
     System.out.println("dom4j parserXml");
    }
 
 
}