java解析Xml

java中XML格式的字符串4读取方式的简单比较

 

1.java自带的DOM解析. 
import java.io.StringReader;   
import javax.xml.parsers.DocumentBuilder;   
import javax.xml.parsers.DocumentBuilderFactory;   
import org.w3c.dom.Document;   
import org.w3c.dom.Element;   
import org.w3c.dom.Node;   
import org.w3c.dom.NodeList;   
import org.xml.sax.InputSource;   
  
public class ReaderXmlForDOM {   
  
    public static void main(String args[]) {   
          String text ="<XML><A>123</A><B>whl123</B><C>亮亮</C><D>1</D><E>1</E><F>165074</F><G>贫穷</G><H>1698.0</H><I>初级士官</I><J>湖南</J><K>常德</K><L>1</L></XML>"  
            
         long begin = System.currentTimeMillis();   
          parse( text );   
         long after = System.currentTimeMillis();   
          System.out.println("DOM用时"+(after-begin)+"毫秒");   
         }   
       
    public static void parse(String protocolXML) {   
            
        try {   
             DocumentBuilderFactory factory = DocumentBuilderFactory   
                     .newInstance();   
             DocumentBuilder builder = factory.newDocumentBuilder();   
             Document doc = builder   
                     .parse(new InputSource(new StringReader(protocolXML)));   
  
             Element root = doc.getDocumentElement();   
             NodeList books = root.getChildNodes();   
            if (books != null) {   
                for (int i = 0; i < books.getLength(); i++) {   
                     Node book = books.item(i);   
                     System.out.println("节点=" + book.getNodeName() + "\ttext="  
                             + book.getFirstChild().getNodeValue());   
                 }   
             }   
         } catch (Exception e) {   
             e.printStackTrace();   
         }   
     }   
}  
我当时dom解析用时是个不稳定的值在62-78毫秒之间. 
以下的三种方法mian方法里面都是一样的解析那段字符串,记录用时,就不在贴出, 只贴出所用的解析部分 
2.java自带的SAX解析. 
import javax.xml.parsers.SAXParser;   
import javax.xml.parsers.SAXParserFactory;   
import org.xml.sax.InputSource;   
import org.xml.sax.SAXException;   
import org.xml.sax.helpers.DefaultHandler;   
  
public class ReaderXmlForSAX {   
public static void parse(String protocolXML) {   
            
        try {   
             SAXParserFactory saxfac = SAXParserFactory.newInstance();      
             SAXParser saxparser = saxfac.newSAXParser();   
             TestSAX   tsax = new TestSAX();   
             saxparser.parse(new InputSource(new StringReader(protocolXML)),tsax);   
         } catch (Exception e) {   
             e.printStackTrace();   
         }   
     }   
}   
  
class TestSAX extends DefaultHandler{   
       
    private StringBuffer buf;   
    private String str;   
    public TestSAX(){   
         super();   
     }   
        
    public void startDocument() throws SAXException{   
         buf=new StringBuffer();   
         System.out.println("*******开始解析XML*******");   
     }   
       
    public void endDocument() throws SAXException{           
         System.out.println("*******XML解析结束*******");   
     }   
        
    public void endElement(String namespaceURI,String localName,String fullName )throws SAXException{   
         str = buf.toString();   
         System.out.println("节点="+fullName+"\tvalue="+buf+" 长度="+buf.length());   
         System.out.println();   
         buf.delete(0,buf.length());   
       }   
       
    public void characters( char[] chars, int start, int length )throws SAXException{   
        //将元素内容累加到StringBuffer中   
         buf.append(chars,start,length);   
     }   
}  
SAX用时是62毫秒,最快的.但是需要多写一个类 
3.DOM4J解析,需要下载对应的jar包 
import java.util.Iterator;   
import java.util.List;   
import org.dom4j.Document;   
import org.dom4j.DocumentHelper;   
import org.dom4j.Element;   
  
public class ReaderXmlForDOM4J {   
//DOM4j解析XML   
    public static void parse(String protocolXML) {   
           
        try {   
  
             Document doc=(Document)DocumentHelper.parseText(protocolXML);   
             Element books = doc.getRootElement();   
             System.out.println("根节点"+books.getName());   
            // Iterator users_subElements = books.elementIterator("UID");//指定获取那个元素   
             Iterator   Elements = books.elementIterator();   
            while(Elements.hasNext()){   
                Element user = (Element)Elements.next();   
                System.out.println("节点"+user.getName()+"\ttext="+user.getText());   
                List   subElements = user.elements();   
            //    List user_subElements = user.elements("username");指定获取那个元素   
//              System.out.println("size=="+subElements.size());   
//              for( int i=0;i<subElements.size();i++){   
//                  Element ele = (Element)subElements.get(i);   
//                  System.out.print(ele.getName()+" : "+ele.getText()+" ");   
//              }   
                System.out.println();   
            }   
         } catch (Exception e) {   
             e.printStackTrace();   
         }           
     }   
}  
DOM4J的用时为140毫秒,慢 并且还需要单独的jar包 
4.JDOM解析,需要下载对应的jar包 
import java.io.StringReader;   
import java.util.List;   
import org.jdom.Document;   
import org.jdom.Element;   
import org.jdom.input.SAXBuilder;   
import org.xml.sax.InputSource;   
  
public class ReaderXmlForJDOM {   
public static void parse(String protocolXML) {   
         SAXBuilder builder=new SAXBuilder(false);   
        try {   
             Document doc = builder.build(new InputSource(new StringReader(protocolXML)));   
             Element eles = doc.getRootElement(); // 得到根元素   
             System.out.println("根节点"+eles.getName());   
               
             List<Element> list = eles.getChildren(); // 得到元素的集合   
            //List studentList = students.getChildren("student"); // 得到指定元素（节点）的集合   
  
            if( list!=null){   
                for (int i = 0; i < list.size(); i++) {   
                     Element book = (Element)list.get(i);   
                     System.out.println("节点=" + book.getName() + "\ttext="  
                             + book.getValue());   
                 }   
              }   
             } catch (Exception e) {   
             e.printStackTrace();   
         }   
     }   
}  
JDOM的用时为125毫秒,比较慢 并且还需要单独的jar包