XML文件解析之JDOM解析

1.JDOM介绍

JDOM的官方网站是http://www.jdom.org/，JDOM解析用到的jar包可以在http://www.jdom.org/dist/binary/中下载，最新的JDOM2的版本是2.0.5，JDOM1的版本是1.1.3，根据官网中的介绍可以知道。JDOM是一个在基于内存的XML模型，它用于读写创建修改XML文档。JDOM和DOM相似因为他们都提供了内存XML文档模型，但是DOM被设计用于很多种语言（C,C++,ECMSctipr,Java,JScript,Lingo,PHP,PLSQL和Python），但是JDOM只是被设计用来处理Java。因为这个原因JDOM不遵循w3c标准规范。JDOM不是一个XML解析器但是它可以使用SAX，STAX或者DOM解析器用来构建一个JDOM文档。

2 JDOM2相关介绍：

2.1.1主要的包包括

org.jdom2

This package contains the core classes that represent the XML components.

Document - Represents the complete XML document. It provides access to the root element and also the docType.
DocType - Represents an XML DOCTYPE.
Element - Represents an XML element. Has methods to manipulate the child elements, its textual content, attributes and namespaces.
Attribute - This represents an XML attribute. There are methods to get and set the value of the attribute and also the namespace. The Attribute has a parent and an AttributeType.
Namespace - Represents an XML Namespace.
CDATA - This represents an XML CDATA section.
Text - This represents an XML Text.
Comment - Represents an XML comment. Users can get and set comment text.
EntityRef - Represents an XML EnityRef.
ProcessingInstruction - Represents an XML Processing Instruction
Content - This is an abstract class which is extended by those classes that can be a child of a org.jdom2.Parent class (Element, CDATA, Comment, DocType, EntityRef, ProcessingInstruction, Text)
org.jdom2.filter

These package has filters that allow filtering based on type, name, value or other parameters. It also allows ANDing, ORing and Negating filters. Filters are used in the public <E extends Content> List<E> getContent(final Filter<E> filter) and public <F extends Content> IteratorIterable<F> getDescendants(final Filter<F> filter) methods of the Element class. Filters are also using in the XPath package of JDom2.

org.jdom2.input

This package has the core classes responsible for building the JDOM2 document from DOM, SAX or StAX. The important classes are

SAXBuilder - Builds a JDOM document from SAX parser.
DOMBuilder - Builds a JDOM document from pre-existing org.w3c.dom.DOM document.
StaxEventBuilder - Builds a JDOM document from StAX XMLEventReader
StaxStreamBuilder - Builds a JDOM document from StAX XMLStreamReader
org.jdom2.output

These package has classes to ouput the JDOM2 document to various destinations. The main classes are :

XMLOutputter - Output a JDOM2 document as a stream of bytes.
DOMOutputter - Convert a JDOM2 document into a DOM document. It can also convert various JDOM2 components to its equivalent DOM components
SAXOutputter - Convert a JDOM2 document into a stream of SAX events
StAXEventOutputter - output a JDOM2 document to an XMLEventWriter.
StAXStreamOutputter - Output a JDOM2 document to an XMLStreamWriter.
Other Packages

org.jdom2.transform - Helps with XML transformation using JAXP TrAX classes.
org.jdom2.xpath - Support for XPath in JDOM2. By default, it uses the Jaxen xpath library

2.1.2具体的实现

http://www.cnblogs.com/hoojo/archive/2011/08/11/2134638.html 这篇文章介绍的很详细，这里不再赘述。感谢@hoojo

3、JDOM1的介绍

废话少说直接写实现：

3.1处理的XML文档内容

<?xml version="1.0" encoding="UTF-8"?>
<world>
    <comuntry id="1">
        <name>China</name>
        <capital>Beijing</capital>
        <population>1234</population>
        <area>960</area>
    </comuntry>
    <comuntry id="2">
        <name id="">America</name>
        <capital>Washington</capital>
        <population>234</population>
        <area>900</area>
    </comuntry>
    <comuntry id="3">
        <name >Japan</name>
        <capital>Tokyo</capital>
        <population>234</population>
        <area>60</area>
    </comuntry>
    <comuntry id="4">
        <name >Russia</name>
        <capital>Moscow</capital>
        <population>34</population>
        <area>1960</area>
    </comuntry>
</world>

3.2具体的实现代码包括读写过程

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.List;

import org.jdom.Attribute;
import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
import org.jdom.output.Format;
import org.jdom.output.XMLOutputter;

public class JDOMParse {


    public static void main(String[] args) {
        // TODO Auto-generated method stub
        parseXML(new File("world.xml"));
        createXML();

    }

    public static void parseXML(File xmlPath){

        SAXBuilder sb = new SAXBuilder();
        try {
            Document doc = sb.build(new FileInputStream(xmlPath));
            Element root = doc.getRootElement();//获得XML的根元素
            System.out.println("根节点:"+root.getName());
            System.out.println("-----------------------------");
            List list = root.getChildren();
            for(int i = 0; i < list.size(); i++){
                Element element = (Element)list.get(i);
                System.out.println("子节点名称:"+element.getName());
                List att_list = element.getAttributes();
                for(int j = 0; j < att_list.size(); j++){
                    Attribute att = (Attribute)att_list.get(j);
                    System.out.println(att.getName()+":"+att.getValue());
                }
                List tempist = element.getChildren();
                for(int t = 0; t < tempist.size(); t++){
                    Element temp  = (Element)tempist.get(t);
                    System.out.println(temp.getName()+":"+temp.getValue());
                }
        
            }
            System.out.println("------------------结束--------------------------");
        } catch (JDOMException e) {
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
    }
    
    public static void createXML(){
        Element root = new Element("root");//创建根元素
        Document doc=new Document(root); 
        Element world = new Element("world");//根元素的子元素
        root.addContent(world);//添加到根
        for(int i=0;i<4;i++){
            Element comuntry = new Element("comuntry");//根元素的子元素
            Attribute att = new Attribute("id",i+"");
            comuntry.setAttribute(att);
            world.addContent(comuntry);
            Element name = new Element("name");//根元素的子元素
            name.setText("中国");
            Element capital = new Element("capital");//根元素的子元素
            capital.setText("Beijing");
            Element population = new Element("population");//根元素的子元素
            name.setText("34");
            Element area = new Element("area");//根元素的子元素
            area.setText("1960");
            
            comuntry.addContent(name).addContent(capital).addContent(population).addContent(area);
        }
        XMLOutputter out = new XMLOutputter();  
        out.setFormat(Format.getCompactFormat().setEncoding("GB2312"));
        System.out.println(out.outputString(doc));
    }
}

3.3.结果

根节点:world
-----------------------------
子节点名称:comuntry
id:1
name:China
capital:Beijing
population:1234
area:960
子节点名称:comuntry
id:2
name:America
capital:Washington
population:234
area:900
子节点名称:comuntry
id:3
name:Japan
capital:Tokyo
population:234
area:60
子节点名称:comuntry
id:4
name:Russia
capital:Moscow
population:34
area:1960
------------------结束--------------------------
<?xml version="1.0" encoding="GB2312"?>
<root><world><comuntry id="0"><name>34</name><capital>Beijing</capital><population /><area>1960</area></comuntry><comuntry id="1"><name>34</name><capital>Beijing</capital><population /><area>1960</area></comuntry><comuntry id="2"><name>34</name><capital>Beijing</capital><population /><area>1960</area></comuntry><comuntry id="3"><name>34</name><capital>Beijing</capital><population /><area>1960</area></comuntry></world></root>

3.4上面的例子是一个很粗糙的举例，需要完善和改进的地方还有很多，比如更加通用化使用递归等等。

4.上面都只是一个简单的总结和记录，很多的不完善的地方，希望大家多多批评指正。

至此XML文件解析的四种方式都已经结束完毕了。