使用JDOM解析xml

首先要导入第三方jar包：  jdom.jar
package my.yaner;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Hashtable;
import java.util.List;
import java.util.Properties;

import org.jdom.Document;
import org.jdom.Element;
import org.jdom.input.SAXBuilder;
import org.jdom.output.XMLOutputter;

public class Utils {

	/**解析一个xml文件, 生成JDOM模型*/
	public static Document loadDOM(InputStream is) throws Exception {
		SAXBuilder sb = new SAXBuilder();
		sb.setValidation(false);
		Document doc = sb.build(is);
		return doc;
	}
	
	/**解析一个xml文件，生成JDOM模型*/
	public static Document loadDOM(File file) throws Exception {
		SAXBuilder sb = new SAXBuilder();
		sb.setValidation(false);
		Document doc = sb.build(file);
		return doc;
	}
	
	/**载入数据1. */
	public void load(File dir) throws Exception {
		//载入配置
		Properties config = new Properties();
		Document configDoc = loadDOM(new File(dir, "config.xml"));
		List list = configDoc.getRootElement().getChildren();
		for(int i = 0; i < list.size(); i++) {
			if(list.get(i) instanceof Element){
				Element elem = (Element) list.get(i);
				String configName = elem.getName();
				String configValue = elem.getTextTrim();
				config.setProperty(configName, configValue);
			}
		}
	}
	
	/**载入数据2. */
	public void loadResourceVersions() throws Exception {
		File baseDir = new File("F:/dbtest");
        Document doc = Utils.loadDOM(new File(baseDir, "fileversion.xml"));
        List list = doc.getRootElement().getChildren("file");
        Hashtable<String, Integer> ret = new Hashtable<String, Integer>();
        for (Object obj : list) {
            Element elem = (Element)obj;
            String fileName = elem.getAttributeValue("path");
            int fileVersion = Integer.parseInt(elem.getAttributeValue("version"));
            ret.put(fileName, fileVersion);
        }
    }
	
	 /** 把一个JDOM模型保存到XML文件中 */
	 public static void saveDOM(Document doc, File file, boolean addSpace) throws Exception{
	        FileOutputStream fos = null;
	        String encoding = System.getProperty("pip_xml_encoding");
	        if (encoding == null) {
	        	encoding = "GBK";
	        }
	        try{
	            XMLOutputter out;
	            if (!addSpace) {
	            	// 删除所有无用的空格
	            	ArrayList stack = new ArrayList();
	            	stack.add(doc.getRootElement());
	            	while (stack.size() > 0) {
	            		Object obj = stack.remove(0);
	            		if (obj instanceof Element) {
	            			Element element = (Element)obj;
	            			List list = element.getMixedContent();
	            			for (int i = 0; i < list.size(); i++) {
	            				Object child = list.get(i);
	            				if (child instanceof String && ((String)child).trim().isEmpty()) {
	            					list.remove(i);
	            					i--;
	            				} else if (child instanceof Element) {
	            					stack.add(child);
	            				}
	            			}
	            		}
	            	}
	            }
	            out = new XMLOutputter("    ", true, encoding);
	            fos = new FileOutputStream(file);
	            BufferedOutputStream bos = new BufferedOutputStream(fos);
	            out.output(doc, bos);
	            bos.flush();
	        }catch(Exception e){
	            throw e;
	        }finally{
	            if(fos != null){
	                try{
	                    fos.close();
	                }catch(IOException e){
	                }
	            }
	        }
	    }

	    /** 把一个JDOM模型保存到XML文件中 */
	    public static void saveDOM(Document doc, OutputStream os) throws Exception{
	        try{
	        	String encoding = System.getProperty("pip_xml_encoding");
	            if (encoding == null) {
	            	encoding = "GBK";
	            }
	            XMLOutputter out = new XMLOutputter("    ", true, encoding);
	            BufferedOutputStream bos = new BufferedOutputStream(os);
	            out.output(doc, bos);
	            bos.flush();
	        } catch(Exception e) {
	            throw e;
	        }
	    }
}