xmlparseutil.java

一个成熟的论坛

package com.singnet.xml;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.Node;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

import com.singnet.data.Constants;


public class XMLParseUtil {
	
	private static XMLParseUtil _instance = null;
	
	
	private Document 			doc;
	private String 				path;
	
	public synchronized static XMLParseUtil getInstance() { 
		if(null == _instance) {
			_instance = new XMLParseUtil();
		}
		
		return _instance;
	}
	
	private XMLParseUtil() {
		System.out.println("I'm Created!");
		this.path = Constants.ROOT_PATH + Constants.CFG_FILE;
		this.doc = getXMLDoc();
		System.out.println("Path : " + this.path);
	}
	
	public String getNodeValue(String nodeName) {
		Node node = getNode(nodeName);
		return node.getText();
	}
	
	public void setNodeValue(String nodeName, String value) {
		Node node = getNode(nodeName);
		node.setText(value);
	}

	
	public void saveNode() {
		try {
			
			OutputFormat format = new OutputFormat("  ", true, "GBK");
			XMLWriter writer = new XMLWriter(new FileWriter(this.path), format);
			writer.write(doc);
			writer.close();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	private Document getXMLDoc() {
		SAXReader reader = new SAXReader();
		Document doc;
		try {
			doc = reader.read(new FileInputStream(this.path));
			return doc;
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (DocumentException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}
	
	private Element getRootElement(Document doc) {
		return doc == null ? null : doc.getRootElement();
	}
	
	private Node getNode(String nodeName) {
		return doc.selectSingleNode("//" + nodeName);
	}

}