java使用dom4j解析xml

package com.szkingdom.leejun;

import java.io.InputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

/**
 * 这里是项目中的简易代码目的是为了解析特有格式的xml
 * @author leejun
 *
 */
public class DecodeXML {
	//InputStream strm_xml = new FileInputStream("F:\\stud.xml");
	public static TreeMap<String, String> map = new TreeMap<String,String>();
	public static String MD5_CODE;
	public static void getTreeMap(InputStream strm_xml)
	{
		try {
			SAXReader reader  = new SAXReader();
			reader.setEncoding("GBK");							//设置打开编码
			Document document = reader.read(strm_xml);			//生成document对象
			Element rootElm   = document.getRootElement();		//获取到根节点Message
			
			//迭代取出Message的子节点存入有序的map集合中，并且将md5签名存入成员变量中
			for(Iterator it = rootElm.elementIterator();it.hasNext();){
			      Element subElm  = (Element) it.next();
			      String tmpKey	  = subElm.getName();
			      String tmpValue = subElm.getText();
			      System.out.println("key:"+subElm.getName()+"-----------value:"+subElm.getText());
			      if("sign".equals(tmpKey))
			      {
			    	  MD5_CODE = tmpValue;
			      }
			      else {
			    	  map.put(tmpKey, tmpValue);
			      }
			}
		} catch (DocumentException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	//验签程序
	public static boolean signValid()
	{   
		//生成指定格式的字符串
		if(map.isEmpty()) return false;
		StringBuilder sbMD5 = new StringBuilder();
		Set<String> keys = map.keySet();
		String tmpMD5 = "";
		for(String tmpKey : keys)
		{
			String tmpValue = map.get(tmpKey);
			sbMD5.append(tmpKey+"="+tmpValue+"&");
		}
		sbMD5.deleteCharAt(sbMD5.length()-1);
		System.out.println(sbMD5);
		
		//将字符串加密
		try {
			MessageDigest mdInst = MessageDigest.getInstance("MD5");
			mdInst.update(sbMD5.toString().getBytes());
			tmpMD5 = mdInst.digest().toString();
		} catch (NoSuchAlgorithmException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		System.out.println(tmpMD5);
		if(MD5_CODE.equals(tmpMD5))
		{
			return true;
		}
		else {
			return false;
		}
	}
}