How to obtain resources in Servlet

package com.test;
import java.io.File;
import java.io.*;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Properties;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class getzy extends HttpServlet {
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
* 
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String path=this.getServletContext().getRealPath("/WEB-INF/classes/mess.properties");
//项目里src的文件都在Tomcat的web-inf/classes的文件夹下
System.out.println(path);
//获取文件的路径
FileInputStream in=new FileInputStream(new File(path));
Properties prop=new Properties();
prop.load(in);
//import java.util.Properties;需要导入这个包
//用load方法加载文件
System.out.println(prop.getProperty("ID"));
System.out.println(prop.getProperty("PASSWORD"));
//通过getProperty（）获取内容
}
}