ServletContext读取Web应用中的资源文件

 package cn.itcast;

 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.PrintWriter;
 import java.util.Properties;

 import javax.servlet.ServletContext;
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 //读取资源文件
 public class ServletDemo1 extends HttpServlet {

     public void doGet(HttpServletRequest request, HttpServletResponse response)
             throws ServletException, IOException {

         test2();
     }

     //通过servletContext的getReadlPath得到资源的绝对路径后，再通过传统流读取资源文件
     public void test2() throws IOException {

         String path = this.getServletContext().getRealPath("/WEB-INF/classes/cn/itcast/db.properties");
         System.out.println(path);
         String filename = path.substring(path.lastIndexOf("\\")+1);
         System.out.println("当前读取到资源名称是："+filename);

         FileInputStream in = new FileInputStream(path);

         Properties props = new Properties();
         props.load(in);

         String url = props.getProperty("url");
         String username = props.getProperty("username");
         String password = props.getProperty("password");

         System.out.println(url+username+password);
     }

     public void test1() throws IOException {
         InputStream in = this.getServletContext().getResourceAsStream("/WEB-INF/classes/cn/itcast/db.properties");

         Properties props = new Properties();
         props.load(in);

         String url = props.getProperty("url");
         String username = props.getProperty("username");
         String password = props.getProperty("password");

         System.out.println(url+username+password);
     }

     public void doPost(HttpServletRequest request, HttpServletResponse response)
             throws ServletException, IOException {

     }

 }

 url=jdbc:mysql://localhost:3306/test
 username=root
 password=root