ServletContext读取配置文件

package servlet;

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

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

/**
 * Servlet implementation class ServletDemo5
 */
public class ServletDemo5 extends HttpServlet {
    
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        read7();
    }
    private void read7() throws IOException {
        String str = this.getServletContext().getRealPath("/WEB-INF/classes/db.properties");
        System.out.println(str);
        FileInputStream is = new FileInputStream(str);
        Properties prop = new Properties();
        prop.load(is);
        String url = prop.getProperty("url");
        String name = prop.getProperty("username");
        String pwd = prop.getProperty("password");
        System.out.println(url);
        System.out.println(name);
        System.out.println(pwd);
    }
    private void read6() throws IOException {
        FileInputStream is = new FileInputStream("classes/db.properties");
        Properties prop = new Properties();
        prop.load(is);
        String url = prop.getProperty("url");
        String name = prop.getProperty("username");
        String pwd = prop.getProperty("password");
        System.out.println(url);
        System.out.println(name);
        System.out.println(pwd);
    }
    private void read5() throws IOException {
        String str = this.getServletContext().getRealPath("/WEB-INF/classes/db.properties");
        System.out.println(str);
    }
    private void read4() throws IOException {
        InputStream is = this.getServletContext().getResourceAsStream("WEB-INF/classes/servlet/db.properties");
        Properties prop = new Properties();
        prop.load(is);
        String url = prop.getProperty("url");
        String name = prop.getProperty("username");
        String pwd = prop.getProperty("password");
        System.out.println(url);
        System.out.println(name);
        System.out.println(pwd);
    }
    private void read3() throws IOException {
        InputStream is = this.getServletContext().getResourceAsStream("WEB-INF/db.properties");
        Properties prop = new Properties();
        prop.load(is);
        String url = prop.getProperty("url");
        String name = prop.getProperty("username");
        String pwd = prop.getProperty("password");
        System.out.println(url);
        System.out.println(name);
        System.out.println(pwd);
    }

private void read2() throws IOException {
        InputStream is = this.getServletContext().getResourceAsStream("/db.properties");
        Properties prop = new Properties();
        prop.load(is);
        String url = prop.getProperty("url");
        String name = prop.getProperty("username");
        String pwd = prop.getProperty("password");
        System.out.println(url);
        System.out.println(name);
        System.out.println(pwd);
    }

private void read1() throws IOException {
        InputStream is = this.getServletContext().getResourceAsStream("WEB-INF/classes/db.properties");
        Properties prop = new Properties();
        prop.load(is);
        String url = prop.getProperty("url");
        String name = prop.getProperty("username");
        String pwd = prop.getProperty("password");
        System.out.println(url);
        System.out.println(name);
        System.out.println(pwd);
    }

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }

}