简介：servlet是JavaWeb三大组件之一，是运行在服务器中的小型Java程序，用于接收和响应客户端的请求。一个Servlet的生命周期由实例化、初始化、提供服务、销毁几个步骤组成。
MyServlet01.java
package com.sl.servlet;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* MyServlet01
*/
("/MyServlet01")
public class MyServlet01 extends HttpServlet {
private static final long serialVersionUID = 1L;
public MyServlet01() {
System.out.println("****MyServlet01实例化****");
}
public void init() throws ServletException {
System.out.println("****MyServlet01初始化****");
}
public void destroy() {
System.out.println("****MyServlet01被销毁****");
}
protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
super.service(req, resp);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.getWriter().append("Served at: ").append(request.getContextPath());
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
String account = request.getParameter("account");
String psd = request.getParameter("psd");
if(account.equals("admin") && psd.equals("123456")) {
response.sendRedirect("success.jsp");
System.out.println("账号："+account+"密码:"+psd+"登录成功");
return;
}else {
response.sendRedirect("index.jsp");
System.out.println("账号："+account+"密码:"+psd+"登录失败");
return;
}
}
}index.jsp
<% page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="MyServlet01" method="post">
账号:<input type="text" name="account" />${accountErrorString }<br>
密码:<input type="password" name="psd" />${psdErrorString }<br>
<input type="submit" value="提交" /><br>${errorString }
</form>
</body>
</html>
