1.JSP内置对象
请求对象：request
输出对象：out
响应对象：response
应用程序对象：application
会话对象：session
页面上下文对象：pageContext
页面对象：page
配置对象：config
异常对象：exception
2.request对象的常用方法：
String getParameter(String name)：根据页面表单组件名称获取页面提交数据
String [ ] getParamterValues(String name):获取一组以相同 名称命名的表单组件 提交的数据
void setCharacterEncoding(String charset): 指定每个请求的编码，在调用request.getParameter()方法之前进行设定，可以用于解决中文乱码问题
RequestDispatcher getRequestDispatcher(String payh):返回一个javax.servlet.RequestDispacher对象，该对象的foeward()
index：
<%@ page language="java" contentType="text/html; charset=UTF-8" ???pageEncoding="UTF-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body> ???<% ???????String username = request.getParameter("username"); ???????String password = request.getParameter("password"); ???????if (username.equals("lps") && password.equals("lucky")) { ???????????response.sendRedirect("welcome.jsp"); ???????} else { ???????????out.println("请检查用户名和密码是否正确！"); ???????} ???%></body></html>controller：
<%@ page language="java" contentType="text/html; charset=UTF-8" ???pageEncoding="UTF-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body> ???<form action="controller.jsp" method="post"> ???????<table> ???????????<tr> ???????????????<td>用户名</td> ???????????????<td><input type="text" name="username"></td> ???????????</tr> ???????????<tr> ???????????????<td>密码</td> ???????????????<td><input type="password" name="password"></td> ???????????</tr> ???????????<tr> ???????????????<td colspan="2"><input type="submit" value="登录"></td> ???????????</tr> ???????</table> ???</form></body></html>
welcome：
<%@ page language="java" contentType="text/html; charset=UTF-8" ???pageEncoding="UTF-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body> ???<h1>欢迎您，来到贵美！</h1></body></html>
方法用于转发请求
JSP数据交互(一)
原文地址：https://www.cnblogs.com/864466244qq/p/8946708.html