Session保存用戶名到Session域對象中

時間 2019-12-09

原文原文鏈接

Session保存用戶名html

1.構造登陸界面java

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Session保存用戶名</title>
</head>
<body>

<form action="doS3" method= "post">
	用戶名:<input type="text" name="name"/><br/>
	密   碼:<input type="password" name = "pwd"><br/>
	<input type="submit">
</form>

</body>
</html>

　　2.獲取Session並將用戶名保存到Session域對象中ide

package com.oaec.session;

import java.io.IOException;
import java.util.Date;

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

public class servletDemo3 extends HttpServlet {
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		req.setCharacterEncoding("UTF-8");
		resp.setContentType("text/html;charset=UTF-8");
		// req.getAttribute(arg0)
		String name = req.getParameter("name");
		String pwd = req.getParameter("pwd");
		if ("高圓圓".equals(name) && "123".equals(pwd)) {
			// 將用戶名保存在session中
			// 1.得到session
			HttpSession session = req.getSession();
			// 2.將用戶名保存在session中
			session.setAttribute("uname", name);
			resp.sendRedirect("doS4");

		} else {
			resp.sendRedirect("index.html");
		}
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		doGet(req, resp);
	}
}

3.從Session中取出數據並對頁面進行保護沒有登陸經過URL訪問直接重定向到登陸界面即主頁post

package com.oaec.session;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;

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

public class servletDemo4 extends HttpServlet{
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		req.setCharacterEncoding("UTF-8");
		resp.setContentType("text/html;charset=UTF-8");
		//從session中取出數據
		HttpSession session = req.getSession(false);
		Object object = null;
		if (session != null && (object = session.getAttribute("uname"))!=null) {		
				PrintWriter writer = resp.getWriter();
				writer.write("登陸成功<br>");
				writer.write("歡迎你"+object);
			}else {
				//沒有登陸過 直接重定向到主頁
				resp.sendRedirect("index.html");
			}
		}
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		doGet(req, resp);
	}
}